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Women-run Cereal Bank in Niger Combats Food Crisis

Women-run Cereal Bank in Niger Combats Food Crisis

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June 9, 2014

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Food Tank

A number of soudure banks run exclusively by women in Niger are combating hunger and promoting agricultural recovery by allowing farming families to stay together and focus on cultivating their own land.


Chapter 5 - Promotion of food and dietary diversification strategies to enhance and sustain household food security

Many people lack adequate amounts of foods that are rich in the nutrients needed for health and a productive life. Chronic undernutrition affects some 215 million people in sub-Saharan Africa, or 43 percent of the population (FAO, 1996b). Deficiencies of iron, vitamin A and iodine are also widespread about 300 million people are affected every year, and a much greater number are at risk of these deficiencies. Malnutrition increases people's vulnerability to infections, causing numerous deaths (see also Chapter 8). In the face of this bleak situation, major efforts are required by national governments and the international community to bring about reductions in malnutrition and micronutrient deficiencies.

Food diversification for stable access and a sustainable food supply

Increased food production and access are crucial to achieving major nutritional improvement. More foods should be produced that are rich in all the essential micronutrients, available in sufficient quantities and accessible to people all year round. This requires the collaboration of people working in agriculture, fishery, forestry, small animal husbandry, industry, marketing, communications, women's participation, home economics and nutrition. The wide application of proven technologies and approaches in these fields, as well as the development of new concepts, will contribute towards solving nutritional problems. The results of research must be transmitted to farmers, and efforts must be made to build on farmers' indigenous knowledge. Consumers, too, need to be involved and educated on how to prevent nutritional deficiencies.

Access to stable and sustainable food supplies is a precondition for the establishment of food security at the household level. Greater and more sustained yields from the farming system will increase the potential access of the household to an adequate diet. Similarly, farming practices that improve the regular flow of a variety of different foods into the household throughout the seasons enhance food security for its members. Promoting appropriate and improved technologies for home preservation and drying of vegetables and fruits at home will reduce wastage and ensure better utilization of fresh produce (e.g. mangoes) available in abundance during the harvest season. Increased food processing through the establishment and strengthening of small-scale agro-industries can contribute to the year-round availability and variety of micronutrient-rich foods in rural and urban markets. Agro-processing industries will not only even out seasonal price fluctuations, but will also create jobs and incomes from such activities as processing, storage, distribution and marketing. Agro-processing will also stimulate demand for farmers' crops and products and give consumers additional choice.

Strategies for food and dietary diversification at the community and household levels include a range of food-based activities that can maximize the availability of adequate amounts and greater variety of nutritious foods. These activities include:

· promotion of mixed cropping and integrated farming systems

· introduction of new crops (such as soybean)

· promotion of underexploited traditional foods and home gardens

· promotion of fishery and forestry products for household consumption

· promotion of improved preservation and storage of fruits and vegetables to reduce waste, post-harvest losses and effects of seasonality

· strengthening of small-scale agro-processing and food industries

· nutrition education to encourage the consumption of a healthy and nutritious diet year round.

Some of these strategies are discussed in this chapter. Diversification must entail management and generation of resources in such a way that all the various measures undertaken collectively work to improve the livelihood of the rural poor.

Mixed cropping

Traditional farming systems already use a diversity of crops in both mixed and relay intercropping as well as integration of crops with livestock and/or aquaculture. Research on cropping patterns and rotations is generating improved methods to ensure greater and more sustained yields. A holistic approach to research on farming systems, combining knowledge of socio-economic constraints and a better understanding of small farmers' conditions, should help in finding solutions.

For small-scale producers, mixed cropping can be associated with potential yield improvements and monetary advantages as well as positive implications for food security, dietary balance and nutrition. Mixed cropping reduces the risk of crop failure. It can also reduce the need for expensive inputs if crop residues from leguminous intercrops, supplemented where appropriate with rock phosphate, are returned to the soil. Mixed and/or rotational cropping offers increased protection from disease and pest damage, thus potentially increasing profitability and income. All of these attributes reduce risk in the food supply system and thus favourably influence food security.

Farming systems based on mixed cropping can extend the harvesting period and help to alleviate seasonal food shortages, thus enhancing the stability of household food access. They can also reduce erosion risks by providing increased soil cover and additional crop residues for use as green manure and mulch. Such characteristics offer gains in sustainability and in stability for the food supply system.

The choice of intercrops usually includes legumes and/or oilseeds such as melon seed, groundnut, soybean or sunflower, together with cereals as the dominant crop. In terms of dietary balance, grain legumes, or pulses, contain more protein than cereals and about ten times as much protein as most roots and tubers (Table 22). More significantly, in composition the proteins in cereals and legumes are complementary to each other.

Proteins are not all equally effective in promoting growth. The quality of a protein is determined by the kind of amino acids it contains and the proportion in which they are present. Good-quality proteins contain all the essential amino acids in proportions capable of promoting growth when they are the only proteins in the diet. Such proteins are known as complete proteins or proteins of high biological value. All animal proteins are complete proteins, and if eaten in adequate amounts they meet all a person's protein needs. Proteins from vegetable sources, such as beans, contain all the essential amino acids, but contain one or more of them in insufficient quantity to meet the needs for growth. Bean proteins are generally rich in lysine, an amino acid often deficient in cereal proteins, and legume proteins are therefore valuable supplements to cereal-based diets. Table 23 shows the amino acid composition and amino acid score of wheat and chickpea (Cicer arietinum), separately and in combination. An optimal protein quality can be obtained by combining wheat and chickpea at a ratio of approximately 2:1.

Table 22 - Comparative energy and protein content of some cereals, tubers, legumes and oilseeds (per 100 g)

Source: FAO/United States Department of Health. Education and Welfare, 1968.

The total protein content of different legumes varies widely, from around 12 percent for some varieties of chickpea to over 35 percent for high-protein cultivars of winged bean (Psophocarpus tetragonolobus) and soybean (Glycine max) (Table 24). Protein content also varies widely among different varieties of the same species. For example, the protein content of pigeon pea (Cajanus cajan) can vary from 13 to 20 percent, depending on the cultivar and the conditions of cultivation.

Table 23 - Essential amino acid content of wheat and chickpea (Cicer arietinum) (mg per g nitrogen in the food)

Source: Siegel and Fawcett, 1976 (quoted in FAO, 1989f).

a Amino acid score = amino acid content in wheat/chickpea mixture - amino acid content in ideal protein (egg) x 100.

Table 24 - Proximate composition of mature, dry winged bean seeds, compared with some commercial dry legume seeds (%)

Source: Vietmeyer, 1975 (quoted in FAO, 1989f).

The diversity of food supplies offered by mixed cropping systems accords well with nutritional security, especially since the young leaves of many grain legumes, such as cowpea, are also utilized as a green vegetable, providing essential minerals such as calcium and iron together with useful amounts of vitamins A and C. Table 25 lists some specific nutrients found in the major plant groups.

Improving mixed cropping technologies through farming systems studies and adaptive research

Farming systems research can contribute to the nutritional wellbeing and food security of households in a number of ways. With its comprehensive, interdisciplinary nature and its aim to improve the viability of small farms, such research is geared towards promoting sustainable livelihoods. It also includes a priority focus on increasing household food production and improving the assets of the farm household.

Farming systems research is directed towards improving the access of farm households to food and income through interventions related to choice of crops and cropping practices, increased use of small livestock, development of labour-saving technologies and improved storage and processing techniques. Thus strategies to encourage food diversification, such as promotion of mixed cropping technologies (including systems integrating crops with livestock and/or aquaculture), should include support for farming systems research and for the efforts of adaptive research planning teams which work directly with farmers in developing locally appropriate systems of integrated farming. Specific emphasis should be given in farming systems research to increasing the micronutrient output of agricultural systems and developing effective storage and preservation techniques for fruits and vegetables that can be employed at the household and community levels.

Table 25 - Specific nutrients found in the major plant groups

Carbohydrates, protein, dietary fibre, a vitamin B complex, a iron, a calcium a

Carbohydrates, protein, some vitamin C

Carbohydrates, protein, dietary fibre, a iron, a calcium, a vitamin B complex a

Vitamin C, vitamin A, iron, calcium, vitamin B complex, dietary fibre

Note: The diets of vulnerable groups may be low in ail these nutrients.

a Particularly high nutrient values are found in the hull.

Support services and advocacy for mixed cropping

Improved agricultural practices for a wider variety of food crops, once disseminated and accepted by the producers, often need support if they are to be widely adopted. For the integration of nutrition objectives into farming systems research, such support may be needed at the policy level. Actors involved in providing support may include government agencies through extension services, together with financial institutions, agricultural banks, farmer groups, fertilizer and seed companies, food industries and other private-sector agencies who may wish to profit from policies for food diversification.

The aim must be to provide timely and appropriate inputs, advice and assistance to farmers and producers to maximize the returns and minimize the risks arising from adoption of new strategies. Development of improved seed, together with advice on cultural practices and required inputs, must generally be accompanied by increased access to low-interest credit and greater security of land tenure to reduce risks in marginal areas. Action will also be required to ensure effective demand and marketing.

Smallholder farmers are profit maximizers and will adopt improved technologies if they are not too risky and are profitable at an early stage in the adoption process. Risk is perceived not only in terms of monetary returns, but also in terms of the stability and sustainability of the household's livelihood, including access to food.

The adoption of strategies to improve the productivity of mixed farming systems, if successful, will create an increased supply of a variety of foods in excess of the immediate demand for food within the producer communities. Therefore, before a food diversification strategy is undertaken, it will be necessary to assess and ensure marketability of excess products. Consumer surveys regarding the promoted crops will be required, together with advocacy and nutrition education to stimulate demand among urban groups, who may have become unfamiliar with some traditional foodstuffs.

The United Nations University Institute for Natural Resources in Africa (UNU/INRA) has commissioned a series of studies in 14 African countries on indigenous food crops and other useful plants, to determine people's knowledge of indigenous crops, the use they make of them and the preparations that are made from them. The aim of the surveys is to provide data for determining the status of, and priorities and strategies for, research and training related to indigenous food crops. Such information would be useful in improving cropping systems utilizing indigenous food crops in planning to enhance sustainability, to reduce risks of crop failure, to diversify production to meet farmers' food needs and to ensure genetic conservation of indigenous African food crops and in promoting improved methods of cultivation, processing and preparation.

In the case of small-grained cereals such as millets and sorghum, improved processing techniques may be necessary to provide products for urban housewives, who have become used to the convenience of rice and of wheat-based baked products such as breads and biscuits. Development of appropriate snack foods based on a wide variety of crops will help provide a market to absorb anticipated surpluses. In addition, widespread dissemination of nutritional information about these products should accompany their marketing.

Many of the foodstuffs produced in diversified farming systems, such as roots and tubers, plantains and bananas, and fruits and leafy vegetables, are highly perishable. As their production is promoted, therefore, transport and marketing facilities need to be enhanced to avoid post-harvest losses, whose high cost is inevitably passed on to the consumer. Agricultural policies favouring diversification should ideally entail a review of all sectors of the food chain from production to consumption, as well as mobilization of support at the national, district and community levels through producer and consumer interest groups.

Gardening for food

In many agricultural communities, people rely on one main staple crop whose seasonality implies a period of food shortage, usually referred to as the lean or the hungry season. Home gardening can often supplement family food supplies during lean periods and can generate added income when other sources of employment and income may be limited, provided enough water is available. Home gardens have mostly been maintained by women, who often water and manure them from domestic wastes and use them to produce early crops such as green maize and the fruits, spices and vegetables needed to prepare relishes.

Home gardens are labour intensive, but as they are usually close to the house, the labour required can be combined with home and child care responsibilities. Children are often responsible for carrying water and for simple maintenance work, and they may also be given a few plants or a small area to tend. Support of home gardening through horticultural training and nutrition education at school, including the establishment and maintenance of a school food production garden, will provide useful training in intensive land management for the next generation.

Home gardening is quickly taking different forms to suit individual lifestyles and work patterns. For example, urban dwellers grow maize in the backyard and quite often in the front garden as well busy traders plant bananas behind their roadside stalls and scatter tomato seeds in damp areas around their compound living area and children bury mango seeds in rubbish heaps and in drains at the side of their houses. Gardening is often rather haphazard and disorganized at this level, with chickens and goats competing for the harvest, but the intention and interest in home gardening are there, waiting to be harnessed.

Unfortunately, home gardens have rarely received official recognition, and families often lack the necessary resources, knowledge and inputs to produce crops as effectively as possible. A survey in Ghana indicated that traditional home garden farming systems have a number of major constraints which need to be removed if the systems are to be successfully promoted (Asare, Oppong and Twum-Ampofo, 1985). Important factors to consider in encouraging the expansion of home gardens include security of land tenure to facilitate long-term investment in home gardens and better extension services, including credit, to promote the wider establishment of home gardens and improve their management.

Home gardens and nutrition

Traditional home gardens continue to be important sources of micronutrients for rural communities. Poor people obtain most of their nutrients from food plants, which are cheaper and more accessible than animal foods. In humid tropical countries, green leafy plants such as Amaranthus s pp., Corchorus spp., Bidens pilosa, Gynandropsis spp., Celosia spp., Basella spp., Solanum scabrum, Solanum americanum, Hibiscus sabdariffa and Vigna unguiculata often grow wild and spontaneously. Traditionally, they have been consumed as leafy vegetables when climatic conditions have made the cultivation of exotic vegetables more difficult. The leaves of these plants tend to be good sources of protein, phosphorus and iron as well as vitamins A and C and in some cases B-group vitamins. In many cases they are of higher overall food value than introduced vegetable species, for example cabbage or tomatoes. Table 26 shows the nutritional content of some green leafy vegetables widely used in Africa.

Through careful selection, a range of fruit and vegetable crops can be cultivated throughout the year to provide a constant supply of micronutrients (see Figure 19). For example, yellow and orange perennial fruits (e.g. mango, papaya, cape gooseberry and guava), fruit vegetables (e.g. tomato, pumpkin, squash, gourd and eggplant), some root vegetables (e.g. carrot and yellow-fleshed sweet potato) and most dark-green leafy vegetables are generally moderate to good sources of vitamins A and C. Also, some leaves and fruits produced by local indigenous trees are consumed in rural areas and are rich in micronutrients, e.g. guavas and loquats. Some sources of nutrition from the home garden are given in Table 27.

Some staple foods also have a role as sources of micronutrients. For instance, leaves of roots and tubers are valuable sources. In many countries of the African humid tropics, leaves of cassava (Manihot esculenta) are also consumed. Millets are rich sources of iron in comparison with other cereals such as wheat or maize.

Fruit and vegetable cultivation presents rather different challenges under low-temperature conditions such as those found in the remote highlands of Ethiopia or Lesotho. In such areas, efforts to extend the production of leafy vegetables into the winter season, for example, need to be based on the selection of cold-tolerant cultivars of Brassica crops such as kale and mustard. Alternatively, it might be advisable to adopt locally appropriate protected cultivation practices, such as the use of simple low plastic tunnels or hotbeds which accumulate solar heat and shield crop plants from exposure to extremely low temperature and wind.

Table 26 - Nutritional content of some green leafy vegetables (per 100 g edible portion)

Baobab leaves (Adansonia digitata)

Bitter feat (Vernonia amygdalina)

Cassava leaf (Manihot esculenta)

Cat's whiskers (Cleome gynandra)

Sweet potato (Ipomoea batatas)

Leaves, cooked, plus groundnuts

FIGURE 19 - Food availability from home food production and supply systems, Nchelenge, Zambia

Source: Adapted from Thuvesson, 1988.

Table 27 - Some sources of nutrition from the home garden

Source: Adapted from WHO/UNICEF, 1985.

For fruit and vegetable crops, staggering planting dates in the case of short-cycle crops and choosing a mixture of early maturing, average and late-maturing varieties for both annual and perennial crops can extend the harvest period. For instance, some varieties of mango tree can be harvested three times a year, with flowering, first budding, ripening and harvesting stages occurring simultaneously on different parts of the same tree. Thus the problem of seasonality of available nutrients, in this case primarily beta-carotene, can be overcome.

Role of women in home gardening

The role of women in home and community gardens is of special importance. In addition to being responsible for producing crops on small plots of land, women, especially those who are elderly, often have good knowledge of indigenous species of green leafy vegetables they know how to prepare them and how to preserve both seeds and produce. In local markets, the main vendors of these crops (fresh or dried) are often women.

Extension services unfortunately tend to focus on the major field crops. Improved planting materials, better cultivars and advice on cultural practices are rarely offered to cultivators of home gardens. Since women do the bulk of the work and are more conscious of and concerned with the nutritional needs of the family, extension advice, credit and agricultural inputs should be provided to them for maximum benefits. The organization of women's groups should be promoted to facilitate their access to inputs, to improve the efficiency of their work and thus to improve the diversity and productivity of gardens.

Home gardening as a development strategy

It is important to distinguish between traditional gardens, which are cultivated independently of any intervention, and promoted gardens, which receive external assistance. Many gardening projects, especially those that promote home gardening for nutritional and income-generating benefits, are supported by external donors and non-governmental organizations (NGOs). The involvement of ministries of agriculture has generally been limited, as horticulture is still given a low priority in overall agricultural development programmes, and home gardening, in spite of its potential output, receives even less attention. Consequently, few agricultural extensionists have been trained in gardening techniques, and even fewer in mixed tropical gardening. Still fewer have the knowledge to promote better diets and nutritional practices.

The neglect of gardening in development strategies is partly explained by the paucity of data on the output of traditional home gardening systems expressed in quantitative and monetary-equivalent terms which could demonstrate a significant contribution to economic output and national development. As a result, most agricultural and research programmes tend to underestimate or discount the actual or potential importance of home gardening as a food security strategy, and in particular as a strategy for meeting micronutrient needs.

However, as more evidence showing the social, economic and nutritional benefits of home gardening is becoming available, some governments and the private sector are showing renewed interest in gardening activities. Case-studies from Bangladesh and Central America that examined the socio-economic aspects of home gardening and its contribution to family consumption and income provide strong evidence that home gardening has significant economic benefits and that it can be a viable strategy for increasing food supplies for family consumption (Marsh, 1994).

In an integrated nutrition/home gardening programme supported by Helen Keller International in Bangladesh, overall vegetable consumption increased by 30 percent, with home gardens supplying 80 percent of vegetables consumed by the family. As most of the income earned from sale of home garden produce was spent on food, the prevalence of malnutrition among children of participating families was also reduced. In a study in Honduras and Nicaragua, the gardens supplied a significant proportion of fruits and vegetables, legumes, roots and tubers, coffee, tea and medicinal plants for home consumption. The combined benefits of home consumption, income earned from sale of garden produce (25 percent of total average income in Bangladesh, although wide variation was recorded in Honduras and Nicaragua) and savings in expenditure on garden produce were judged to make a significant contribution to the household economy.

Data from an FAO-supported project in the Niger promoting the production and consumption of vitamin A-rich foods among women's groups and their families showed that the proportion of healthy children increased in the project areas, in comparison with the non-project villages (IVACG, 1994). The successful ingredients of this project were: a strong emphasis on nutrition education to promote underutilized indigenous foods such as green leaves the cultivation of traditional wild sources of vitamin A and the use of food preservation and solar drying to address the problem of seasonal shortages.

Available evidence clearly suggests that home gardening can result in tangible benefits for the household, including food on the table, extra income and healthy children. Access to home-grown fruits, vegetables, small animals and/or fish ensures a more balanced diet for rural families with limited purchasing power and increases their self-reliance. The sale of surpluses can provide direct benefits to producers, especially women farmers, and can also benefit consumers by increasing the quantity and diversity of food supplies in local markets. In communities where specific nutritional deficiencies persist or where there appear to be unexploited possibilities for income generation, households can with some support from government services or NGOs improve the diversity and productivity of their traditional gardens. Home gardening can also be a potentially important element in urban food security strategies.

For home garden projects to be successful and sustainable, a number of important elements need to be considered. Since home gardening is a complex and varied production system forming part of a wider household economy, garden interventions to improve nutrition require a good understanding of local conditions so that project goals can be adapted locally. Thus it is necessary to work closely with local farmers, especially with women farmers, to identify resource and other constraints and locally appropriate ways to promote home gardens that are sustainable. To ensure that availability of garden foods translates into nutritional benefits for the whole family, nutrition education and information about nutritional value and utilization of fruits and vegetables in the diet are essential. Promotion of crop diversification requires flexibility regarding choice of species and cropping patterns, encouragement of diversity and cultivation of locally adapted varieties to enhance nutritional value, and attention to soil fertility, pest management, income-earning potential and genetic conservation. Involving women in all aspects of garden management and nutrition training is crucial, as women do most of the work and are responsible for family nutrition. Regular monitoring of garden progress, although costly, could help to resolve problems and to provide information quantifying gardening output and consumption increases it could thus contribute towards inducing policy-makers and planners to direct more investment to the improvement of the home-gardening sector's output. Community organizing for gardening, preferably building on local farmers' and women's organizations, is also a clear prerequisite for sustainability of gardens in the long term.

Urban agriculture

In urban areas the households most at risk of food insecurity and chronic malnutrition belong to the lowest-income groups which cannot afford to purchase adequate food. Many of these households comprise families of recent migrants who have failed to find regular employment. Their income levels are often so low that they can afford to purchase only the cheapest and most basic foods, and since they cannot afford to rent housing they are forced to camp in makeshift shanty towns on the periphery of cities. Such families often cultivate tiny plots of land within their household area and keep small livestock as a basic survival strategy. However, many of the better-established urban residents have also developed their own subsidiary food supply systems which support food purchase from the urban markets.

Urban agriculture, like the street food trade, often tends to be discounted and frowned upon in official circles as a limited, transitory phenomenon practiced only by recent migrants, living in squatter areas, who have not yet adapted to a market economy. In contradiction to this view, a survey covering cities in a number of countries including Ethiopia, Kenya, Senegal, the United Republic of Tanzania and Uganda (IDRC, 1993) showed that urban agriculture makes a significant contribution to the food supplies of many major cities. A Zambian survey showed that urban enterprises can improve household food security, the variety of the diet and intakes of essential micronutrients (see Box 19 and Tables 28 and 29).

Peri-urban commercial cultivation of high-value crops, including tomatoes, onions, green vegetables and fruit, is a growing food supply enterprise for a number of African cities. Such production systems can be very profitable, justifying their high costs in terms of inputs such as irrigation, fertilizers and pesticides. The proximity of production to urban markets is essential to ensure the freshness of such perishable commodities and their contribution of vitamins and minerals to urban diets.

By practicing a diversified form of urban agriculture, poor urban workers are able to meet some of their nutritional requirements, especially those for minerals and vitamins, through the consumption of some of their produce. This capability is important, as marketed vegetables and fruits often tend to be too expensive for low-income urban dwellers. To encourage urban food gardening as a viable food security strategy, assistance is needed in many instances to provide better access to land, water, seeds, community-based extension services, nutrition education and markets.

Box 19 - Survey of urban agriculture in Lusaka, Zambia

Surveys were carried out in low-income areas of Lusaka, which are made up of five types of settlement: two types of squatter areas (A and B), one of which (A) lacks even basic services two types of serviced plots (C and D), one provided by the local authorities (C), and the other provided under a World Bank housing plan (D) and an area of official low-cost public housing (E).

The questionnaire was designed to provide information about the following types of urban cultivation:

· irrigated plot gardens in the back andlor front yard which are cultivated all the year round

· rainy-season gardens, which are usually located on the periphery of the city, i.e. a type of urban allotment, dependent entirely on rain-fed production.

Analysis showed that nearly 60 percent of the low-income households cultivated one or both types of garden (Table 28). The variety of produce from both types of garden is shown in Table 29.

Source: Adapted from Sanyal, 1985.

Table 28 - Extent of urban agriculture in Lusaka, Zambia (percentage of households engaged)


Chapter 5 - Promotion of food and dietary diversification strategies to enhance and sustain household food security

Many people lack adequate amounts of foods that are rich in the nutrients needed for health and a productive life. Chronic undernutrition affects some 215 million people in sub-Saharan Africa, or 43 percent of the population (FAO, 1996b). Deficiencies of iron, vitamin A and iodine are also widespread about 300 million people are affected every year, and a much greater number are at risk of these deficiencies. Malnutrition increases people's vulnerability to infections, causing numerous deaths (see also Chapter 8). In the face of this bleak situation, major efforts are required by national governments and the international community to bring about reductions in malnutrition and micronutrient deficiencies.

Food diversification for stable access and a sustainable food supply

Increased food production and access are crucial to achieving major nutritional improvement. More foods should be produced that are rich in all the essential micronutrients, available in sufficient quantities and accessible to people all year round. This requires the collaboration of people working in agriculture, fishery, forestry, small animal husbandry, industry, marketing, communications, women's participation, home economics and nutrition. The wide application of proven technologies and approaches in these fields, as well as the development of new concepts, will contribute towards solving nutritional problems. The results of research must be transmitted to farmers, and efforts must be made to build on farmers' indigenous knowledge. Consumers, too, need to be involved and educated on how to prevent nutritional deficiencies.

Access to stable and sustainable food supplies is a precondition for the establishment of food security at the household level. Greater and more sustained yields from the farming system will increase the potential access of the household to an adequate diet. Similarly, farming practices that improve the regular flow of a variety of different foods into the household throughout the seasons enhance food security for its members. Promoting appropriate and improved technologies for home preservation and drying of vegetables and fruits at home will reduce wastage and ensure better utilization of fresh produce (e.g. mangoes) available in abundance during the harvest season. Increased food processing through the establishment and strengthening of small-scale agro-industries can contribute to the year-round availability and variety of micronutrient-rich foods in rural and urban markets. Agro-processing industries will not only even out seasonal price fluctuations, but will also create jobs and incomes from such activities as processing, storage, distribution and marketing. Agro-processing will also stimulate demand for farmers' crops and products and give consumers additional choice.

Strategies for food and dietary diversification at the community and household levels include a range of food-based activities that can maximize the availability of adequate amounts and greater variety of nutritious foods. These activities include:

· promotion of mixed cropping and integrated farming systems

· introduction of new crops (such as soybean)

· promotion of underexploited traditional foods and home gardens

· promotion of fishery and forestry products for household consumption

· promotion of improved preservation and storage of fruits and vegetables to reduce waste, post-harvest losses and effects of seasonality

· strengthening of small-scale agro-processing and food industries

· nutrition education to encourage the consumption of a healthy and nutritious diet year round.

Some of these strategies are discussed in this chapter. Diversification must entail management and generation of resources in such a way that all the various measures undertaken collectively work to improve the livelihood of the rural poor.

Mixed cropping

Traditional farming systems already use a diversity of crops in both mixed and relay intercropping as well as integration of crops with livestock and/or aquaculture. Research on cropping patterns and rotations is generating improved methods to ensure greater and more sustained yields. A holistic approach to research on farming systems, combining knowledge of socio-economic constraints and a better understanding of small farmers' conditions, should help in finding solutions.

For small-scale producers, mixed cropping can be associated with potential yield improvements and monetary advantages as well as positive implications for food security, dietary balance and nutrition. Mixed cropping reduces the risk of crop failure. It can also reduce the need for expensive inputs if crop residues from leguminous intercrops, supplemented where appropriate with rock phosphate, are returned to the soil. Mixed and/or rotational cropping offers increased protection from disease and pest damage, thus potentially increasing profitability and income. All of these attributes reduce risk in the food supply system and thus favourably influence food security.

Farming systems based on mixed cropping can extend the harvesting period and help to alleviate seasonal food shortages, thus enhancing the stability of household food access. They can also reduce erosion risks by providing increased soil cover and additional crop residues for use as green manure and mulch. Such characteristics offer gains in sustainability and in stability for the food supply system.

The choice of intercrops usually includes legumes and/or oilseeds such as melon seed, groundnut, soybean or sunflower, together with cereals as the dominant crop. In terms of dietary balance, grain legumes, or pulses, contain more protein than cereals and about ten times as much protein as most roots and tubers (Table 22). More significantly, in composition the proteins in cereals and legumes are complementary to each other.

Proteins are not all equally effective in promoting growth. The quality of a protein is determined by the kind of amino acids it contains and the proportion in which they are present. Good-quality proteins contain all the essential amino acids in proportions capable of promoting growth when they are the only proteins in the diet. Such proteins are known as complete proteins or proteins of high biological value. All animal proteins are complete proteins, and if eaten in adequate amounts they meet all a person's protein needs. Proteins from vegetable sources, such as beans, contain all the essential amino acids, but contain one or more of them in insufficient quantity to meet the needs for growth. Bean proteins are generally rich in lysine, an amino acid often deficient in cereal proteins, and legume proteins are therefore valuable supplements to cereal-based diets. Table 23 shows the amino acid composition and amino acid score of wheat and chickpea (Cicer arietinum), separately and in combination. An optimal protein quality can be obtained by combining wheat and chickpea at a ratio of approximately 2:1.

Table 22 - Comparative energy and protein content of some cereals, tubers, legumes and oilseeds (per 100 g)

Source: FAO/United States Department of Health. Education and Welfare, 1968.

The total protein content of different legumes varies widely, from around 12 percent for some varieties of chickpea to over 35 percent for high-protein cultivars of winged bean (Psophocarpus tetragonolobus) and soybean (Glycine max) (Table 24). Protein content also varies widely among different varieties of the same species. For example, the protein content of pigeon pea (Cajanus cajan) can vary from 13 to 20 percent, depending on the cultivar and the conditions of cultivation.

Table 23 - Essential amino acid content of wheat and chickpea (Cicer arietinum) (mg per g nitrogen in the food)

Source: Siegel and Fawcett, 1976 (quoted in FAO, 1989f).

a Amino acid score = amino acid content in wheat/chickpea mixture - amino acid content in ideal protein (egg) x 100.

Table 24 - Proximate composition of mature, dry winged bean seeds, compared with some commercial dry legume seeds (%)

Source: Vietmeyer, 1975 (quoted in FAO, 1989f).

The diversity of food supplies offered by mixed cropping systems accords well with nutritional security, especially since the young leaves of many grain legumes, such as cowpea, are also utilized as a green vegetable, providing essential minerals such as calcium and iron together with useful amounts of vitamins A and C. Table 25 lists some specific nutrients found in the major plant groups.

Improving mixed cropping technologies through farming systems studies and adaptive research

Farming systems research can contribute to the nutritional wellbeing and food security of households in a number of ways. With its comprehensive, interdisciplinary nature and its aim to improve the viability of small farms, such research is geared towards promoting sustainable livelihoods. It also includes a priority focus on increasing household food production and improving the assets of the farm household.

Farming systems research is directed towards improving the access of farm households to food and income through interventions related to choice of crops and cropping practices, increased use of small livestock, development of labour-saving technologies and improved storage and processing techniques. Thus strategies to encourage food diversification, such as promotion of mixed cropping technologies (including systems integrating crops with livestock and/or aquaculture), should include support for farming systems research and for the efforts of adaptive research planning teams which work directly with farmers in developing locally appropriate systems of integrated farming. Specific emphasis should be given in farming systems research to increasing the micronutrient output of agricultural systems and developing effective storage and preservation techniques for fruits and vegetables that can be employed at the household and community levels.

Table 25 - Specific nutrients found in the major plant groups

Carbohydrates, protein, dietary fibre, a vitamin B complex, a iron, a calcium a

Carbohydrates, protein, some vitamin C

Carbohydrates, protein, dietary fibre, a iron, a calcium, a vitamin B complex a

Vitamin C, vitamin A, iron, calcium, vitamin B complex, dietary fibre

Note: The diets of vulnerable groups may be low in ail these nutrients.

a Particularly high nutrient values are found in the hull.

Support services and advocacy for mixed cropping

Improved agricultural practices for a wider variety of food crops, once disseminated and accepted by the producers, often need support if they are to be widely adopted. For the integration of nutrition objectives into farming systems research, such support may be needed at the policy level. Actors involved in providing support may include government agencies through extension services, together with financial institutions, agricultural banks, farmer groups, fertilizer and seed companies, food industries and other private-sector agencies who may wish to profit from policies for food diversification.

The aim must be to provide timely and appropriate inputs, advice and assistance to farmers and producers to maximize the returns and minimize the risks arising from adoption of new strategies. Development of improved seed, together with advice on cultural practices and required inputs, must generally be accompanied by increased access to low-interest credit and greater security of land tenure to reduce risks in marginal areas. Action will also be required to ensure effective demand and marketing.

Smallholder farmers are profit maximizers and will adopt improved technologies if they are not too risky and are profitable at an early stage in the adoption process. Risk is perceived not only in terms of monetary returns, but also in terms of the stability and sustainability of the household's livelihood, including access to food.

The adoption of strategies to improve the productivity of mixed farming systems, if successful, will create an increased supply of a variety of foods in excess of the immediate demand for food within the producer communities. Therefore, before a food diversification strategy is undertaken, it will be necessary to assess and ensure marketability of excess products. Consumer surveys regarding the promoted crops will be required, together with advocacy and nutrition education to stimulate demand among urban groups, who may have become unfamiliar with some traditional foodstuffs.

The United Nations University Institute for Natural Resources in Africa (UNU/INRA) has commissioned a series of studies in 14 African countries on indigenous food crops and other useful plants, to determine people's knowledge of indigenous crops, the use they make of them and the preparations that are made from them. The aim of the surveys is to provide data for determining the status of, and priorities and strategies for, research and training related to indigenous food crops. Such information would be useful in improving cropping systems utilizing indigenous food crops in planning to enhance sustainability, to reduce risks of crop failure, to diversify production to meet farmers' food needs and to ensure genetic conservation of indigenous African food crops and in promoting improved methods of cultivation, processing and preparation.

In the case of small-grained cereals such as millets and sorghum, improved processing techniques may be necessary to provide products for urban housewives, who have become used to the convenience of rice and of wheat-based baked products such as breads and biscuits. Development of appropriate snack foods based on a wide variety of crops will help provide a market to absorb anticipated surpluses. In addition, widespread dissemination of nutritional information about these products should accompany their marketing.

Many of the foodstuffs produced in diversified farming systems, such as roots and tubers, plantains and bananas, and fruits and leafy vegetables, are highly perishable. As their production is promoted, therefore, transport and marketing facilities need to be enhanced to avoid post-harvest losses, whose high cost is inevitably passed on to the consumer. Agricultural policies favouring diversification should ideally entail a review of all sectors of the food chain from production to consumption, as well as mobilization of support at the national, district and community levels through producer and consumer interest groups.

Gardening for food

In many agricultural communities, people rely on one main staple crop whose seasonality implies a period of food shortage, usually referred to as the lean or the hungry season. Home gardening can often supplement family food supplies during lean periods and can generate added income when other sources of employment and income may be limited, provided enough water is available. Home gardens have mostly been maintained by women, who often water and manure them from domestic wastes and use them to produce early crops such as green maize and the fruits, spices and vegetables needed to prepare relishes.

Home gardens are labour intensive, but as they are usually close to the house, the labour required can be combined with home and child care responsibilities. Children are often responsible for carrying water and for simple maintenance work, and they may also be given a few plants or a small area to tend. Support of home gardening through horticultural training and nutrition education at school, including the establishment and maintenance of a school food production garden, will provide useful training in intensive land management for the next generation.

Home gardening is quickly taking different forms to suit individual lifestyles and work patterns. For example, urban dwellers grow maize in the backyard and quite often in the front garden as well busy traders plant bananas behind their roadside stalls and scatter tomato seeds in damp areas around their compound living area and children bury mango seeds in rubbish heaps and in drains at the side of their houses. Gardening is often rather haphazard and disorganized at this level, with chickens and goats competing for the harvest, but the intention and interest in home gardening are there, waiting to be harnessed.

Unfortunately, home gardens have rarely received official recognition, and families often lack the necessary resources, knowledge and inputs to produce crops as effectively as possible. A survey in Ghana indicated that traditional home garden farming systems have a number of major constraints which need to be removed if the systems are to be successfully promoted (Asare, Oppong and Twum-Ampofo, 1985). Important factors to consider in encouraging the expansion of home gardens include security of land tenure to facilitate long-term investment in home gardens and better extension services, including credit, to promote the wider establishment of home gardens and improve their management.

Home gardens and nutrition

Traditional home gardens continue to be important sources of micronutrients for rural communities. Poor people obtain most of their nutrients from food plants, which are cheaper and more accessible than animal foods. In humid tropical countries, green leafy plants such as Amaranthus s pp., Corchorus spp., Bidens pilosa, Gynandropsis spp., Celosia spp., Basella spp., Solanum scabrum, Solanum americanum, Hibiscus sabdariffa and Vigna unguiculata often grow wild and spontaneously. Traditionally, they have been consumed as leafy vegetables when climatic conditions have made the cultivation of exotic vegetables more difficult. The leaves of these plants tend to be good sources of protein, phosphorus and iron as well as vitamins A and C and in some cases B-group vitamins. In many cases they are of higher overall food value than introduced vegetable species, for example cabbage or tomatoes. Table 26 shows the nutritional content of some green leafy vegetables widely used in Africa.

Through careful selection, a range of fruit and vegetable crops can be cultivated throughout the year to provide a constant supply of micronutrients (see Figure 19). For example, yellow and orange perennial fruits (e.g. mango, papaya, cape gooseberry and guava), fruit vegetables (e.g. tomato, pumpkin, squash, gourd and eggplant), some root vegetables (e.g. carrot and yellow-fleshed sweet potato) and most dark-green leafy vegetables are generally moderate to good sources of vitamins A and C. Also, some leaves and fruits produced by local indigenous trees are consumed in rural areas and are rich in micronutrients, e.g. guavas and loquats. Some sources of nutrition from the home garden are given in Table 27.

Some staple foods also have a role as sources of micronutrients. For instance, leaves of roots and tubers are valuable sources. In many countries of the African humid tropics, leaves of cassava (Manihot esculenta) are also consumed. Millets are rich sources of iron in comparison with other cereals such as wheat or maize.

Fruit and vegetable cultivation presents rather different challenges under low-temperature conditions such as those found in the remote highlands of Ethiopia or Lesotho. In such areas, efforts to extend the production of leafy vegetables into the winter season, for example, need to be based on the selection of cold-tolerant cultivars of Brassica crops such as kale and mustard. Alternatively, it might be advisable to adopt locally appropriate protected cultivation practices, such as the use of simple low plastic tunnels or hotbeds which accumulate solar heat and shield crop plants from exposure to extremely low temperature and wind.

Table 26 - Nutritional content of some green leafy vegetables (per 100 g edible portion)

Baobab leaves (Adansonia digitata)

Bitter feat (Vernonia amygdalina)

Cassava leaf (Manihot esculenta)

Cat's whiskers (Cleome gynandra)

Sweet potato (Ipomoea batatas)

Leaves, cooked, plus groundnuts

FIGURE 19 - Food availability from home food production and supply systems, Nchelenge, Zambia

Source: Adapted from Thuvesson, 1988.

Table 27 - Some sources of nutrition from the home garden

Source: Adapted from WHO/UNICEF, 1985.

For fruit and vegetable crops, staggering planting dates in the case of short-cycle crops and choosing a mixture of early maturing, average and late-maturing varieties for both annual and perennial crops can extend the harvest period. For instance, some varieties of mango tree can be harvested three times a year, with flowering, first budding, ripening and harvesting stages occurring simultaneously on different parts of the same tree. Thus the problem of seasonality of available nutrients, in this case primarily beta-carotene, can be overcome.

Role of women in home gardening

The role of women in home and community gardens is of special importance. In addition to being responsible for producing crops on small plots of land, women, especially those who are elderly, often have good knowledge of indigenous species of green leafy vegetables they know how to prepare them and how to preserve both seeds and produce. In local markets, the main vendors of these crops (fresh or dried) are often women.

Extension services unfortunately tend to focus on the major field crops. Improved planting materials, better cultivars and advice on cultural practices are rarely offered to cultivators of home gardens. Since women do the bulk of the work and are more conscious of and concerned with the nutritional needs of the family, extension advice, credit and agricultural inputs should be provided to them for maximum benefits. The organization of women's groups should be promoted to facilitate their access to inputs, to improve the efficiency of their work and thus to improve the diversity and productivity of gardens.

Home gardening as a development strategy

It is important to distinguish between traditional gardens, which are cultivated independently of any intervention, and promoted gardens, which receive external assistance. Many gardening projects, especially those that promote home gardening for nutritional and income-generating benefits, are supported by external donors and non-governmental organizations (NGOs). The involvement of ministries of agriculture has generally been limited, as horticulture is still given a low priority in overall agricultural development programmes, and home gardening, in spite of its potential output, receives even less attention. Consequently, few agricultural extensionists have been trained in gardening techniques, and even fewer in mixed tropical gardening. Still fewer have the knowledge to promote better diets and nutritional practices.

The neglect of gardening in development strategies is partly explained by the paucity of data on the output of traditional home gardening systems expressed in quantitative and monetary-equivalent terms which could demonstrate a significant contribution to economic output and national development. As a result, most agricultural and research programmes tend to underestimate or discount the actual or potential importance of home gardening as a food security strategy, and in particular as a strategy for meeting micronutrient needs.

However, as more evidence showing the social, economic and nutritional benefits of home gardening is becoming available, some governments and the private sector are showing renewed interest in gardening activities. Case-studies from Bangladesh and Central America that examined the socio-economic aspects of home gardening and its contribution to family consumption and income provide strong evidence that home gardening has significant economic benefits and that it can be a viable strategy for increasing food supplies for family consumption (Marsh, 1994).

In an integrated nutrition/home gardening programme supported by Helen Keller International in Bangladesh, overall vegetable consumption increased by 30 percent, with home gardens supplying 80 percent of vegetables consumed by the family. As most of the income earned from sale of home garden produce was spent on food, the prevalence of malnutrition among children of participating families was also reduced. In a study in Honduras and Nicaragua, the gardens supplied a significant proportion of fruits and vegetables, legumes, roots and tubers, coffee, tea and medicinal plants for home consumption. The combined benefits of home consumption, income earned from sale of garden produce (25 percent of total average income in Bangladesh, although wide variation was recorded in Honduras and Nicaragua) and savings in expenditure on garden produce were judged to make a significant contribution to the household economy.

Data from an FAO-supported project in the Niger promoting the production and consumption of vitamin A-rich foods among women's groups and their families showed that the proportion of healthy children increased in the project areas, in comparison with the non-project villages (IVACG, 1994). The successful ingredients of this project were: a strong emphasis on nutrition education to promote underutilized indigenous foods such as green leaves the cultivation of traditional wild sources of vitamin A and the use of food preservation and solar drying to address the problem of seasonal shortages.

Available evidence clearly suggests that home gardening can result in tangible benefits for the household, including food on the table, extra income and healthy children. Access to home-grown fruits, vegetables, small animals and/or fish ensures a more balanced diet for rural families with limited purchasing power and increases their self-reliance. The sale of surpluses can provide direct benefits to producers, especially women farmers, and can also benefit consumers by increasing the quantity and diversity of food supplies in local markets. In communities where specific nutritional deficiencies persist or where there appear to be unexploited possibilities for income generation, households can with some support from government services or NGOs improve the diversity and productivity of their traditional gardens. Home gardening can also be a potentially important element in urban food security strategies.

For home garden projects to be successful and sustainable, a number of important elements need to be considered. Since home gardening is a complex and varied production system forming part of a wider household economy, garden interventions to improve nutrition require a good understanding of local conditions so that project goals can be adapted locally. Thus it is necessary to work closely with local farmers, especially with women farmers, to identify resource and other constraints and locally appropriate ways to promote home gardens that are sustainable. To ensure that availability of garden foods translates into nutritional benefits for the whole family, nutrition education and information about nutritional value and utilization of fruits and vegetables in the diet are essential. Promotion of crop diversification requires flexibility regarding choice of species and cropping patterns, encouragement of diversity and cultivation of locally adapted varieties to enhance nutritional value, and attention to soil fertility, pest management, income-earning potential and genetic conservation. Involving women in all aspects of garden management and nutrition training is crucial, as women do most of the work and are responsible for family nutrition. Regular monitoring of garden progress, although costly, could help to resolve problems and to provide information quantifying gardening output and consumption increases it could thus contribute towards inducing policy-makers and planners to direct more investment to the improvement of the home-gardening sector's output. Community organizing for gardening, preferably building on local farmers' and women's organizations, is also a clear prerequisite for sustainability of gardens in the long term.

Urban agriculture

In urban areas the households most at risk of food insecurity and chronic malnutrition belong to the lowest-income groups which cannot afford to purchase adequate food. Many of these households comprise families of recent migrants who have failed to find regular employment. Their income levels are often so low that they can afford to purchase only the cheapest and most basic foods, and since they cannot afford to rent housing they are forced to camp in makeshift shanty towns on the periphery of cities. Such families often cultivate tiny plots of land within their household area and keep small livestock as a basic survival strategy. However, many of the better-established urban residents have also developed their own subsidiary food supply systems which support food purchase from the urban markets.

Urban agriculture, like the street food trade, often tends to be discounted and frowned upon in official circles as a limited, transitory phenomenon practiced only by recent migrants, living in squatter areas, who have not yet adapted to a market economy. In contradiction to this view, a survey covering cities in a number of countries including Ethiopia, Kenya, Senegal, the United Republic of Tanzania and Uganda (IDRC, 1993) showed that urban agriculture makes a significant contribution to the food supplies of many major cities. A Zambian survey showed that urban enterprises can improve household food security, the variety of the diet and intakes of essential micronutrients (see Box 19 and Tables 28 and 29).

Peri-urban commercial cultivation of high-value crops, including tomatoes, onions, green vegetables and fruit, is a growing food supply enterprise for a number of African cities. Such production systems can be very profitable, justifying their high costs in terms of inputs such as irrigation, fertilizers and pesticides. The proximity of production to urban markets is essential to ensure the freshness of such perishable commodities and their contribution of vitamins and minerals to urban diets.

By practicing a diversified form of urban agriculture, poor urban workers are able to meet some of their nutritional requirements, especially those for minerals and vitamins, through the consumption of some of their produce. This capability is important, as marketed vegetables and fruits often tend to be too expensive for low-income urban dwellers. To encourage urban food gardening as a viable food security strategy, assistance is needed in many instances to provide better access to land, water, seeds, community-based extension services, nutrition education and markets.

Box 19 - Survey of urban agriculture in Lusaka, Zambia

Surveys were carried out in low-income areas of Lusaka, which are made up of five types of settlement: two types of squatter areas (A and B), one of which (A) lacks even basic services two types of serviced plots (C and D), one provided by the local authorities (C), and the other provided under a World Bank housing plan (D) and an area of official low-cost public housing (E).

The questionnaire was designed to provide information about the following types of urban cultivation:

· irrigated plot gardens in the back andlor front yard which are cultivated all the year round

· rainy-season gardens, which are usually located on the periphery of the city, i.e. a type of urban allotment, dependent entirely on rain-fed production.

Analysis showed that nearly 60 percent of the low-income households cultivated one or both types of garden (Table 28). The variety of produce from both types of garden is shown in Table 29.

Source: Adapted from Sanyal, 1985.

Table 28 - Extent of urban agriculture in Lusaka, Zambia (percentage of households engaged)


Chapter 5 - Promotion of food and dietary diversification strategies to enhance and sustain household food security

Many people lack adequate amounts of foods that are rich in the nutrients needed for health and a productive life. Chronic undernutrition affects some 215 million people in sub-Saharan Africa, or 43 percent of the population (FAO, 1996b). Deficiencies of iron, vitamin A and iodine are also widespread about 300 million people are affected every year, and a much greater number are at risk of these deficiencies. Malnutrition increases people's vulnerability to infections, causing numerous deaths (see also Chapter 8). In the face of this bleak situation, major efforts are required by national governments and the international community to bring about reductions in malnutrition and micronutrient deficiencies.

Food diversification for stable access and a sustainable food supply

Increased food production and access are crucial to achieving major nutritional improvement. More foods should be produced that are rich in all the essential micronutrients, available in sufficient quantities and accessible to people all year round. This requires the collaboration of people working in agriculture, fishery, forestry, small animal husbandry, industry, marketing, communications, women's participation, home economics and nutrition. The wide application of proven technologies and approaches in these fields, as well as the development of new concepts, will contribute towards solving nutritional problems. The results of research must be transmitted to farmers, and efforts must be made to build on farmers' indigenous knowledge. Consumers, too, need to be involved and educated on how to prevent nutritional deficiencies.

Access to stable and sustainable food supplies is a precondition for the establishment of food security at the household level. Greater and more sustained yields from the farming system will increase the potential access of the household to an adequate diet. Similarly, farming practices that improve the regular flow of a variety of different foods into the household throughout the seasons enhance food security for its members. Promoting appropriate and improved technologies for home preservation and drying of vegetables and fruits at home will reduce wastage and ensure better utilization of fresh produce (e.g. mangoes) available in abundance during the harvest season. Increased food processing through the establishment and strengthening of small-scale agro-industries can contribute to the year-round availability and variety of micronutrient-rich foods in rural and urban markets. Agro-processing industries will not only even out seasonal price fluctuations, but will also create jobs and incomes from such activities as processing, storage, distribution and marketing. Agro-processing will also stimulate demand for farmers' crops and products and give consumers additional choice.

Strategies for food and dietary diversification at the community and household levels include a range of food-based activities that can maximize the availability of adequate amounts and greater variety of nutritious foods. These activities include:

· promotion of mixed cropping and integrated farming systems

· introduction of new crops (such as soybean)

· promotion of underexploited traditional foods and home gardens

· promotion of fishery and forestry products for household consumption

· promotion of improved preservation and storage of fruits and vegetables to reduce waste, post-harvest losses and effects of seasonality

· strengthening of small-scale agro-processing and food industries

· nutrition education to encourage the consumption of a healthy and nutritious diet year round.

Some of these strategies are discussed in this chapter. Diversification must entail management and generation of resources in such a way that all the various measures undertaken collectively work to improve the livelihood of the rural poor.

Mixed cropping

Traditional farming systems already use a diversity of crops in both mixed and relay intercropping as well as integration of crops with livestock and/or aquaculture. Research on cropping patterns and rotations is generating improved methods to ensure greater and more sustained yields. A holistic approach to research on farming systems, combining knowledge of socio-economic constraints and a better understanding of small farmers' conditions, should help in finding solutions.

For small-scale producers, mixed cropping can be associated with potential yield improvements and monetary advantages as well as positive implications for food security, dietary balance and nutrition. Mixed cropping reduces the risk of crop failure. It can also reduce the need for expensive inputs if crop residues from leguminous intercrops, supplemented where appropriate with rock phosphate, are returned to the soil. Mixed and/or rotational cropping offers increased protection from disease and pest damage, thus potentially increasing profitability and income. All of these attributes reduce risk in the food supply system and thus favourably influence food security.

Farming systems based on mixed cropping can extend the harvesting period and help to alleviate seasonal food shortages, thus enhancing the stability of household food access. They can also reduce erosion risks by providing increased soil cover and additional crop residues for use as green manure and mulch. Such characteristics offer gains in sustainability and in stability for the food supply system.

The choice of intercrops usually includes legumes and/or oilseeds such as melon seed, groundnut, soybean or sunflower, together with cereals as the dominant crop. In terms of dietary balance, grain legumes, or pulses, contain more protein than cereals and about ten times as much protein as most roots and tubers (Table 22). More significantly, in composition the proteins in cereals and legumes are complementary to each other.

Proteins are not all equally effective in promoting growth. The quality of a protein is determined by the kind of amino acids it contains and the proportion in which they are present. Good-quality proteins contain all the essential amino acids in proportions capable of promoting growth when they are the only proteins in the diet. Such proteins are known as complete proteins or proteins of high biological value. All animal proteins are complete proteins, and if eaten in adequate amounts they meet all a person's protein needs. Proteins from vegetable sources, such as beans, contain all the essential amino acids, but contain one or more of them in insufficient quantity to meet the needs for growth. Bean proteins are generally rich in lysine, an amino acid often deficient in cereal proteins, and legume proteins are therefore valuable supplements to cereal-based diets. Table 23 shows the amino acid composition and amino acid score of wheat and chickpea (Cicer arietinum), separately and in combination. An optimal protein quality can be obtained by combining wheat and chickpea at a ratio of approximately 2:1.

Table 22 - Comparative energy and protein content of some cereals, tubers, legumes and oilseeds (per 100 g)

Source: FAO/United States Department of Health. Education and Welfare, 1968.

The total protein content of different legumes varies widely, from around 12 percent for some varieties of chickpea to over 35 percent for high-protein cultivars of winged bean (Psophocarpus tetragonolobus) and soybean (Glycine max) (Table 24). Protein content also varies widely among different varieties of the same species. For example, the protein content of pigeon pea (Cajanus cajan) can vary from 13 to 20 percent, depending on the cultivar and the conditions of cultivation.

Table 23 - Essential amino acid content of wheat and chickpea (Cicer arietinum) (mg per g nitrogen in the food)

Source: Siegel and Fawcett, 1976 (quoted in FAO, 1989f).

a Amino acid score = amino acid content in wheat/chickpea mixture - amino acid content in ideal protein (egg) x 100.

Table 24 - Proximate composition of mature, dry winged bean seeds, compared with some commercial dry legume seeds (%)

Source: Vietmeyer, 1975 (quoted in FAO, 1989f).

The diversity of food supplies offered by mixed cropping systems accords well with nutritional security, especially since the young leaves of many grain legumes, such as cowpea, are also utilized as a green vegetable, providing essential minerals such as calcium and iron together with useful amounts of vitamins A and C. Table 25 lists some specific nutrients found in the major plant groups.

Improving mixed cropping technologies through farming systems studies and adaptive research

Farming systems research can contribute to the nutritional wellbeing and food security of households in a number of ways. With its comprehensive, interdisciplinary nature and its aim to improve the viability of small farms, such research is geared towards promoting sustainable livelihoods. It also includes a priority focus on increasing household food production and improving the assets of the farm household.

Farming systems research is directed towards improving the access of farm households to food and income through interventions related to choice of crops and cropping practices, increased use of small livestock, development of labour-saving technologies and improved storage and processing techniques. Thus strategies to encourage food diversification, such as promotion of mixed cropping technologies (including systems integrating crops with livestock and/or aquaculture), should include support for farming systems research and for the efforts of adaptive research planning teams which work directly with farmers in developing locally appropriate systems of integrated farming. Specific emphasis should be given in farming systems research to increasing the micronutrient output of agricultural systems and developing effective storage and preservation techniques for fruits and vegetables that can be employed at the household and community levels.

Table 25 - Specific nutrients found in the major plant groups

Carbohydrates, protein, dietary fibre, a vitamin B complex, a iron, a calcium a

Carbohydrates, protein, some vitamin C

Carbohydrates, protein, dietary fibre, a iron, a calcium, a vitamin B complex a

Vitamin C, vitamin A, iron, calcium, vitamin B complex, dietary fibre

Note: The diets of vulnerable groups may be low in ail these nutrients.

a Particularly high nutrient values are found in the hull.

Support services and advocacy for mixed cropping

Improved agricultural practices for a wider variety of food crops, once disseminated and accepted by the producers, often need support if they are to be widely adopted. For the integration of nutrition objectives into farming systems research, such support may be needed at the policy level. Actors involved in providing support may include government agencies through extension services, together with financial institutions, agricultural banks, farmer groups, fertilizer and seed companies, food industries and other private-sector agencies who may wish to profit from policies for food diversification.

The aim must be to provide timely and appropriate inputs, advice and assistance to farmers and producers to maximize the returns and minimize the risks arising from adoption of new strategies. Development of improved seed, together with advice on cultural practices and required inputs, must generally be accompanied by increased access to low-interest credit and greater security of land tenure to reduce risks in marginal areas. Action will also be required to ensure effective demand and marketing.

Smallholder farmers are profit maximizers and will adopt improved technologies if they are not too risky and are profitable at an early stage in the adoption process. Risk is perceived not only in terms of monetary returns, but also in terms of the stability and sustainability of the household's livelihood, including access to food.

The adoption of strategies to improve the productivity of mixed farming systems, if successful, will create an increased supply of a variety of foods in excess of the immediate demand for food within the producer communities. Therefore, before a food diversification strategy is undertaken, it will be necessary to assess and ensure marketability of excess products. Consumer surveys regarding the promoted crops will be required, together with advocacy and nutrition education to stimulate demand among urban groups, who may have become unfamiliar with some traditional foodstuffs.

The United Nations University Institute for Natural Resources in Africa (UNU/INRA) has commissioned a series of studies in 14 African countries on indigenous food crops and other useful plants, to determine people's knowledge of indigenous crops, the use they make of them and the preparations that are made from them. The aim of the surveys is to provide data for determining the status of, and priorities and strategies for, research and training related to indigenous food crops. Such information would be useful in improving cropping systems utilizing indigenous food crops in planning to enhance sustainability, to reduce risks of crop failure, to diversify production to meet farmers' food needs and to ensure genetic conservation of indigenous African food crops and in promoting improved methods of cultivation, processing and preparation.

In the case of small-grained cereals such as millets and sorghum, improved processing techniques may be necessary to provide products for urban housewives, who have become used to the convenience of rice and of wheat-based baked products such as breads and biscuits. Development of appropriate snack foods based on a wide variety of crops will help provide a market to absorb anticipated surpluses. In addition, widespread dissemination of nutritional information about these products should accompany their marketing.

Many of the foodstuffs produced in diversified farming systems, such as roots and tubers, plantains and bananas, and fruits and leafy vegetables, are highly perishable. As their production is promoted, therefore, transport and marketing facilities need to be enhanced to avoid post-harvest losses, whose high cost is inevitably passed on to the consumer. Agricultural policies favouring diversification should ideally entail a review of all sectors of the food chain from production to consumption, as well as mobilization of support at the national, district and community levels through producer and consumer interest groups.

Gardening for food

In many agricultural communities, people rely on one main staple crop whose seasonality implies a period of food shortage, usually referred to as the lean or the hungry season. Home gardening can often supplement family food supplies during lean periods and can generate added income when other sources of employment and income may be limited, provided enough water is available. Home gardens have mostly been maintained by women, who often water and manure them from domestic wastes and use them to produce early crops such as green maize and the fruits, spices and vegetables needed to prepare relishes.

Home gardens are labour intensive, but as they are usually close to the house, the labour required can be combined with home and child care responsibilities. Children are often responsible for carrying water and for simple maintenance work, and they may also be given a few plants or a small area to tend. Support of home gardening through horticultural training and nutrition education at school, including the establishment and maintenance of a school food production garden, will provide useful training in intensive land management for the next generation.

Home gardening is quickly taking different forms to suit individual lifestyles and work patterns. For example, urban dwellers grow maize in the backyard and quite often in the front garden as well busy traders plant bananas behind their roadside stalls and scatter tomato seeds in damp areas around their compound living area and children bury mango seeds in rubbish heaps and in drains at the side of their houses. Gardening is often rather haphazard and disorganized at this level, with chickens and goats competing for the harvest, but the intention and interest in home gardening are there, waiting to be harnessed.

Unfortunately, home gardens have rarely received official recognition, and families often lack the necessary resources, knowledge and inputs to produce crops as effectively as possible. A survey in Ghana indicated that traditional home garden farming systems have a number of major constraints which need to be removed if the systems are to be successfully promoted (Asare, Oppong and Twum-Ampofo, 1985). Important factors to consider in encouraging the expansion of home gardens include security of land tenure to facilitate long-term investment in home gardens and better extension services, including credit, to promote the wider establishment of home gardens and improve their management.

Home gardens and nutrition

Traditional home gardens continue to be important sources of micronutrients for rural communities. Poor people obtain most of their nutrients from food plants, which are cheaper and more accessible than animal foods. In humid tropical countries, green leafy plants such as Amaranthus s pp., Corchorus spp., Bidens pilosa, Gynandropsis spp., Celosia spp., Basella spp., Solanum scabrum, Solanum americanum, Hibiscus sabdariffa and Vigna unguiculata often grow wild and spontaneously. Traditionally, they have been consumed as leafy vegetables when climatic conditions have made the cultivation of exotic vegetables more difficult. The leaves of these plants tend to be good sources of protein, phosphorus and iron as well as vitamins A and C and in some cases B-group vitamins. In many cases they are of higher overall food value than introduced vegetable species, for example cabbage or tomatoes. Table 26 shows the nutritional content of some green leafy vegetables widely used in Africa.

Through careful selection, a range of fruit and vegetable crops can be cultivated throughout the year to provide a constant supply of micronutrients (see Figure 19). For example, yellow and orange perennial fruits (e.g. mango, papaya, cape gooseberry and guava), fruit vegetables (e.g. tomato, pumpkin, squash, gourd and eggplant), some root vegetables (e.g. carrot and yellow-fleshed sweet potato) and most dark-green leafy vegetables are generally moderate to good sources of vitamins A and C. Also, some leaves and fruits produced by local indigenous trees are consumed in rural areas and are rich in micronutrients, e.g. guavas and loquats. Some sources of nutrition from the home garden are given in Table 27.

Some staple foods also have a role as sources of micronutrients. For instance, leaves of roots and tubers are valuable sources. In many countries of the African humid tropics, leaves of cassava (Manihot esculenta) are also consumed. Millets are rich sources of iron in comparison with other cereals such as wheat or maize.

Fruit and vegetable cultivation presents rather different challenges under low-temperature conditions such as those found in the remote highlands of Ethiopia or Lesotho. In such areas, efforts to extend the production of leafy vegetables into the winter season, for example, need to be based on the selection of cold-tolerant cultivars of Brassica crops such as kale and mustard. Alternatively, it might be advisable to adopt locally appropriate protected cultivation practices, such as the use of simple low plastic tunnels or hotbeds which accumulate solar heat and shield crop plants from exposure to extremely low temperature and wind.

Table 26 - Nutritional content of some green leafy vegetables (per 100 g edible portion)

Baobab leaves (Adansonia digitata)

Bitter feat (Vernonia amygdalina)

Cassava leaf (Manihot esculenta)

Cat's whiskers (Cleome gynandra)

Sweet potato (Ipomoea batatas)

Leaves, cooked, plus groundnuts

FIGURE 19 - Food availability from home food production and supply systems, Nchelenge, Zambia

Source: Adapted from Thuvesson, 1988.

Table 27 - Some sources of nutrition from the home garden

Source: Adapted from WHO/UNICEF, 1985.

For fruit and vegetable crops, staggering planting dates in the case of short-cycle crops and choosing a mixture of early maturing, average and late-maturing varieties for both annual and perennial crops can extend the harvest period. For instance, some varieties of mango tree can be harvested three times a year, with flowering, first budding, ripening and harvesting stages occurring simultaneously on different parts of the same tree. Thus the problem of seasonality of available nutrients, in this case primarily beta-carotene, can be overcome.

Role of women in home gardening

The role of women in home and community gardens is of special importance. In addition to being responsible for producing crops on small plots of land, women, especially those who are elderly, often have good knowledge of indigenous species of green leafy vegetables they know how to prepare them and how to preserve both seeds and produce. In local markets, the main vendors of these crops (fresh or dried) are often women.

Extension services unfortunately tend to focus on the major field crops. Improved planting materials, better cultivars and advice on cultural practices are rarely offered to cultivators of home gardens. Since women do the bulk of the work and are more conscious of and concerned with the nutritional needs of the family, extension advice, credit and agricultural inputs should be provided to them for maximum benefits. The organization of women's groups should be promoted to facilitate their access to inputs, to improve the efficiency of their work and thus to improve the diversity and productivity of gardens.

Home gardening as a development strategy

It is important to distinguish between traditional gardens, which are cultivated independently of any intervention, and promoted gardens, which receive external assistance. Many gardening projects, especially those that promote home gardening for nutritional and income-generating benefits, are supported by external donors and non-governmental organizations (NGOs). The involvement of ministries of agriculture has generally been limited, as horticulture is still given a low priority in overall agricultural development programmes, and home gardening, in spite of its potential output, receives even less attention. Consequently, few agricultural extensionists have been trained in gardening techniques, and even fewer in mixed tropical gardening. Still fewer have the knowledge to promote better diets and nutritional practices.

The neglect of gardening in development strategies is partly explained by the paucity of data on the output of traditional home gardening systems expressed in quantitative and monetary-equivalent terms which could demonstrate a significant contribution to economic output and national development. As a result, most agricultural and research programmes tend to underestimate or discount the actual or potential importance of home gardening as a food security strategy, and in particular as a strategy for meeting micronutrient needs.

However, as more evidence showing the social, economic and nutritional benefits of home gardening is becoming available, some governments and the private sector are showing renewed interest in gardening activities. Case-studies from Bangladesh and Central America that examined the socio-economic aspects of home gardening and its contribution to family consumption and income provide strong evidence that home gardening has significant economic benefits and that it can be a viable strategy for increasing food supplies for family consumption (Marsh, 1994).

In an integrated nutrition/home gardening programme supported by Helen Keller International in Bangladesh, overall vegetable consumption increased by 30 percent, with home gardens supplying 80 percent of vegetables consumed by the family. As most of the income earned from sale of home garden produce was spent on food, the prevalence of malnutrition among children of participating families was also reduced. In a study in Honduras and Nicaragua, the gardens supplied a significant proportion of fruits and vegetables, legumes, roots and tubers, coffee, tea and medicinal plants for home consumption. The combined benefits of home consumption, income earned from sale of garden produce (25 percent of total average income in Bangladesh, although wide variation was recorded in Honduras and Nicaragua) and savings in expenditure on garden produce were judged to make a significant contribution to the household economy.

Data from an FAO-supported project in the Niger promoting the production and consumption of vitamin A-rich foods among women's groups and their families showed that the proportion of healthy children increased in the project areas, in comparison with the non-project villages (IVACG, 1994). The successful ingredients of this project were: a strong emphasis on nutrition education to promote underutilized indigenous foods such as green leaves the cultivation of traditional wild sources of vitamin A and the use of food preservation and solar drying to address the problem of seasonal shortages.

Available evidence clearly suggests that home gardening can result in tangible benefits for the household, including food on the table, extra income and healthy children. Access to home-grown fruits, vegetables, small animals and/or fish ensures a more balanced diet for rural families with limited purchasing power and increases their self-reliance. The sale of surpluses can provide direct benefits to producers, especially women farmers, and can also benefit consumers by increasing the quantity and diversity of food supplies in local markets. In communities where specific nutritional deficiencies persist or where there appear to be unexploited possibilities for income generation, households can with some support from government services or NGOs improve the diversity and productivity of their traditional gardens. Home gardening can also be a potentially important element in urban food security strategies.

For home garden projects to be successful and sustainable, a number of important elements need to be considered. Since home gardening is a complex and varied production system forming part of a wider household economy, garden interventions to improve nutrition require a good understanding of local conditions so that project goals can be adapted locally. Thus it is necessary to work closely with local farmers, especially with women farmers, to identify resource and other constraints and locally appropriate ways to promote home gardens that are sustainable. To ensure that availability of garden foods translates into nutritional benefits for the whole family, nutrition education and information about nutritional value and utilization of fruits and vegetables in the diet are essential. Promotion of crop diversification requires flexibility regarding choice of species and cropping patterns, encouragement of diversity and cultivation of locally adapted varieties to enhance nutritional value, and attention to soil fertility, pest management, income-earning potential and genetic conservation. Involving women in all aspects of garden management and nutrition training is crucial, as women do most of the work and are responsible for family nutrition. Regular monitoring of garden progress, although costly, could help to resolve problems and to provide information quantifying gardening output and consumption increases it could thus contribute towards inducing policy-makers and planners to direct more investment to the improvement of the home-gardening sector's output. Community organizing for gardening, preferably building on local farmers' and women's organizations, is also a clear prerequisite for sustainability of gardens in the long term.

Urban agriculture

In urban areas the households most at risk of food insecurity and chronic malnutrition belong to the lowest-income groups which cannot afford to purchase adequate food. Many of these households comprise families of recent migrants who have failed to find regular employment. Their income levels are often so low that they can afford to purchase only the cheapest and most basic foods, and since they cannot afford to rent housing they are forced to camp in makeshift shanty towns on the periphery of cities. Such families often cultivate tiny plots of land within their household area and keep small livestock as a basic survival strategy. However, many of the better-established urban residents have also developed their own subsidiary food supply systems which support food purchase from the urban markets.

Urban agriculture, like the street food trade, often tends to be discounted and frowned upon in official circles as a limited, transitory phenomenon practiced only by recent migrants, living in squatter areas, who have not yet adapted to a market economy. In contradiction to this view, a survey covering cities in a number of countries including Ethiopia, Kenya, Senegal, the United Republic of Tanzania and Uganda (IDRC, 1993) showed that urban agriculture makes a significant contribution to the food supplies of many major cities. A Zambian survey showed that urban enterprises can improve household food security, the variety of the diet and intakes of essential micronutrients (see Box 19 and Tables 28 and 29).

Peri-urban commercial cultivation of high-value crops, including tomatoes, onions, green vegetables and fruit, is a growing food supply enterprise for a number of African cities. Such production systems can be very profitable, justifying their high costs in terms of inputs such as irrigation, fertilizers and pesticides. The proximity of production to urban markets is essential to ensure the freshness of such perishable commodities and their contribution of vitamins and minerals to urban diets.

By practicing a diversified form of urban agriculture, poor urban workers are able to meet some of their nutritional requirements, especially those for minerals and vitamins, through the consumption of some of their produce. This capability is important, as marketed vegetables and fruits often tend to be too expensive for low-income urban dwellers. To encourage urban food gardening as a viable food security strategy, assistance is needed in many instances to provide better access to land, water, seeds, community-based extension services, nutrition education and markets.

Box 19 - Survey of urban agriculture in Lusaka, Zambia

Surveys were carried out in low-income areas of Lusaka, which are made up of five types of settlement: two types of squatter areas (A and B), one of which (A) lacks even basic services two types of serviced plots (C and D), one provided by the local authorities (C), and the other provided under a World Bank housing plan (D) and an area of official low-cost public housing (E).

The questionnaire was designed to provide information about the following types of urban cultivation:

· irrigated plot gardens in the back andlor front yard which are cultivated all the year round

· rainy-season gardens, which are usually located on the periphery of the city, i.e. a type of urban allotment, dependent entirely on rain-fed production.

Analysis showed that nearly 60 percent of the low-income households cultivated one or both types of garden (Table 28). The variety of produce from both types of garden is shown in Table 29.

Source: Adapted from Sanyal, 1985.

Table 28 - Extent of urban agriculture in Lusaka, Zambia (percentage of households engaged)


Chapter 5 - Promotion of food and dietary diversification strategies to enhance and sustain household food security

Many people lack adequate amounts of foods that are rich in the nutrients needed for health and a productive life. Chronic undernutrition affects some 215 million people in sub-Saharan Africa, or 43 percent of the population (FAO, 1996b). Deficiencies of iron, vitamin A and iodine are also widespread about 300 million people are affected every year, and a much greater number are at risk of these deficiencies. Malnutrition increases people's vulnerability to infections, causing numerous deaths (see also Chapter 8). In the face of this bleak situation, major efforts are required by national governments and the international community to bring about reductions in malnutrition and micronutrient deficiencies.

Food diversification for stable access and a sustainable food supply

Increased food production and access are crucial to achieving major nutritional improvement. More foods should be produced that are rich in all the essential micronutrients, available in sufficient quantities and accessible to people all year round. This requires the collaboration of people working in agriculture, fishery, forestry, small animal husbandry, industry, marketing, communications, women's participation, home economics and nutrition. The wide application of proven technologies and approaches in these fields, as well as the development of new concepts, will contribute towards solving nutritional problems. The results of research must be transmitted to farmers, and efforts must be made to build on farmers' indigenous knowledge. Consumers, too, need to be involved and educated on how to prevent nutritional deficiencies.

Access to stable and sustainable food supplies is a precondition for the establishment of food security at the household level. Greater and more sustained yields from the farming system will increase the potential access of the household to an adequate diet. Similarly, farming practices that improve the regular flow of a variety of different foods into the household throughout the seasons enhance food security for its members. Promoting appropriate and improved technologies for home preservation and drying of vegetables and fruits at home will reduce wastage and ensure better utilization of fresh produce (e.g. mangoes) available in abundance during the harvest season. Increased food processing through the establishment and strengthening of small-scale agro-industries can contribute to the year-round availability and variety of micronutrient-rich foods in rural and urban markets. Agro-processing industries will not only even out seasonal price fluctuations, but will also create jobs and incomes from such activities as processing, storage, distribution and marketing. Agro-processing will also stimulate demand for farmers' crops and products and give consumers additional choice.

Strategies for food and dietary diversification at the community and household levels include a range of food-based activities that can maximize the availability of adequate amounts and greater variety of nutritious foods. These activities include:

· promotion of mixed cropping and integrated farming systems

· introduction of new crops (such as soybean)

· promotion of underexploited traditional foods and home gardens

· promotion of fishery and forestry products for household consumption

· promotion of improved preservation and storage of fruits and vegetables to reduce waste, post-harvest losses and effects of seasonality

· strengthening of small-scale agro-processing and food industries

· nutrition education to encourage the consumption of a healthy and nutritious diet year round.

Some of these strategies are discussed in this chapter. Diversification must entail management and generation of resources in such a way that all the various measures undertaken collectively work to improve the livelihood of the rural poor.

Mixed cropping

Traditional farming systems already use a diversity of crops in both mixed and relay intercropping as well as integration of crops with livestock and/or aquaculture. Research on cropping patterns and rotations is generating improved methods to ensure greater and more sustained yields. A holistic approach to research on farming systems, combining knowledge of socio-economic constraints and a better understanding of small farmers' conditions, should help in finding solutions.

For small-scale producers, mixed cropping can be associated with potential yield improvements and monetary advantages as well as positive implications for food security, dietary balance and nutrition. Mixed cropping reduces the risk of crop failure. It can also reduce the need for expensive inputs if crop residues from leguminous intercrops, supplemented where appropriate with rock phosphate, are returned to the soil. Mixed and/or rotational cropping offers increased protection from disease and pest damage, thus potentially increasing profitability and income. All of these attributes reduce risk in the food supply system and thus favourably influence food security.

Farming systems based on mixed cropping can extend the harvesting period and help to alleviate seasonal food shortages, thus enhancing the stability of household food access. They can also reduce erosion risks by providing increased soil cover and additional crop residues for use as green manure and mulch. Such characteristics offer gains in sustainability and in stability for the food supply system.

The choice of intercrops usually includes legumes and/or oilseeds such as melon seed, groundnut, soybean or sunflower, together with cereals as the dominant crop. In terms of dietary balance, grain legumes, or pulses, contain more protein than cereals and about ten times as much protein as most roots and tubers (Table 22). More significantly, in composition the proteins in cereals and legumes are complementary to each other.

Proteins are not all equally effective in promoting growth. The quality of a protein is determined by the kind of amino acids it contains and the proportion in which they are present. Good-quality proteins contain all the essential amino acids in proportions capable of promoting growth when they are the only proteins in the diet. Such proteins are known as complete proteins or proteins of high biological value. All animal proteins are complete proteins, and if eaten in adequate amounts they meet all a person's protein needs. Proteins from vegetable sources, such as beans, contain all the essential amino acids, but contain one or more of them in insufficient quantity to meet the needs for growth. Bean proteins are generally rich in lysine, an amino acid often deficient in cereal proteins, and legume proteins are therefore valuable supplements to cereal-based diets. Table 23 shows the amino acid composition and amino acid score of wheat and chickpea (Cicer arietinum), separately and in combination. An optimal protein quality can be obtained by combining wheat and chickpea at a ratio of approximately 2:1.

Table 22 - Comparative energy and protein content of some cereals, tubers, legumes and oilseeds (per 100 g)

Source: FAO/United States Department of Health. Education and Welfare, 1968.

The total protein content of different legumes varies widely, from around 12 percent for some varieties of chickpea to over 35 percent for high-protein cultivars of winged bean (Psophocarpus tetragonolobus) and soybean (Glycine max) (Table 24). Protein content also varies widely among different varieties of the same species. For example, the protein content of pigeon pea (Cajanus cajan) can vary from 13 to 20 percent, depending on the cultivar and the conditions of cultivation.

Table 23 - Essential amino acid content of wheat and chickpea (Cicer arietinum) (mg per g nitrogen in the food)

Source: Siegel and Fawcett, 1976 (quoted in FAO, 1989f).

a Amino acid score = amino acid content in wheat/chickpea mixture - amino acid content in ideal protein (egg) x 100.

Table 24 - Proximate composition of mature, dry winged bean seeds, compared with some commercial dry legume seeds (%)

Source: Vietmeyer, 1975 (quoted in FAO, 1989f).

The diversity of food supplies offered by mixed cropping systems accords well with nutritional security, especially since the young leaves of many grain legumes, such as cowpea, are also utilized as a green vegetable, providing essential minerals such as calcium and iron together with useful amounts of vitamins A and C. Table 25 lists some specific nutrients found in the major plant groups.

Improving mixed cropping technologies through farming systems studies and adaptive research

Farming systems research can contribute to the nutritional wellbeing and food security of households in a number of ways. With its comprehensive, interdisciplinary nature and its aim to improve the viability of small farms, such research is geared towards promoting sustainable livelihoods. It also includes a priority focus on increasing household food production and improving the assets of the farm household.

Farming systems research is directed towards improving the access of farm households to food and income through interventions related to choice of crops and cropping practices, increased use of small livestock, development of labour-saving technologies and improved storage and processing techniques. Thus strategies to encourage food diversification, such as promotion of mixed cropping technologies (including systems integrating crops with livestock and/or aquaculture), should include support for farming systems research and for the efforts of adaptive research planning teams which work directly with farmers in developing locally appropriate systems of integrated farming. Specific emphasis should be given in farming systems research to increasing the micronutrient output of agricultural systems and developing effective storage and preservation techniques for fruits and vegetables that can be employed at the household and community levels.

Table 25 - Specific nutrients found in the major plant groups

Carbohydrates, protein, dietary fibre, a vitamin B complex, a iron, a calcium a

Carbohydrates, protein, some vitamin C

Carbohydrates, protein, dietary fibre, a iron, a calcium, a vitamin B complex a

Vitamin C, vitamin A, iron, calcium, vitamin B complex, dietary fibre

Note: The diets of vulnerable groups may be low in ail these nutrients.

a Particularly high nutrient values are found in the hull.

Support services and advocacy for mixed cropping

Improved agricultural practices for a wider variety of food crops, once disseminated and accepted by the producers, often need support if they are to be widely adopted. For the integration of nutrition objectives into farming systems research, such support may be needed at the policy level. Actors involved in providing support may include government agencies through extension services, together with financial institutions, agricultural banks, farmer groups, fertilizer and seed companies, food industries and other private-sector agencies who may wish to profit from policies for food diversification.

The aim must be to provide timely and appropriate inputs, advice and assistance to farmers and producers to maximize the returns and minimize the risks arising from adoption of new strategies. Development of improved seed, together with advice on cultural practices and required inputs, must generally be accompanied by increased access to low-interest credit and greater security of land tenure to reduce risks in marginal areas. Action will also be required to ensure effective demand and marketing.

Smallholder farmers are profit maximizers and will adopt improved technologies if they are not too risky and are profitable at an early stage in the adoption process. Risk is perceived not only in terms of monetary returns, but also in terms of the stability and sustainability of the household's livelihood, including access to food.

The adoption of strategies to improve the productivity of mixed farming systems, if successful, will create an increased supply of a variety of foods in excess of the immediate demand for food within the producer communities. Therefore, before a food diversification strategy is undertaken, it will be necessary to assess and ensure marketability of excess products. Consumer surveys regarding the promoted crops will be required, together with advocacy and nutrition education to stimulate demand among urban groups, who may have become unfamiliar with some traditional foodstuffs.

The United Nations University Institute for Natural Resources in Africa (UNU/INRA) has commissioned a series of studies in 14 African countries on indigenous food crops and other useful plants, to determine people's knowledge of indigenous crops, the use they make of them and the preparations that are made from them. The aim of the surveys is to provide data for determining the status of, and priorities and strategies for, research and training related to indigenous food crops. Such information would be useful in improving cropping systems utilizing indigenous food crops in planning to enhance sustainability, to reduce risks of crop failure, to diversify production to meet farmers' food needs and to ensure genetic conservation of indigenous African food crops and in promoting improved methods of cultivation, processing and preparation.

In the case of small-grained cereals such as millets and sorghum, improved processing techniques may be necessary to provide products for urban housewives, who have become used to the convenience of rice and of wheat-based baked products such as breads and biscuits. Development of appropriate snack foods based on a wide variety of crops will help provide a market to absorb anticipated surpluses. In addition, widespread dissemination of nutritional information about these products should accompany their marketing.

Many of the foodstuffs produced in diversified farming systems, such as roots and tubers, plantains and bananas, and fruits and leafy vegetables, are highly perishable. As their production is promoted, therefore, transport and marketing facilities need to be enhanced to avoid post-harvest losses, whose high cost is inevitably passed on to the consumer. Agricultural policies favouring diversification should ideally entail a review of all sectors of the food chain from production to consumption, as well as mobilization of support at the national, district and community levels through producer and consumer interest groups.

Gardening for food

In many agricultural communities, people rely on one main staple crop whose seasonality implies a period of food shortage, usually referred to as the lean or the hungry season. Home gardening can often supplement family food supplies during lean periods and can generate added income when other sources of employment and income may be limited, provided enough water is available. Home gardens have mostly been maintained by women, who often water and manure them from domestic wastes and use them to produce early crops such as green maize and the fruits, spices and vegetables needed to prepare relishes.

Home gardens are labour intensive, but as they are usually close to the house, the labour required can be combined with home and child care responsibilities. Children are often responsible for carrying water and for simple maintenance work, and they may also be given a few plants or a small area to tend. Support of home gardening through horticultural training and nutrition education at school, including the establishment and maintenance of a school food production garden, will provide useful training in intensive land management for the next generation.

Home gardening is quickly taking different forms to suit individual lifestyles and work patterns. For example, urban dwellers grow maize in the backyard and quite often in the front garden as well busy traders plant bananas behind their roadside stalls and scatter tomato seeds in damp areas around their compound living area and children bury mango seeds in rubbish heaps and in drains at the side of their houses. Gardening is often rather haphazard and disorganized at this level, with chickens and goats competing for the harvest, but the intention and interest in home gardening are there, waiting to be harnessed.

Unfortunately, home gardens have rarely received official recognition, and families often lack the necessary resources, knowledge and inputs to produce crops as effectively as possible. A survey in Ghana indicated that traditional home garden farming systems have a number of major constraints which need to be removed if the systems are to be successfully promoted (Asare, Oppong and Twum-Ampofo, 1985). Important factors to consider in encouraging the expansion of home gardens include security of land tenure to facilitate long-term investment in home gardens and better extension services, including credit, to promote the wider establishment of home gardens and improve their management.

Home gardens and nutrition

Traditional home gardens continue to be important sources of micronutrients for rural communities. Poor people obtain most of their nutrients from food plants, which are cheaper and more accessible than animal foods. In humid tropical countries, green leafy plants such as Amaranthus s pp., Corchorus spp., Bidens pilosa, Gynandropsis spp., Celosia spp., Basella spp., Solanum scabrum, Solanum americanum, Hibiscus sabdariffa and Vigna unguiculata often grow wild and spontaneously. Traditionally, they have been consumed as leafy vegetables when climatic conditions have made the cultivation of exotic vegetables more difficult. The leaves of these plants tend to be good sources of protein, phosphorus and iron as well as vitamins A and C and in some cases B-group vitamins. In many cases they are of higher overall food value than introduced vegetable species, for example cabbage or tomatoes. Table 26 shows the nutritional content of some green leafy vegetables widely used in Africa.

Through careful selection, a range of fruit and vegetable crops can be cultivated throughout the year to provide a constant supply of micronutrients (see Figure 19). For example, yellow and orange perennial fruits (e.g. mango, papaya, cape gooseberry and guava), fruit vegetables (e.g. tomato, pumpkin, squash, gourd and eggplant), some root vegetables (e.g. carrot and yellow-fleshed sweet potato) and most dark-green leafy vegetables are generally moderate to good sources of vitamins A and C. Also, some leaves and fruits produced by local indigenous trees are consumed in rural areas and are rich in micronutrients, e.g. guavas and loquats. Some sources of nutrition from the home garden are given in Table 27.

Some staple foods also have a role as sources of micronutrients. For instance, leaves of roots and tubers are valuable sources. In many countries of the African humid tropics, leaves of cassava (Manihot esculenta) are also consumed. Millets are rich sources of iron in comparison with other cereals such as wheat or maize.

Fruit and vegetable cultivation presents rather different challenges under low-temperature conditions such as those found in the remote highlands of Ethiopia or Lesotho. In such areas, efforts to extend the production of leafy vegetables into the winter season, for example, need to be based on the selection of cold-tolerant cultivars of Brassica crops such as kale and mustard. Alternatively, it might be advisable to adopt locally appropriate protected cultivation practices, such as the use of simple low plastic tunnels or hotbeds which accumulate solar heat and shield crop plants from exposure to extremely low temperature and wind.

Table 26 - Nutritional content of some green leafy vegetables (per 100 g edible portion)

Baobab leaves (Adansonia digitata)

Bitter feat (Vernonia amygdalina)

Cassava leaf (Manihot esculenta)

Cat's whiskers (Cleome gynandra)

Sweet potato (Ipomoea batatas)

Leaves, cooked, plus groundnuts

FIGURE 19 - Food availability from home food production and supply systems, Nchelenge, Zambia

Source: Adapted from Thuvesson, 1988.

Table 27 - Some sources of nutrition from the home garden

Source: Adapted from WHO/UNICEF, 1985.

For fruit and vegetable crops, staggering planting dates in the case of short-cycle crops and choosing a mixture of early maturing, average and late-maturing varieties for both annual and perennial crops can extend the harvest period. For instance, some varieties of mango tree can be harvested three times a year, with flowering, first budding, ripening and harvesting stages occurring simultaneously on different parts of the same tree. Thus the problem of seasonality of available nutrients, in this case primarily beta-carotene, can be overcome.

Role of women in home gardening

The role of women in home and community gardens is of special importance. In addition to being responsible for producing crops on small plots of land, women, especially those who are elderly, often have good knowledge of indigenous species of green leafy vegetables they know how to prepare them and how to preserve both seeds and produce. In local markets, the main vendors of these crops (fresh or dried) are often women.

Extension services unfortunately tend to focus on the major field crops. Improved planting materials, better cultivars and advice on cultural practices are rarely offered to cultivators of home gardens. Since women do the bulk of the work and are more conscious of and concerned with the nutritional needs of the family, extension advice, credit and agricultural inputs should be provided to them for maximum benefits. The organization of women's groups should be promoted to facilitate their access to inputs, to improve the efficiency of their work and thus to improve the diversity and productivity of gardens.

Home gardening as a development strategy

It is important to distinguish between traditional gardens, which are cultivated independently of any intervention, and promoted gardens, which receive external assistance. Many gardening projects, especially those that promote home gardening for nutritional and income-generating benefits, are supported by external donors and non-governmental organizations (NGOs). The involvement of ministries of agriculture has generally been limited, as horticulture is still given a low priority in overall agricultural development programmes, and home gardening, in spite of its potential output, receives even less attention. Consequently, few agricultural extensionists have been trained in gardening techniques, and even fewer in mixed tropical gardening. Still fewer have the knowledge to promote better diets and nutritional practices.

The neglect of gardening in development strategies is partly explained by the paucity of data on the output of traditional home gardening systems expressed in quantitative and monetary-equivalent terms which could demonstrate a significant contribution to economic output and national development. As a result, most agricultural and research programmes tend to underestimate or discount the actual or potential importance of home gardening as a food security strategy, and in particular as a strategy for meeting micronutrient needs.

However, as more evidence showing the social, economic and nutritional benefits of home gardening is becoming available, some governments and the private sector are showing renewed interest in gardening activities. Case-studies from Bangladesh and Central America that examined the socio-economic aspects of home gardening and its contribution to family consumption and income provide strong evidence that home gardening has significant economic benefits and that it can be a viable strategy for increasing food supplies for family consumption (Marsh, 1994).

In an integrated nutrition/home gardening programme supported by Helen Keller International in Bangladesh, overall vegetable consumption increased by 30 percent, with home gardens supplying 80 percent of vegetables consumed by the family. As most of the income earned from sale of home garden produce was spent on food, the prevalence of malnutrition among children of participating families was also reduced. In a study in Honduras and Nicaragua, the gardens supplied a significant proportion of fruits and vegetables, legumes, roots and tubers, coffee, tea and medicinal plants for home consumption. The combined benefits of home consumption, income earned from sale of garden produce (25 percent of total average income in Bangladesh, although wide variation was recorded in Honduras and Nicaragua) and savings in expenditure on garden produce were judged to make a significant contribution to the household economy.

Data from an FAO-supported project in the Niger promoting the production and consumption of vitamin A-rich foods among women's groups and their families showed that the proportion of healthy children increased in the project areas, in comparison with the non-project villages (IVACG, 1994). The successful ingredients of this project were: a strong emphasis on nutrition education to promote underutilized indigenous foods such as green leaves the cultivation of traditional wild sources of vitamin A and the use of food preservation and solar drying to address the problem of seasonal shortages.

Available evidence clearly suggests that home gardening can result in tangible benefits for the household, including food on the table, extra income and healthy children. Access to home-grown fruits, vegetables, small animals and/or fish ensures a more balanced diet for rural families with limited purchasing power and increases their self-reliance. The sale of surpluses can provide direct benefits to producers, especially women farmers, and can also benefit consumers by increasing the quantity and diversity of food supplies in local markets. In communities where specific nutritional deficiencies persist or where there appear to be unexploited possibilities for income generation, households can with some support from government services or NGOs improve the diversity and productivity of their traditional gardens. Home gardening can also be a potentially important element in urban food security strategies.

For home garden projects to be successful and sustainable, a number of important elements need to be considered. Since home gardening is a complex and varied production system forming part of a wider household economy, garden interventions to improve nutrition require a good understanding of local conditions so that project goals can be adapted locally. Thus it is necessary to work closely with local farmers, especially with women farmers, to identify resource and other constraints and locally appropriate ways to promote home gardens that are sustainable. To ensure that availability of garden foods translates into nutritional benefits for the whole family, nutrition education and information about nutritional value and utilization of fruits and vegetables in the diet are essential. Promotion of crop diversification requires flexibility regarding choice of species and cropping patterns, encouragement of diversity and cultivation of locally adapted varieties to enhance nutritional value, and attention to soil fertility, pest management, income-earning potential and genetic conservation. Involving women in all aspects of garden management and nutrition training is crucial, as women do most of the work and are responsible for family nutrition. Regular monitoring of garden progress, although costly, could help to resolve problems and to provide information quantifying gardening output and consumption increases it could thus contribute towards inducing policy-makers and planners to direct more investment to the improvement of the home-gardening sector's output. Community organizing for gardening, preferably building on local farmers' and women's organizations, is also a clear prerequisite for sustainability of gardens in the long term.

Urban agriculture

In urban areas the households most at risk of food insecurity and chronic malnutrition belong to the lowest-income groups which cannot afford to purchase adequate food. Many of these households comprise families of recent migrants who have failed to find regular employment. Their income levels are often so low that they can afford to purchase only the cheapest and most basic foods, and since they cannot afford to rent housing they are forced to camp in makeshift shanty towns on the periphery of cities. Such families often cultivate tiny plots of land within their household area and keep small livestock as a basic survival strategy. However, many of the better-established urban residents have also developed their own subsidiary food supply systems which support food purchase from the urban markets.

Urban agriculture, like the street food trade, often tends to be discounted and frowned upon in official circles as a limited, transitory phenomenon practiced only by recent migrants, living in squatter areas, who have not yet adapted to a market economy. In contradiction to this view, a survey covering cities in a number of countries including Ethiopia, Kenya, Senegal, the United Republic of Tanzania and Uganda (IDRC, 1993) showed that urban agriculture makes a significant contribution to the food supplies of many major cities. A Zambian survey showed that urban enterprises can improve household food security, the variety of the diet and intakes of essential micronutrients (see Box 19 and Tables 28 and 29).

Peri-urban commercial cultivation of high-value crops, including tomatoes, onions, green vegetables and fruit, is a growing food supply enterprise for a number of African cities. Such production systems can be very profitable, justifying their high costs in terms of inputs such as irrigation, fertilizers and pesticides. The proximity of production to urban markets is essential to ensure the freshness of such perishable commodities and their contribution of vitamins and minerals to urban diets.

By practicing a diversified form of urban agriculture, poor urban workers are able to meet some of their nutritional requirements, especially those for minerals and vitamins, through the consumption of some of their produce. This capability is important, as marketed vegetables and fruits often tend to be too expensive for low-income urban dwellers. To encourage urban food gardening as a viable food security strategy, assistance is needed in many instances to provide better access to land, water, seeds, community-based extension services, nutrition education and markets.

Box 19 - Survey of urban agriculture in Lusaka, Zambia

Surveys were carried out in low-income areas of Lusaka, which are made up of five types of settlement: two types of squatter areas (A and B), one of which (A) lacks even basic services two types of serviced plots (C and D), one provided by the local authorities (C), and the other provided under a World Bank housing plan (D) and an area of official low-cost public housing (E).

The questionnaire was designed to provide information about the following types of urban cultivation:

· irrigated plot gardens in the back andlor front yard which are cultivated all the year round

· rainy-season gardens, which are usually located on the periphery of the city, i.e. a type of urban allotment, dependent entirely on rain-fed production.

Analysis showed that nearly 60 percent of the low-income households cultivated one or both types of garden (Table 28). The variety of produce from both types of garden is shown in Table 29.

Source: Adapted from Sanyal, 1985.

Table 28 - Extent of urban agriculture in Lusaka, Zambia (percentage of households engaged)


Chapter 5 - Promotion of food and dietary diversification strategies to enhance and sustain household food security

Many people lack adequate amounts of foods that are rich in the nutrients needed for health and a productive life. Chronic undernutrition affects some 215 million people in sub-Saharan Africa, or 43 percent of the population (FAO, 1996b). Deficiencies of iron, vitamin A and iodine are also widespread about 300 million people are affected every year, and a much greater number are at risk of these deficiencies. Malnutrition increases people's vulnerability to infections, causing numerous deaths (see also Chapter 8). In the face of this bleak situation, major efforts are required by national governments and the international community to bring about reductions in malnutrition and micronutrient deficiencies.

Food diversification for stable access and a sustainable food supply

Increased food production and access are crucial to achieving major nutritional improvement. More foods should be produced that are rich in all the essential micronutrients, available in sufficient quantities and accessible to people all year round. This requires the collaboration of people working in agriculture, fishery, forestry, small animal husbandry, industry, marketing, communications, women's participation, home economics and nutrition. The wide application of proven technologies and approaches in these fields, as well as the development of new concepts, will contribute towards solving nutritional problems. The results of research must be transmitted to farmers, and efforts must be made to build on farmers' indigenous knowledge. Consumers, too, need to be involved and educated on how to prevent nutritional deficiencies.

Access to stable and sustainable food supplies is a precondition for the establishment of food security at the household level. Greater and more sustained yields from the farming system will increase the potential access of the household to an adequate diet. Similarly, farming practices that improve the regular flow of a variety of different foods into the household throughout the seasons enhance food security for its members. Promoting appropriate and improved technologies for home preservation and drying of vegetables and fruits at home will reduce wastage and ensure better utilization of fresh produce (e.g. mangoes) available in abundance during the harvest season. Increased food processing through the establishment and strengthening of small-scale agro-industries can contribute to the year-round availability and variety of micronutrient-rich foods in rural and urban markets. Agro-processing industries will not only even out seasonal price fluctuations, but will also create jobs and incomes from such activities as processing, storage, distribution and marketing. Agro-processing will also stimulate demand for farmers' crops and products and give consumers additional choice.

Strategies for food and dietary diversification at the community and household levels include a range of food-based activities that can maximize the availability of adequate amounts and greater variety of nutritious foods. These activities include:

· promotion of mixed cropping and integrated farming systems

· introduction of new crops (such as soybean)

· promotion of underexploited traditional foods and home gardens

· promotion of fishery and forestry products for household consumption

· promotion of improved preservation and storage of fruits and vegetables to reduce waste, post-harvest losses and effects of seasonality

· strengthening of small-scale agro-processing and food industries

· nutrition education to encourage the consumption of a healthy and nutritious diet year round.

Some of these strategies are discussed in this chapter. Diversification must entail management and generation of resources in such a way that all the various measures undertaken collectively work to improve the livelihood of the rural poor.

Mixed cropping

Traditional farming systems already use a diversity of crops in both mixed and relay intercropping as well as integration of crops with livestock and/or aquaculture. Research on cropping patterns and rotations is generating improved methods to ensure greater and more sustained yields. A holistic approach to research on farming systems, combining knowledge of socio-economic constraints and a better understanding of small farmers' conditions, should help in finding solutions.

For small-scale producers, mixed cropping can be associated with potential yield improvements and monetary advantages as well as positive implications for food security, dietary balance and nutrition. Mixed cropping reduces the risk of crop failure. It can also reduce the need for expensive inputs if crop residues from leguminous intercrops, supplemented where appropriate with rock phosphate, are returned to the soil. Mixed and/or rotational cropping offers increased protection from disease and pest damage, thus potentially increasing profitability and income. All of these attributes reduce risk in the food supply system and thus favourably influence food security.

Farming systems based on mixed cropping can extend the harvesting period and help to alleviate seasonal food shortages, thus enhancing the stability of household food access. They can also reduce erosion risks by providing increased soil cover and additional crop residues for use as green manure and mulch. Such characteristics offer gains in sustainability and in stability for the food supply system.

The choice of intercrops usually includes legumes and/or oilseeds such as melon seed, groundnut, soybean or sunflower, together with cereals as the dominant crop. In terms of dietary balance, grain legumes, or pulses, contain more protein than cereals and about ten times as much protein as most roots and tubers (Table 22). More significantly, in composition the proteins in cereals and legumes are complementary to each other.

Proteins are not all equally effective in promoting growth. The quality of a protein is determined by the kind of amino acids it contains and the proportion in which they are present. Good-quality proteins contain all the essential amino acids in proportions capable of promoting growth when they are the only proteins in the diet. Such proteins are known as complete proteins or proteins of high biological value. All animal proteins are complete proteins, and if eaten in adequate amounts they meet all a person's protein needs. Proteins from vegetable sources, such as beans, contain all the essential amino acids, but contain one or more of them in insufficient quantity to meet the needs for growth. Bean proteins are generally rich in lysine, an amino acid often deficient in cereal proteins, and legume proteins are therefore valuable supplements to cereal-based diets. Table 23 shows the amino acid composition and amino acid score of wheat and chickpea (Cicer arietinum), separately and in combination. An optimal protein quality can be obtained by combining wheat and chickpea at a ratio of approximately 2:1.

Table 22 - Comparative energy and protein content of some cereals, tubers, legumes and oilseeds (per 100 g)

Source: FAO/United States Department of Health. Education and Welfare, 1968.

The total protein content of different legumes varies widely, from around 12 percent for some varieties of chickpea to over 35 percent for high-protein cultivars of winged bean (Psophocarpus tetragonolobus) and soybean (Glycine max) (Table 24). Protein content also varies widely among different varieties of the same species. For example, the protein content of pigeon pea (Cajanus cajan) can vary from 13 to 20 percent, depending on the cultivar and the conditions of cultivation.

Table 23 - Essential amino acid content of wheat and chickpea (Cicer arietinum) (mg per g nitrogen in the food)

Source: Siegel and Fawcett, 1976 (quoted in FAO, 1989f).

a Amino acid score = amino acid content in wheat/chickpea mixture - amino acid content in ideal protein (egg) x 100.

Table 24 - Proximate composition of mature, dry winged bean seeds, compared with some commercial dry legume seeds (%)

Source: Vietmeyer, 1975 (quoted in FAO, 1989f).

The diversity of food supplies offered by mixed cropping systems accords well with nutritional security, especially since the young leaves of many grain legumes, such as cowpea, are also utilized as a green vegetable, providing essential minerals such as calcium and iron together with useful amounts of vitamins A and C. Table 25 lists some specific nutrients found in the major plant groups.

Improving mixed cropping technologies through farming systems studies and adaptive research

Farming systems research can contribute to the nutritional wellbeing and food security of households in a number of ways. With its comprehensive, interdisciplinary nature and its aim to improve the viability of small farms, such research is geared towards promoting sustainable livelihoods. It also includes a priority focus on increasing household food production and improving the assets of the farm household.

Farming systems research is directed towards improving the access of farm households to food and income through interventions related to choice of crops and cropping practices, increased use of small livestock, development of labour-saving technologies and improved storage and processing techniques. Thus strategies to encourage food diversification, such as promotion of mixed cropping technologies (including systems integrating crops with livestock and/or aquaculture), should include support for farming systems research and for the efforts of adaptive research planning teams which work directly with farmers in developing locally appropriate systems of integrated farming. Specific emphasis should be given in farming systems research to increasing the micronutrient output of agricultural systems and developing effective storage and preservation techniques for fruits and vegetables that can be employed at the household and community levels.

Table 25 - Specific nutrients found in the major plant groups

Carbohydrates, protein, dietary fibre, a vitamin B complex, a iron, a calcium a

Carbohydrates, protein, some vitamin C

Carbohydrates, protein, dietary fibre, a iron, a calcium, a vitamin B complex a

Vitamin C, vitamin A, iron, calcium, vitamin B complex, dietary fibre

Note: The diets of vulnerable groups may be low in ail these nutrients.

a Particularly high nutrient values are found in the hull.

Support services and advocacy for mixed cropping

Improved agricultural practices for a wider variety of food crops, once disseminated and accepted by the producers, often need support if they are to be widely adopted. For the integration of nutrition objectives into farming systems research, such support may be needed at the policy level. Actors involved in providing support may include government agencies through extension services, together with financial institutions, agricultural banks, farmer groups, fertilizer and seed companies, food industries and other private-sector agencies who may wish to profit from policies for food diversification.

The aim must be to provide timely and appropriate inputs, advice and assistance to farmers and producers to maximize the returns and minimize the risks arising from adoption of new strategies. Development of improved seed, together with advice on cultural practices and required inputs, must generally be accompanied by increased access to low-interest credit and greater security of land tenure to reduce risks in marginal areas. Action will also be required to ensure effective demand and marketing.

Smallholder farmers are profit maximizers and will adopt improved technologies if they are not too risky and are profitable at an early stage in the adoption process. Risk is perceived not only in terms of monetary returns, but also in terms of the stability and sustainability of the household's livelihood, including access to food.

The adoption of strategies to improve the productivity of mixed farming systems, if successful, will create an increased supply of a variety of foods in excess of the immediate demand for food within the producer communities. Therefore, before a food diversification strategy is undertaken, it will be necessary to assess and ensure marketability of excess products. Consumer surveys regarding the promoted crops will be required, together with advocacy and nutrition education to stimulate demand among urban groups, who may have become unfamiliar with some traditional foodstuffs.

The United Nations University Institute for Natural Resources in Africa (UNU/INRA) has commissioned a series of studies in 14 African countries on indigenous food crops and other useful plants, to determine people's knowledge of indigenous crops, the use they make of them and the preparations that are made from them. The aim of the surveys is to provide data for determining the status of, and priorities and strategies for, research and training related to indigenous food crops. Such information would be useful in improving cropping systems utilizing indigenous food crops in planning to enhance sustainability, to reduce risks of crop failure, to diversify production to meet farmers' food needs and to ensure genetic conservation of indigenous African food crops and in promoting improved methods of cultivation, processing and preparation.

In the case of small-grained cereals such as millets and sorghum, improved processing techniques may be necessary to provide products for urban housewives, who have become used to the convenience of rice and of wheat-based baked products such as breads and biscuits. Development of appropriate snack foods based on a wide variety of crops will help provide a market to absorb anticipated surpluses. In addition, widespread dissemination of nutritional information about these products should accompany their marketing.

Many of the foodstuffs produced in diversified farming systems, such as roots and tubers, plantains and bananas, and fruits and leafy vegetables, are highly perishable. As their production is promoted, therefore, transport and marketing facilities need to be enhanced to avoid post-harvest losses, whose high cost is inevitably passed on to the consumer. Agricultural policies favouring diversification should ideally entail a review of all sectors of the food chain from production to consumption, as well as mobilization of support at the national, district and community levels through producer and consumer interest groups.

Gardening for food

In many agricultural communities, people rely on one main staple crop whose seasonality implies a period of food shortage, usually referred to as the lean or the hungry season. Home gardening can often supplement family food supplies during lean periods and can generate added income when other sources of employment and income may be limited, provided enough water is available. Home gardens have mostly been maintained by women, who often water and manure them from domestic wastes and use them to produce early crops such as green maize and the fruits, spices and vegetables needed to prepare relishes.

Home gardens are labour intensive, but as they are usually close to the house, the labour required can be combined with home and child care responsibilities. Children are often responsible for carrying water and for simple maintenance work, and they may also be given a few plants or a small area to tend. Support of home gardening through horticultural training and nutrition education at school, including the establishment and maintenance of a school food production garden, will provide useful training in intensive land management for the next generation.

Home gardening is quickly taking different forms to suit individual lifestyles and work patterns. For example, urban dwellers grow maize in the backyard and quite often in the front garden as well busy traders plant bananas behind their roadside stalls and scatter tomato seeds in damp areas around their compound living area and children bury mango seeds in rubbish heaps and in drains at the side of their houses. Gardening is often rather haphazard and disorganized at this level, with chickens and goats competing for the harvest, but the intention and interest in home gardening are there, waiting to be harnessed.

Unfortunately, home gardens have rarely received official recognition, and families often lack the necessary resources, knowledge and inputs to produce crops as effectively as possible. A survey in Ghana indicated that traditional home garden farming systems have a number of major constraints which need to be removed if the systems are to be successfully promoted (Asare, Oppong and Twum-Ampofo, 1985). Important factors to consider in encouraging the expansion of home gardens include security of land tenure to facilitate long-term investment in home gardens and better extension services, including credit, to promote the wider establishment of home gardens and improve their management.

Home gardens and nutrition

Traditional home gardens continue to be important sources of micronutrients for rural communities. Poor people obtain most of their nutrients from food plants, which are cheaper and more accessible than animal foods. In humid tropical countries, green leafy plants such as Amaranthus s pp., Corchorus spp., Bidens pilosa, Gynandropsis spp., Celosia spp., Basella spp., Solanum scabrum, Solanum americanum, Hibiscus sabdariffa and Vigna unguiculata often grow wild and spontaneously. Traditionally, they have been consumed as leafy vegetables when climatic conditions have made the cultivation of exotic vegetables more difficult. The leaves of these plants tend to be good sources of protein, phosphorus and iron as well as vitamins A and C and in some cases B-group vitamins. In many cases they are of higher overall food value than introduced vegetable species, for example cabbage or tomatoes. Table 26 shows the nutritional content of some green leafy vegetables widely used in Africa.

Through careful selection, a range of fruit and vegetable crops can be cultivated throughout the year to provide a constant supply of micronutrients (see Figure 19). For example, yellow and orange perennial fruits (e.g. mango, papaya, cape gooseberry and guava), fruit vegetables (e.g. tomato, pumpkin, squash, gourd and eggplant), some root vegetables (e.g. carrot and yellow-fleshed sweet potato) and most dark-green leafy vegetables are generally moderate to good sources of vitamins A and C. Also, some leaves and fruits produced by local indigenous trees are consumed in rural areas and are rich in micronutrients, e.g. guavas and loquats. Some sources of nutrition from the home garden are given in Table 27.

Some staple foods also have a role as sources of micronutrients. For instance, leaves of roots and tubers are valuable sources. In many countries of the African humid tropics, leaves of cassava (Manihot esculenta) are also consumed. Millets are rich sources of iron in comparison with other cereals such as wheat or maize.

Fruit and vegetable cultivation presents rather different challenges under low-temperature conditions such as those found in the remote highlands of Ethiopia or Lesotho. In such areas, efforts to extend the production of leafy vegetables into the winter season, for example, need to be based on the selection of cold-tolerant cultivars of Brassica crops such as kale and mustard. Alternatively, it might be advisable to adopt locally appropriate protected cultivation practices, such as the use of simple low plastic tunnels or hotbeds which accumulate solar heat and shield crop plants from exposure to extremely low temperature and wind.

Table 26 - Nutritional content of some green leafy vegetables (per 100 g edible portion)

Baobab leaves (Adansonia digitata)

Bitter feat (Vernonia amygdalina)

Cassava leaf (Manihot esculenta)

Cat's whiskers (Cleome gynandra)

Sweet potato (Ipomoea batatas)

Leaves, cooked, plus groundnuts

FIGURE 19 - Food availability from home food production and supply systems, Nchelenge, Zambia

Source: Adapted from Thuvesson, 1988.

Table 27 - Some sources of nutrition from the home garden

Source: Adapted from WHO/UNICEF, 1985.

For fruit and vegetable crops, staggering planting dates in the case of short-cycle crops and choosing a mixture of early maturing, average and late-maturing varieties for both annual and perennial crops can extend the harvest period. For instance, some varieties of mango tree can be harvested three times a year, with flowering, first budding, ripening and harvesting stages occurring simultaneously on different parts of the same tree. Thus the problem of seasonality of available nutrients, in this case primarily beta-carotene, can be overcome.

Role of women in home gardening

The role of women in home and community gardens is of special importance. In addition to being responsible for producing crops on small plots of land, women, especially those who are elderly, often have good knowledge of indigenous species of green leafy vegetables they know how to prepare them and how to preserve both seeds and produce. In local markets, the main vendors of these crops (fresh or dried) are often women.

Extension services unfortunately tend to focus on the major field crops. Improved planting materials, better cultivars and advice on cultural practices are rarely offered to cultivators of home gardens. Since women do the bulk of the work and are more conscious of and concerned with the nutritional needs of the family, extension advice, credit and agricultural inputs should be provided to them for maximum benefits. The organization of women's groups should be promoted to facilitate their access to inputs, to improve the efficiency of their work and thus to improve the diversity and productivity of gardens.

Home gardening as a development strategy

It is important to distinguish between traditional gardens, which are cultivated independently of any intervention, and promoted gardens, which receive external assistance. Many gardening projects, especially those that promote home gardening for nutritional and income-generating benefits, are supported by external donors and non-governmental organizations (NGOs). The involvement of ministries of agriculture has generally been limited, as horticulture is still given a low priority in overall agricultural development programmes, and home gardening, in spite of its potential output, receives even less attention. Consequently, few agricultural extensionists have been trained in gardening techniques, and even fewer in mixed tropical gardening. Still fewer have the knowledge to promote better diets and nutritional practices.

The neglect of gardening in development strategies is partly explained by the paucity of data on the output of traditional home gardening systems expressed in quantitative and monetary-equivalent terms which could demonstrate a significant contribution to economic output and national development. As a result, most agricultural and research programmes tend to underestimate or discount the actual or potential importance of home gardening as a food security strategy, and in particular as a strategy for meeting micronutrient needs.

However, as more evidence showing the social, economic and nutritional benefits of home gardening is becoming available, some governments and the private sector are showing renewed interest in gardening activities. Case-studies from Bangladesh and Central America that examined the socio-economic aspects of home gardening and its contribution to family consumption and income provide strong evidence that home gardening has significant economic benefits and that it can be a viable strategy for increasing food supplies for family consumption (Marsh, 1994).

In an integrated nutrition/home gardening programme supported by Helen Keller International in Bangladesh, overall vegetable consumption increased by 30 percent, with home gardens supplying 80 percent of vegetables consumed by the family. As most of the income earned from sale of home garden produce was spent on food, the prevalence of malnutrition among children of participating families was also reduced. In a study in Honduras and Nicaragua, the gardens supplied a significant proportion of fruits and vegetables, legumes, roots and tubers, coffee, tea and medicinal plants for home consumption. The combined benefits of home consumption, income earned from sale of garden produce (25 percent of total average income in Bangladesh, although wide variation was recorded in Honduras and Nicaragua) and savings in expenditure on garden produce were judged to make a significant contribution to the household economy.

Data from an FAO-supported project in the Niger promoting the production and consumption of vitamin A-rich foods among women's groups and their families showed that the proportion of healthy children increased in the project areas, in comparison with the non-project villages (IVACG, 1994). The successful ingredients of this project were: a strong emphasis on nutrition education to promote underutilized indigenous foods such as green leaves the cultivation of traditional wild sources of vitamin A and the use of food preservation and solar drying to address the problem of seasonal shortages.

Available evidence clearly suggests that home gardening can result in tangible benefits for the household, including food on the table, extra income and healthy children. Access to home-grown fruits, vegetables, small animals and/or fish ensures a more balanced diet for rural families with limited purchasing power and increases their self-reliance. The sale of surpluses can provide direct benefits to producers, especially women farmers, and can also benefit consumers by increasing the quantity and diversity of food supplies in local markets. In communities where specific nutritional deficiencies persist or where there appear to be unexploited possibilities for income generation, households can with some support from government services or NGOs improve the diversity and productivity of their traditional gardens. Home gardening can also be a potentially important element in urban food security strategies.

For home garden projects to be successful and sustainable, a number of important elements need to be considered. Since home gardening is a complex and varied production system forming part of a wider household economy, garden interventions to improve nutrition require a good understanding of local conditions so that project goals can be adapted locally. Thus it is necessary to work closely with local farmers, especially with women farmers, to identify resource and other constraints and locally appropriate ways to promote home gardens that are sustainable. To ensure that availability of garden foods translates into nutritional benefits for the whole family, nutrition education and information about nutritional value and utilization of fruits and vegetables in the diet are essential. Promotion of crop diversification requires flexibility regarding choice of species and cropping patterns, encouragement of diversity and cultivation of locally adapted varieties to enhance nutritional value, and attention to soil fertility, pest management, income-earning potential and genetic conservation. Involving women in all aspects of garden management and nutrition training is crucial, as women do most of the work and are responsible for family nutrition. Regular monitoring of garden progress, although costly, could help to resolve problems and to provide information quantifying gardening output and consumption increases it could thus contribute towards inducing policy-makers and planners to direct more investment to the improvement of the home-gardening sector's output. Community organizing for gardening, preferably building on local farmers' and women's organizations, is also a clear prerequisite for sustainability of gardens in the long term.

Urban agriculture

In urban areas the households most at risk of food insecurity and chronic malnutrition belong to the lowest-income groups which cannot afford to purchase adequate food. Many of these households comprise families of recent migrants who have failed to find regular employment. Their income levels are often so low that they can afford to purchase only the cheapest and most basic foods, and since they cannot afford to rent housing they are forced to camp in makeshift shanty towns on the periphery of cities. Such families often cultivate tiny plots of land within their household area and keep small livestock as a basic survival strategy. However, many of the better-established urban residents have also developed their own subsidiary food supply systems which support food purchase from the urban markets.

Urban agriculture, like the street food trade, often tends to be discounted and frowned upon in official circles as a limited, transitory phenomenon practiced only by recent migrants, living in squatter areas, who have not yet adapted to a market economy. In contradiction to this view, a survey covering cities in a number of countries including Ethiopia, Kenya, Senegal, the United Republic of Tanzania and Uganda (IDRC, 1993) showed that urban agriculture makes a significant contribution to the food supplies of many major cities. A Zambian survey showed that urban enterprises can improve household food security, the variety of the diet and intakes of essential micronutrients (see Box 19 and Tables 28 and 29).

Peri-urban commercial cultivation of high-value crops, including tomatoes, onions, green vegetables and fruit, is a growing food supply enterprise for a number of African cities. Such production systems can be very profitable, justifying their high costs in terms of inputs such as irrigation, fertilizers and pesticides. The proximity of production to urban markets is essential to ensure the freshness of such perishable commodities and their contribution of vitamins and minerals to urban diets.

By practicing a diversified form of urban agriculture, poor urban workers are able to meet some of their nutritional requirements, especially those for minerals and vitamins, through the consumption of some of their produce. This capability is important, as marketed vegetables and fruits often tend to be too expensive for low-income urban dwellers. To encourage urban food gardening as a viable food security strategy, assistance is needed in many instances to provide better access to land, water, seeds, community-based extension services, nutrition education and markets.

Box 19 - Survey of urban agriculture in Lusaka, Zambia

Surveys were carried out in low-income areas of Lusaka, which are made up of five types of settlement: two types of squatter areas (A and B), one of which (A) lacks even basic services two types of serviced plots (C and D), one provided by the local authorities (C), and the other provided under a World Bank housing plan (D) and an area of official low-cost public housing (E).

The questionnaire was designed to provide information about the following types of urban cultivation:

· irrigated plot gardens in the back andlor front yard which are cultivated all the year round

· rainy-season gardens, which are usually located on the periphery of the city, i.e. a type of urban allotment, dependent entirely on rain-fed production.

Analysis showed that nearly 60 percent of the low-income households cultivated one or both types of garden (Table 28). The variety of produce from both types of garden is shown in Table 29.

Source: Adapted from Sanyal, 1985.

Table 28 - Extent of urban agriculture in Lusaka, Zambia (percentage of households engaged)


Chapter 5 - Promotion of food and dietary diversification strategies to enhance and sustain household food security

Many people lack adequate amounts of foods that are rich in the nutrients needed for health and a productive life. Chronic undernutrition affects some 215 million people in sub-Saharan Africa, or 43 percent of the population (FAO, 1996b). Deficiencies of iron, vitamin A and iodine are also widespread about 300 million people are affected every year, and a much greater number are at risk of these deficiencies. Malnutrition increases people's vulnerability to infections, causing numerous deaths (see also Chapter 8). In the face of this bleak situation, major efforts are required by national governments and the international community to bring about reductions in malnutrition and micronutrient deficiencies.

Food diversification for stable access and a sustainable food supply

Increased food production and access are crucial to achieving major nutritional improvement. More foods should be produced that are rich in all the essential micronutrients, available in sufficient quantities and accessible to people all year round. This requires the collaboration of people working in agriculture, fishery, forestry, small animal husbandry, industry, marketing, communications, women's participation, home economics and nutrition. The wide application of proven technologies and approaches in these fields, as well as the development of new concepts, will contribute towards solving nutritional problems. The results of research must be transmitted to farmers, and efforts must be made to build on farmers' indigenous knowledge. Consumers, too, need to be involved and educated on how to prevent nutritional deficiencies.

Access to stable and sustainable food supplies is a precondition for the establishment of food security at the household level. Greater and more sustained yields from the farming system will increase the potential access of the household to an adequate diet. Similarly, farming practices that improve the regular flow of a variety of different foods into the household throughout the seasons enhance food security for its members. Promoting appropriate and improved technologies for home preservation and drying of vegetables and fruits at home will reduce wastage and ensure better utilization of fresh produce (e.g. mangoes) available in abundance during the harvest season. Increased food processing through the establishment and strengthening of small-scale agro-industries can contribute to the year-round availability and variety of micronutrient-rich foods in rural and urban markets. Agro-processing industries will not only even out seasonal price fluctuations, but will also create jobs and incomes from such activities as processing, storage, distribution and marketing. Agro-processing will also stimulate demand for farmers' crops and products and give consumers additional choice.

Strategies for food and dietary diversification at the community and household levels include a range of food-based activities that can maximize the availability of adequate amounts and greater variety of nutritious foods. These activities include:

· promotion of mixed cropping and integrated farming systems

· introduction of new crops (such as soybean)

· promotion of underexploited traditional foods and home gardens

· promotion of fishery and forestry products for household consumption

· promotion of improved preservation and storage of fruits and vegetables to reduce waste, post-harvest losses and effects of seasonality

· strengthening of small-scale agro-processing and food industries

· nutrition education to encourage the consumption of a healthy and nutritious diet year round.

Some of these strategies are discussed in this chapter. Diversification must entail management and generation of resources in such a way that all the various measures undertaken collectively work to improve the livelihood of the rural poor.

Mixed cropping

Traditional farming systems already use a diversity of crops in both mixed and relay intercropping as well as integration of crops with livestock and/or aquaculture. Research on cropping patterns and rotations is generating improved methods to ensure greater and more sustained yields. A holistic approach to research on farming systems, combining knowledge of socio-economic constraints and a better understanding of small farmers' conditions, should help in finding solutions.

For small-scale producers, mixed cropping can be associated with potential yield improvements and monetary advantages as well as positive implications for food security, dietary balance and nutrition. Mixed cropping reduces the risk of crop failure. It can also reduce the need for expensive inputs if crop residues from leguminous intercrops, supplemented where appropriate with rock phosphate, are returned to the soil. Mixed and/or rotational cropping offers increased protection from disease and pest damage, thus potentially increasing profitability and income. All of these attributes reduce risk in the food supply system and thus favourably influence food security.

Farming systems based on mixed cropping can extend the harvesting period and help to alleviate seasonal food shortages, thus enhancing the stability of household food access. They can also reduce erosion risks by providing increased soil cover and additional crop residues for use as green manure and mulch. Such characteristics offer gains in sustainability and in stability for the food supply system.

The choice of intercrops usually includes legumes and/or oilseeds such as melon seed, groundnut, soybean or sunflower, together with cereals as the dominant crop. In terms of dietary balance, grain legumes, or pulses, contain more protein than cereals and about ten times as much protein as most roots and tubers (Table 22). More significantly, in composition the proteins in cereals and legumes are complementary to each other.

Proteins are not all equally effective in promoting growth. The quality of a protein is determined by the kind of amino acids it contains and the proportion in which they are present. Good-quality proteins contain all the essential amino acids in proportions capable of promoting growth when they are the only proteins in the diet. Such proteins are known as complete proteins or proteins of high biological value. All animal proteins are complete proteins, and if eaten in adequate amounts they meet all a person's protein needs. Proteins from vegetable sources, such as beans, contain all the essential amino acids, but contain one or more of them in insufficient quantity to meet the needs for growth. Bean proteins are generally rich in lysine, an amino acid often deficient in cereal proteins, and legume proteins are therefore valuable supplements to cereal-based diets. Table 23 shows the amino acid composition and amino acid score of wheat and chickpea (Cicer arietinum), separately and in combination. An optimal protein quality can be obtained by combining wheat and chickpea at a ratio of approximately 2:1.

Table 22 - Comparative energy and protein content of some cereals, tubers, legumes and oilseeds (per 100 g)

Source: FAO/United States Department of Health. Education and Welfare, 1968.

The total protein content of different legumes varies widely, from around 12 percent for some varieties of chickpea to over 35 percent for high-protein cultivars of winged bean (Psophocarpus tetragonolobus) and soybean (Glycine max) (Table 24). Protein content also varies widely among different varieties of the same species. For example, the protein content of pigeon pea (Cajanus cajan) can vary from 13 to 20 percent, depending on the cultivar and the conditions of cultivation.

Table 23 - Essential amino acid content of wheat and chickpea (Cicer arietinum) (mg per g nitrogen in the food)

Source: Siegel and Fawcett, 1976 (quoted in FAO, 1989f).

a Amino acid score = amino acid content in wheat/chickpea mixture - amino acid content in ideal protein (egg) x 100.

Table 24 - Proximate composition of mature, dry winged bean seeds, compared with some commercial dry legume seeds (%)

Source: Vietmeyer, 1975 (quoted in FAO, 1989f).

The diversity of food supplies offered by mixed cropping systems accords well with nutritional security, especially since the young leaves of many grain legumes, such as cowpea, are also utilized as a green vegetable, providing essential minerals such as calcium and iron together with useful amounts of vitamins A and C. Table 25 lists some specific nutrients found in the major plant groups.

Improving mixed cropping technologies through farming systems studies and adaptive research

Farming systems research can contribute to the nutritional wellbeing and food security of households in a number of ways. With its comprehensive, interdisciplinary nature and its aim to improve the viability of small farms, such research is geared towards promoting sustainable livelihoods. It also includes a priority focus on increasing household food production and improving the assets of the farm household.

Farming systems research is directed towards improving the access of farm households to food and income through interventions related to choice of crops and cropping practices, increased use of small livestock, development of labour-saving technologies and improved storage and processing techniques. Thus strategies to encourage food diversification, such as promotion of mixed cropping technologies (including systems integrating crops with livestock and/or aquaculture), should include support for farming systems research and for the efforts of adaptive research planning teams which work directly with farmers in developing locally appropriate systems of integrated farming. Specific emphasis should be given in farming systems research to increasing the micronutrient output of agricultural systems and developing effective storage and preservation techniques for fruits and vegetables that can be employed at the household and community levels.

Table 25 - Specific nutrients found in the major plant groups

Carbohydrates, protein, dietary fibre, a vitamin B complex, a iron, a calcium a

Carbohydrates, protein, some vitamin C

Carbohydrates, protein, dietary fibre, a iron, a calcium, a vitamin B complex a

Vitamin C, vitamin A, iron, calcium, vitamin B complex, dietary fibre

Note: The diets of vulnerable groups may be low in ail these nutrients.

a Particularly high nutrient values are found in the hull.

Support services and advocacy for mixed cropping

Improved agricultural practices for a wider variety of food crops, once disseminated and accepted by the producers, often need support if they are to be widely adopted. For the integration of nutrition objectives into farming systems research, such support may be needed at the policy level. Actors involved in providing support may include government agencies through extension services, together with financial institutions, agricultural banks, farmer groups, fertilizer and seed companies, food industries and other private-sector agencies who may wish to profit from policies for food diversification.

The aim must be to provide timely and appropriate inputs, advice and assistance to farmers and producers to maximize the returns and minimize the risks arising from adoption of new strategies. Development of improved seed, together with advice on cultural practices and required inputs, must generally be accompanied by increased access to low-interest credit and greater security of land tenure to reduce risks in marginal areas. Action will also be required to ensure effective demand and marketing.

Smallholder farmers are profit maximizers and will adopt improved technologies if they are not too risky and are profitable at an early stage in the adoption process. Risk is perceived not only in terms of monetary returns, but also in terms of the stability and sustainability of the household's livelihood, including access to food.

The adoption of strategies to improve the productivity of mixed farming systems, if successful, will create an increased supply of a variety of foods in excess of the immediate demand for food within the producer communities. Therefore, before a food diversification strategy is undertaken, it will be necessary to assess and ensure marketability of excess products. Consumer surveys regarding the promoted crops will be required, together with advocacy and nutrition education to stimulate demand among urban groups, who may have become unfamiliar with some traditional foodstuffs.

The United Nations University Institute for Natural Resources in Africa (UNU/INRA) has commissioned a series of studies in 14 African countries on indigenous food crops and other useful plants, to determine people's knowledge of indigenous crops, the use they make of them and the preparations that are made from them. The aim of the surveys is to provide data for determining the status of, and priorities and strategies for, research and training related to indigenous food crops. Such information would be useful in improving cropping systems utilizing indigenous food crops in planning to enhance sustainability, to reduce risks of crop failure, to diversify production to meet farmers' food needs and to ensure genetic conservation of indigenous African food crops and in promoting improved methods of cultivation, processing and preparation.

In the case of small-grained cereals such as millets and sorghum, improved processing techniques may be necessary to provide products for urban housewives, who have become used to the convenience of rice and of wheat-based baked products such as breads and biscuits. Development of appropriate snack foods based on a wide variety of crops will help provide a market to absorb anticipated surpluses. In addition, widespread dissemination of nutritional information about these products should accompany their marketing.

Many of the foodstuffs produced in diversified farming systems, such as roots and tubers, plantains and bananas, and fruits and leafy vegetables, are highly perishable. As their production is promoted, therefore, transport and marketing facilities need to be enhanced to avoid post-harvest losses, whose high cost is inevitably passed on to the consumer. Agricultural policies favouring diversification should ideally entail a review of all sectors of the food chain from production to consumption, as well as mobilization of support at the national, district and community levels through producer and consumer interest groups.

Gardening for food

In many agricultural communities, people rely on one main staple crop whose seasonality implies a period of food shortage, usually referred to as the lean or the hungry season. Home gardening can often supplement family food supplies during lean periods and can generate added income when other sources of employment and income may be limited, provided enough water is available. Home gardens have mostly been maintained by women, who often water and manure them from domestic wastes and use them to produce early crops such as green maize and the fruits, spices and vegetables needed to prepare relishes.

Home gardens are labour intensive, but as they are usually close to the house, the labour required can be combined with home and child care responsibilities. Children are often responsible for carrying water and for simple maintenance work, and they may also be given a few plants or a small area to tend. Support of home gardening through horticultural training and nutrition education at school, including the establishment and maintenance of a school food production garden, will provide useful training in intensive land management for the next generation.

Home gardening is quickly taking different forms to suit individual lifestyles and work patterns. For example, urban dwellers grow maize in the backyard and quite often in the front garden as well busy traders plant bananas behind their roadside stalls and scatter tomato seeds in damp areas around their compound living area and children bury mango seeds in rubbish heaps and in drains at the side of their houses. Gardening is often rather haphazard and disorganized at this level, with chickens and goats competing for the harvest, but the intention and interest in home gardening are there, waiting to be harnessed.

Unfortunately, home gardens have rarely received official recognition, and families often lack the necessary resources, knowledge and inputs to produce crops as effectively as possible. A survey in Ghana indicated that traditional home garden farming systems have a number of major constraints which need to be removed if the systems are to be successfully promoted (Asare, Oppong and Twum-Ampofo, 1985). Important factors to consider in encouraging the expansion of home gardens include security of land tenure to facilitate long-term investment in home gardens and better extension services, including credit, to promote the wider establishment of home gardens and improve their management.

Home gardens and nutrition

Traditional home gardens continue to be important sources of micronutrients for rural communities. Poor people obtain most of their nutrients from food plants, which are cheaper and more accessible than animal foods. In humid tropical countries, green leafy plants such as Amaranthus s pp., Corchorus spp., Bidens pilosa, Gynandropsis spp., Celosia spp., Basella spp., Solanum scabrum, Solanum americanum, Hibiscus sabdariffa and Vigna unguiculata often grow wild and spontaneously. Traditionally, they have been consumed as leafy vegetables when climatic conditions have made the cultivation of exotic vegetables more difficult. The leaves of these plants tend to be good sources of protein, phosphorus and iron as well as vitamins A and C and in some cases B-group vitamins. In many cases they are of higher overall food value than introduced vegetable species, for example cabbage or tomatoes. Table 26 shows the nutritional content of some green leafy vegetables widely used in Africa.

Through careful selection, a range of fruit and vegetable crops can be cultivated throughout the year to provide a constant supply of micronutrients (see Figure 19). For example, yellow and orange perennial fruits (e.g. mango, papaya, cape gooseberry and guava), fruit vegetables (e.g. tomato, pumpkin, squash, gourd and eggplant), some root vegetables (e.g. carrot and yellow-fleshed sweet potato) and most dark-green leafy vegetables are generally moderate to good sources of vitamins A and C. Also, some leaves and fruits produced by local indigenous trees are consumed in rural areas and are rich in micronutrients, e.g. guavas and loquats. Some sources of nutrition from the home garden are given in Table 27.

Some staple foods also have a role as sources of micronutrients. For instance, leaves of roots and tubers are valuable sources. In many countries of the African humid tropics, leaves of cassava (Manihot esculenta) are also consumed. Millets are rich sources of iron in comparison with other cereals such as wheat or maize.

Fruit and vegetable cultivation presents rather different challenges under low-temperature conditions such as those found in the remote highlands of Ethiopia or Lesotho. In such areas, efforts to extend the production of leafy vegetables into the winter season, for example, need to be based on the selection of cold-tolerant cultivars of Brassica crops such as kale and mustard. Alternatively, it might be advisable to adopt locally appropriate protected cultivation practices, such as the use of simple low plastic tunnels or hotbeds which accumulate solar heat and shield crop plants from exposure to extremely low temperature and wind.

Table 26 - Nutritional content of some green leafy vegetables (per 100 g edible portion)

Baobab leaves (Adansonia digitata)

Bitter feat (Vernonia amygdalina)

Cassava leaf (Manihot esculenta)

Cat's whiskers (Cleome gynandra)

Sweet potato (Ipomoea batatas)

Leaves, cooked, plus groundnuts

FIGURE 19 - Food availability from home food production and supply systems, Nchelenge, Zambia

Source: Adapted from Thuvesson, 1988.

Table 27 - Some sources of nutrition from the home garden

Source: Adapted from WHO/UNICEF, 1985.

For fruit and vegetable crops, staggering planting dates in the case of short-cycle crops and choosing a mixture of early maturing, average and late-maturing varieties for both annual and perennial crops can extend the harvest period. For instance, some varieties of mango tree can be harvested three times a year, with flowering, first budding, ripening and harvesting stages occurring simultaneously on different parts of the same tree. Thus the problem of seasonality of available nutrients, in this case primarily beta-carotene, can be overcome.

Role of women in home gardening

The role of women in home and community gardens is of special importance. In addition to being responsible for producing crops on small plots of land, women, especially those who are elderly, often have good knowledge of indigenous species of green leafy vegetables they know how to prepare them and how to preserve both seeds and produce. In local markets, the main vendors of these crops (fresh or dried) are often women.

Extension services unfortunately tend to focus on the major field crops. Improved planting materials, better cultivars and advice on cultural practices are rarely offered to cultivators of home gardens. Since women do the bulk of the work and are more conscious of and concerned with the nutritional needs of the family, extension advice, credit and agricultural inputs should be provided to them for maximum benefits. The organization of women's groups should be promoted to facilitate their access to inputs, to improve the efficiency of their work and thus to improve the diversity and productivity of gardens.

Home gardening as a development strategy

It is important to distinguish between traditional gardens, which are cultivated independently of any intervention, and promoted gardens, which receive external assistance. Many gardening projects, especially those that promote home gardening for nutritional and income-generating benefits, are supported by external donors and non-governmental organizations (NGOs). The involvement of ministries of agriculture has generally been limited, as horticulture is still given a low priority in overall agricultural development programmes, and home gardening, in spite of its potential output, receives even less attention. Consequently, few agricultural extensionists have been trained in gardening techniques, and even fewer in mixed tropical gardening. Still fewer have the knowledge to promote better diets and nutritional practices.

The neglect of gardening in development strategies is partly explained by the paucity of data on the output of traditional home gardening systems expressed in quantitative and monetary-equivalent terms which could demonstrate a significant contribution to economic output and national development. As a result, most agricultural and research programmes tend to underestimate or discount the actual or potential importance of home gardening as a food security strategy, and in particular as a strategy for meeting micronutrient needs.

However, as more evidence showing the social, economic and nutritional benefits of home gardening is becoming available, some governments and the private sector are showing renewed interest in gardening activities. Case-studies from Bangladesh and Central America that examined the socio-economic aspects of home gardening and its contribution to family consumption and income provide strong evidence that home gardening has significant economic benefits and that it can be a viable strategy for increasing food supplies for family consumption (Marsh, 1994).

In an integrated nutrition/home gardening programme supported by Helen Keller International in Bangladesh, overall vegetable consumption increased by 30 percent, with home gardens supplying 80 percent of vegetables consumed by the family. As most of the income earned from sale of home garden produce was spent on food, the prevalence of malnutrition among children of participating families was also reduced. In a study in Honduras and Nicaragua, the gardens supplied a significant proportion of fruits and vegetables, legumes, roots and tubers, coffee, tea and medicinal plants for home consumption. The combined benefits of home consumption, income earned from sale of garden produce (25 percent of total average income in Bangladesh, although wide variation was recorded in Honduras and Nicaragua) and savings in expenditure on garden produce were judged to make a significant contribution to the household economy.

Data from an FAO-supported project in the Niger promoting the production and consumption of vitamin A-rich foods among women's groups and their families showed that the proportion of healthy children increased in the project areas, in comparison with the non-project villages (IVACG, 1994). The successful ingredients of this project were: a strong emphasis on nutrition education to promote underutilized indigenous foods such as green leaves the cultivation of traditional wild sources of vitamin A and the use of food preservation and solar drying to address the problem of seasonal shortages.

Available evidence clearly suggests that home gardening can result in tangible benefits for the household, including food on the table, extra income and healthy children. Access to home-grown fruits, vegetables, small animals and/or fish ensures a more balanced diet for rural families with limited purchasing power and increases their self-reliance. The sale of surpluses can provide direct benefits to producers, especially women farmers, and can also benefit consumers by increasing the quantity and diversity of food supplies in local markets. In communities where specific nutritional deficiencies persist or where there appear to be unexploited possibilities for income generation, households can with some support from government services or NGOs improve the diversity and productivity of their traditional gardens. Home gardening can also be a potentially important element in urban food security strategies.

For home garden projects to be successful and sustainable, a number of important elements need to be considered. Since home gardening is a complex and varied production system forming part of a wider household economy, garden interventions to improve nutrition require a good understanding of local conditions so that project goals can be adapted locally. Thus it is necessary to work closely with local farmers, especially with women farmers, to identify resource and other constraints and locally appropriate ways to promote home gardens that are sustainable. To ensure that availability of garden foods translates into nutritional benefits for the whole family, nutrition education and information about nutritional value and utilization of fruits and vegetables in the diet are essential. Promotion of crop diversification requires flexibility regarding choice of species and cropping patterns, encouragement of diversity and cultivation of locally adapted varieties to enhance nutritional value, and attention to soil fertility, pest management, income-earning potential and genetic conservation. Involving women in all aspects of garden management and nutrition training is crucial, as women do most of the work and are responsible for family nutrition. Regular monitoring of garden progress, although costly, could help to resolve problems and to provide information quantifying gardening output and consumption increases it could thus contribute towards inducing policy-makers and planners to direct more investment to the improvement of the home-gardening sector's output. Community organizing for gardening, preferably building on local farmers' and women's organizations, is also a clear prerequisite for sustainability of gardens in the long term.

Urban agriculture

In urban areas the households most at risk of food insecurity and chronic malnutrition belong to the lowest-income groups which cannot afford to purchase adequate food. Many of these households comprise families of recent migrants who have failed to find regular employment. Their income levels are often so low that they can afford to purchase only the cheapest and most basic foods, and since they cannot afford to rent housing they are forced to camp in makeshift shanty towns on the periphery of cities. Such families often cultivate tiny plots of land within their household area and keep small livestock as a basic survival strategy. However, many of the better-established urban residents have also developed their own subsidiary food supply systems which support food purchase from the urban markets.

Urban agriculture, like the street food trade, often tends to be discounted and frowned upon in official circles as a limited, transitory phenomenon practiced only by recent migrants, living in squatter areas, who have not yet adapted to a market economy. In contradiction to this view, a survey covering cities in a number of countries including Ethiopia, Kenya, Senegal, the United Republic of Tanzania and Uganda (IDRC, 1993) showed that urban agriculture makes a significant contribution to the food supplies of many major cities. A Zambian survey showed that urban enterprises can improve household food security, the variety of the diet and intakes of essential micronutrients (see Box 19 and Tables 28 and 29).

Peri-urban commercial cultivation of high-value crops, including tomatoes, onions, green vegetables and fruit, is a growing food supply enterprise for a number of African cities. Such production systems can be very profitable, justifying their high costs in terms of inputs such as irrigation, fertilizers and pesticides. The proximity of production to urban markets is essential to ensure the freshness of such perishable commodities and their contribution of vitamins and minerals to urban diets.

By practicing a diversified form of urban agriculture, poor urban workers are able to meet some of their nutritional requirements, especially those for minerals and vitamins, through the consumption of some of their produce. This capability is important, as marketed vegetables and fruits often tend to be too expensive for low-income urban dwellers. To encourage urban food gardening as a viable food security strategy, assistance is needed in many instances to provide better access to land, water, seeds, community-based extension services, nutrition education and markets.

Box 19 - Survey of urban agriculture in Lusaka, Zambia

Surveys were carried out in low-income areas of Lusaka, which are made up of five types of settlement: two types of squatter areas (A and B), one of which (A) lacks even basic services two types of serviced plots (C and D), one provided by the local authorities (C), and the other provided under a World Bank housing plan (D) and an area of official low-cost public housing (E).

The questionnaire was designed to provide information about the following types of urban cultivation:

· irrigated plot gardens in the back andlor front yard which are cultivated all the year round

· rainy-season gardens, which are usually located on the periphery of the city, i.e. a type of urban allotment, dependent entirely on rain-fed production.

Analysis showed that nearly 60 percent of the low-income households cultivated one or both types of garden (Table 28). The variety of produce from both types of garden is shown in Table 29.

Source: Adapted from Sanyal, 1985.

Table 28 - Extent of urban agriculture in Lusaka, Zambia (percentage of households engaged)


Chapter 5 - Promotion of food and dietary diversification strategies to enhance and sustain household food security

Many people lack adequate amounts of foods that are rich in the nutrients needed for health and a productive life. Chronic undernutrition affects some 215 million people in sub-Saharan Africa, or 43 percent of the population (FAO, 1996b). Deficiencies of iron, vitamin A and iodine are also widespread about 300 million people are affected every year, and a much greater number are at risk of these deficiencies. Malnutrition increases people's vulnerability to infections, causing numerous deaths (see also Chapter 8). In the face of this bleak situation, major efforts are required by national governments and the international community to bring about reductions in malnutrition and micronutrient deficiencies.

Food diversification for stable access and a sustainable food supply

Increased food production and access are crucial to achieving major nutritional improvement. More foods should be produced that are rich in all the essential micronutrients, available in sufficient quantities and accessible to people all year round. This requires the collaboration of people working in agriculture, fishery, forestry, small animal husbandry, industry, marketing, communications, women's participation, home economics and nutrition. The wide application of proven technologies and approaches in these fields, as well as the development of new concepts, will contribute towards solving nutritional problems. The results of research must be transmitted to farmers, and efforts must be made to build on farmers' indigenous knowledge. Consumers, too, need to be involved and educated on how to prevent nutritional deficiencies.

Access to stable and sustainable food supplies is a precondition for the establishment of food security at the household level. Greater and more sustained yields from the farming system will increase the potential access of the household to an adequate diet. Similarly, farming practices that improve the regular flow of a variety of different foods into the household throughout the seasons enhance food security for its members. Promoting appropriate and improved technologies for home preservation and drying of vegetables and fruits at home will reduce wastage and ensure better utilization of fresh produce (e.g. mangoes) available in abundance during the harvest season. Increased food processing through the establishment and strengthening of small-scale agro-industries can contribute to the year-round availability and variety of micronutrient-rich foods in rural and urban markets. Agro-processing industries will not only even out seasonal price fluctuations, but will also create jobs and incomes from such activities as processing, storage, distribution and marketing. Agro-processing will also stimulate demand for farmers' crops and products and give consumers additional choice.

Strategies for food and dietary diversification at the community and household levels include a range of food-based activities that can maximize the availability of adequate amounts and greater variety of nutritious foods. These activities include:

· promotion of mixed cropping and integrated farming systems

· introduction of new crops (such as soybean)

· promotion of underexploited traditional foods and home gardens

· promotion of fishery and forestry products for household consumption

· promotion of improved preservation and storage of fruits and vegetables to reduce waste, post-harvest losses and effects of seasonality

· strengthening of small-scale agro-processing and food industries

· nutrition education to encourage the consumption of a healthy and nutritious diet year round.

Some of these strategies are discussed in this chapter. Diversification must entail management and generation of resources in such a way that all the various measures undertaken collectively work to improve the livelihood of the rural poor.

Mixed cropping

Traditional farming systems already use a diversity of crops in both mixed and relay intercropping as well as integration of crops with livestock and/or aquaculture. Research on cropping patterns and rotations is generating improved methods to ensure greater and more sustained yields. A holistic approach to research on farming systems, combining knowledge of socio-economic constraints and a better understanding of small farmers' conditions, should help in finding solutions.

For small-scale producers, mixed cropping can be associated with potential yield improvements and monetary advantages as well as positive implications for food security, dietary balance and nutrition. Mixed cropping reduces the risk of crop failure. It can also reduce the need for expensive inputs if crop residues from leguminous intercrops, supplemented where appropriate with rock phosphate, are returned to the soil. Mixed and/or rotational cropping offers increased protection from disease and pest damage, thus potentially increasing profitability and income. All of these attributes reduce risk in the food supply system and thus favourably influence food security.

Farming systems based on mixed cropping can extend the harvesting period and help to alleviate seasonal food shortages, thus enhancing the stability of household food access. They can also reduce erosion risks by providing increased soil cover and additional crop residues for use as green manure and mulch. Such characteristics offer gains in sustainability and in stability for the food supply system.

The choice of intercrops usually includes legumes and/or oilseeds such as melon seed, groundnut, soybean or sunflower, together with cereals as the dominant crop. In terms of dietary balance, grain legumes, or pulses, contain more protein than cereals and about ten times as much protein as most roots and tubers (Table 22). More significantly, in composition the proteins in cereals and legumes are complementary to each other.

Proteins are not all equally effective in promoting growth. The quality of a protein is determined by the kind of amino acids it contains and the proportion in which they are present. Good-quality proteins contain all the essential amino acids in proportions capable of promoting growth when they are the only proteins in the diet. Such proteins are known as complete proteins or proteins of high biological value. All animal proteins are complete proteins, and if eaten in adequate amounts they meet all a person's protein needs. Proteins from vegetable sources, such as beans, contain all the essential amino acids, but contain one or more of them in insufficient quantity to meet the needs for growth. Bean proteins are generally rich in lysine, an amino acid often deficient in cereal proteins, and legume proteins are therefore valuable supplements to cereal-based diets. Table 23 shows the amino acid composition and amino acid score of wheat and chickpea (Cicer arietinum), separately and in combination. An optimal protein quality can be obtained by combining wheat and chickpea at a ratio of approximately 2:1.

Table 22 - Comparative energy and protein content of some cereals, tubers, legumes and oilseeds (per 100 g)

Source: FAO/United States Department of Health. Education and Welfare, 1968.

The total protein content of different legumes varies widely, from around 12 percent for some varieties of chickpea to over 35 percent for high-protein cultivars of winged bean (Psophocarpus tetragonolobus) and soybean (Glycine max) (Table 24). Protein content also varies widely among different varieties of the same species. For example, the protein content of pigeon pea (Cajanus cajan) can vary from 13 to 20 percent, depending on the cultivar and the conditions of cultivation.

Table 23 - Essential amino acid content of wheat and chickpea (Cicer arietinum) (mg per g nitrogen in the food)

Source: Siegel and Fawcett, 1976 (quoted in FAO, 1989f).

a Amino acid score = amino acid content in wheat/chickpea mixture - amino acid content in ideal protein (egg) x 100.

Table 24 - Proximate composition of mature, dry winged bean seeds, compared with some commercial dry legume seeds (%)

Source: Vietmeyer, 1975 (quoted in FAO, 1989f).

The diversity of food supplies offered by mixed cropping systems accords well with nutritional security, especially since the young leaves of many grain legumes, such as cowpea, are also utilized as a green vegetable, providing essential minerals such as calcium and iron together with useful amounts of vitamins A and C. Table 25 lists some specific nutrients found in the major plant groups.

Improving mixed cropping technologies through farming systems studies and adaptive research

Farming systems research can contribute to the nutritional wellbeing and food security of households in a number of ways. With its comprehensive, interdisciplinary nature and its aim to improve the viability of small farms, such research is geared towards promoting sustainable livelihoods. It also includes a priority focus on increasing household food production and improving the assets of the farm household.

Farming systems research is directed towards improving the access of farm households to food and income through interventions related to choice of crops and cropping practices, increased use of small livestock, development of labour-saving technologies and improved storage and processing techniques. Thus strategies to encourage food diversification, such as promotion of mixed cropping technologies (including systems integrating crops with livestock and/or aquaculture), should include support for farming systems research and for the efforts of adaptive research planning teams which work directly with farmers in developing locally appropriate systems of integrated farming. Specific emphasis should be given in farming systems research to increasing the micronutrient output of agricultural systems and developing effective storage and preservation techniques for fruits and vegetables that can be employed at the household and community levels.

Table 25 - Specific nutrients found in the major plant groups

Carbohydrates, protein, dietary fibre, a vitamin B complex, a iron, a calcium a

Carbohydrates, protein, some vitamin C

Carbohydrates, protein, dietary fibre, a iron, a calcium, a vitamin B complex a

Vitamin C, vitamin A, iron, calcium, vitamin B complex, dietary fibre

Note: The diets of vulnerable groups may be low in ail these nutrients.

a Particularly high nutrient values are found in the hull.

Support services and advocacy for mixed cropping

Improved agricultural practices for a wider variety of food crops, once disseminated and accepted by the producers, often need support if they are to be widely adopted. For the integration of nutrition objectives into farming systems research, such support may be needed at the policy level. Actors involved in providing support may include government agencies through extension services, together with financial institutions, agricultural banks, farmer groups, fertilizer and seed companies, food industries and other private-sector agencies who may wish to profit from policies for food diversification.

The aim must be to provide timely and appropriate inputs, advice and assistance to farmers and producers to maximize the returns and minimize the risks arising from adoption of new strategies. Development of improved seed, together with advice on cultural practices and required inputs, must generally be accompanied by increased access to low-interest credit and greater security of land tenure to reduce risks in marginal areas. Action will also be required to ensure effective demand and marketing.

Smallholder farmers are profit maximizers and will adopt improved technologies if they are not too risky and are profitable at an early stage in the adoption process. Risk is perceived not only in terms of monetary returns, but also in terms of the stability and sustainability of the household's livelihood, including access to food.

The adoption of strategies to improve the productivity of mixed farming systems, if successful, will create an increased supply of a variety of foods in excess of the immediate demand for food within the producer communities. Therefore, before a food diversification strategy is undertaken, it will be necessary to assess and ensure marketability of excess products. Consumer surveys regarding the promoted crops will be required, together with advocacy and nutrition education to stimulate demand among urban groups, who may have become unfamiliar with some traditional foodstuffs.

The United Nations University Institute for Natural Resources in Africa (UNU/INRA) has commissioned a series of studies in 14 African countries on indigenous food crops and other useful plants, to determine people's knowledge of indigenous crops, the use they make of them and the preparations that are made from them. The aim of the surveys is to provide data for determining the status of, and priorities and strategies for, research and training related to indigenous food crops. Such information would be useful in improving cropping systems utilizing indigenous food crops in planning to enhance sustainability, to reduce risks of crop failure, to diversify production to meet farmers' food needs and to ensure genetic conservation of indigenous African food crops and in promoting improved methods of cultivation, processing and preparation.

In the case of small-grained cereals such as millets and sorghum, improved processing techniques may be necessary to provide products for urban housewives, who have become used to the convenience of rice and of wheat-based baked products such as breads and biscuits. Development of appropriate snack foods based on a wide variety of crops will help provide a market to absorb anticipated surpluses. In addition, widespread dissemination of nutritional information about these products should accompany their marketing.

Many of the foodstuffs produced in diversified farming systems, such as roots and tubers, plantains and bananas, and fruits and leafy vegetables, are highly perishable. As their production is promoted, therefore, transport and marketing facilities need to be enhanced to avoid post-harvest losses, whose high cost is inevitably passed on to the consumer. Agricultural policies favouring diversification should ideally entail a review of all sectors of the food chain from production to consumption, as well as mobilization of support at the national, district and community levels through producer and consumer interest groups.

Gardening for food

In many agricultural communities, people rely on one main staple crop whose seasonality implies a period of food shortage, usually referred to as the lean or the hungry season. Home gardening can often supplement family food supplies during lean periods and can generate added income when other sources of employment and income may be limited, provided enough water is available. Home gardens have mostly been maintained by women, who often water and manure them from domestic wastes and use them to produce early crops such as green maize and the fruits, spices and vegetables needed to prepare relishes.

Home gardens are labour intensive, but as they are usually close to the house, the labour required can be combined with home and child care responsibilities. Children are often responsible for carrying water and for simple maintenance work, and they may also be given a few plants or a small area to tend. Support of home gardening through horticultural training and nutrition education at school, including the establishment and maintenance of a school food production garden, will provide useful training in intensive land management for the next generation.

Home gardening is quickly taking different forms to suit individual lifestyles and work patterns. For example, urban dwellers grow maize in the backyard and quite often in the front garden as well busy traders plant bananas behind their roadside stalls and scatter tomato seeds in damp areas around their compound living area and children bury mango seeds in rubbish heaps and in drains at the side of their houses. Gardening is often rather haphazard and disorganized at this level, with chickens and goats competing for the harvest, but the intention and interest in home gardening are there, waiting to be harnessed.

Unfortunately, home gardens have rarely received official recognition, and families often lack the necessary resources, knowledge and inputs to produce crops as effectively as possible. A survey in Ghana indicated that traditional home garden farming systems have a number of major constraints which need to be removed if the systems are to be successfully promoted (Asare, Oppong and Twum-Ampofo, 1985). Important factors to consider in encouraging the expansion of home gardens include security of land tenure to facilitate long-term investment in home gardens and better extension services, including credit, to promote the wider establishment of home gardens and improve their management.

Home gardens and nutrition

Traditional home gardens continue to be important sources of micronutrients for rural communities. Poor people obtain most of their nutrients from food plants, which are cheaper and more accessible than animal foods. In humid tropical countries, green leafy plants such as Amaranthus s pp., Corchorus spp., Bidens pilosa, Gynandropsis spp., Celosia spp., Basella spp., Solanum scabrum, Solanum americanum, Hibiscus sabdariffa and Vigna unguiculata often grow wild and spontaneously. Traditionally, they have been consumed as leafy vegetables when climatic conditions have made the cultivation of exotic vegetables more difficult. The leaves of these plants tend to be good sources of protein, phosphorus and iron as well as vitamins A and C and in some cases B-group vitamins. In many cases they are of higher overall food value than introduced vegetable species, for example cabbage or tomatoes. Table 26 shows the nutritional content of some green leafy vegetables widely used in Africa.

Through careful selection, a range of fruit and vegetable crops can be cultivated throughout the year to provide a constant supply of micronutrients (see Figure 19). For example, yellow and orange perennial fruits (e.g. mango, papaya, cape gooseberry and guava), fruit vegetables (e.g. tomato, pumpkin, squash, gourd and eggplant), some root vegetables (e.g. carrot and yellow-fleshed sweet potato) and most dark-green leafy vegetables are generally moderate to good sources of vitamins A and C. Also, some leaves and fruits produced by local indigenous trees are consumed in rural areas and are rich in micronutrients, e.g. guavas and loquats. Some sources of nutrition from the home garden are given in Table 27.

Some staple foods also have a role as sources of micronutrients. For instance, leaves of roots and tubers are valuable sources. In many countries of the African humid tropics, leaves of cassava (Manihot esculenta) are also consumed. Millets are rich sources of iron in comparison with other cereals such as wheat or maize.

Fruit and vegetable cultivation presents rather different challenges under low-temperature conditions such as those found in the remote highlands of Ethiopia or Lesotho. In such areas, efforts to extend the production of leafy vegetables into the winter season, for example, need to be based on the selection of cold-tolerant cultivars of Brassica crops such as kale and mustard. Alternatively, it might be advisable to adopt locally appropriate protected cultivation practices, such as the use of simple low plastic tunnels or hotbeds which accumulate solar heat and shield crop plants from exposure to extremely low temperature and wind.

Table 26 - Nutritional content of some green leafy vegetables (per 100 g edible portion)

Baobab leaves (Adansonia digitata)

Bitter feat (Vernonia amygdalina)

Cassava leaf (Manihot esculenta)

Cat's whiskers (Cleome gynandra)

Sweet potato (Ipomoea batatas)

Leaves, cooked, plus groundnuts

FIGURE 19 - Food availability from home food production and supply systems, Nchelenge, Zambia

Source: Adapted from Thuvesson, 1988.

Table 27 - Some sources of nutrition from the home garden

Source: Adapted from WHO/UNICEF, 1985.

For fruit and vegetable crops, staggering planting dates in the case of short-cycle crops and choosing a mixture of early maturing, average and late-maturing varieties for both annual and perennial crops can extend the harvest period. For instance, some varieties of mango tree can be harvested three times a year, with flowering, first budding, ripening and harvesting stages occurring simultaneously on different parts of the same tree. Thus the problem of seasonality of available nutrients, in this case primarily beta-carotene, can be overcome.

Role of women in home gardening

The role of women in home and community gardens is of special importance. In addition to being responsible for producing crops on small plots of land, women, especially those who are elderly, often have good knowledge of indigenous species of green leafy vegetables they know how to prepare them and how to preserve both seeds and produce. In local markets, the main vendors of these crops (fresh or dried) are often women.

Extension services unfortunately tend to focus on the major field crops. Improved planting materials, better cultivars and advice on cultural practices are rarely offered to cultivators of home gardens. Since women do the bulk of the work and are more conscious of and concerned with the nutritional needs of the family, extension advice, credit and agricultural inputs should be provided to them for maximum benefits. The organization of women's groups should be promoted to facilitate their access to inputs, to improve the efficiency of their work and thus to improve the diversity and productivity of gardens.

Home gardening as a development strategy

It is important to distinguish between traditional gardens, which are cultivated independently of any intervention, and promoted gardens, which receive external assistance. Many gardening projects, especially those that promote home gardening for nutritional and income-generating benefits, are supported by external donors and non-governmental organizations (NGOs). The involvement of ministries of agriculture has generally been limited, as horticulture is still given a low priority in overall agricultural development programmes, and home gardening, in spite of its potential output, receives even less attention. Consequently, few agricultural extensionists have been trained in gardening techniques, and even fewer in mixed tropical gardening. Still fewer have the knowledge to promote better diets and nutritional practices.

The neglect of gardening in development strategies is partly explained by the paucity of data on the output of traditional home gardening systems expressed in quantitative and monetary-equivalent terms which could demonstrate a significant contribution to economic output and national development. As a result, most agricultural and research programmes tend to underestimate or discount the actual or potential importance of home gardening as a food security strategy, and in particular as a strategy for meeting micronutrient needs.

However, as more evidence showing the social, economic and nutritional benefits of home gardening is becoming available, some governments and the private sector are showing renewed interest in gardening activities. Case-studies from Bangladesh and Central America that examined the socio-economic aspects of home gardening and its contribution to family consumption and income provide strong evidence that home gardening has significant economic benefits and that it can be a viable strategy for increasing food supplies for family consumption (Marsh, 1994).

In an integrated nutrition/home gardening programme supported by Helen Keller International in Bangladesh, overall vegetable consumption increased by 30 percent, with home gardens supplying 80 percent of vegetables consumed by the family. As most of the income earned from sale of home garden produce was spent on food, the prevalence of malnutrition among children of participating families was also reduced. In a study in Honduras and Nicaragua, the gardens supplied a significant proportion of fruits and vegetables, legumes, roots and tubers, coffee, tea and medicinal plants for home consumption. The combined benefits of home consumption, income earned from sale of garden produce (25 percent of total average income in Bangladesh, although wide variation was recorded in Honduras and Nicaragua) and savings in expenditure on garden produce were judged to make a significant contribution to the household economy.

Data from an FAO-supported project in the Niger promoting the production and consumption of vitamin A-rich foods among women's groups and their families showed that the proportion of healthy children increased in the project areas, in comparison with the non-project villages (IVACG, 1994). The successful ingredients of this project were: a strong emphasis on nutrition education to promote underutilized indigenous foods such as green leaves the cultivation of traditional wild sources of vitamin A and the use of food preservation and solar drying to address the problem of seasonal shortages.

Available evidence clearly suggests that home gardening can result in tangible benefits for the household, including food on the table, extra income and healthy children. Access to home-grown fruits, vegetables, small animals and/or fish ensures a more balanced diet for rural families with limited purchasing power and increases their self-reliance. The sale of surpluses can provide direct benefits to producers, especially women farmers, and can also benefit consumers by increasing the quantity and diversity of food supplies in local markets. In communities where specific nutritional deficiencies persist or where there appear to be unexploited possibilities for income generation, households can with some support from government services or NGOs improve the diversity and productivity of their traditional gardens. Home gardening can also be a potentially important element in urban food security strategies.

For home garden projects to be successful and sustainable, a number of important elements need to be considered. Since home gardening is a complex and varied production system forming part of a wider household economy, garden interventions to improve nutrition require a good understanding of local conditions so that project goals can be adapted locally. Thus it is necessary to work closely with local farmers, especially with women farmers, to identify resource and other constraints and locally appropriate ways to promote home gardens that are sustainable. To ensure that availability of garden foods translates into nutritional benefits for the whole family, nutrition education and information about nutritional value and utilization of fruits and vegetables in the diet are essential. Promotion of crop diversification requires flexibility regarding choice of species and cropping patterns, encouragement of diversity and cultivation of locally adapted varieties to enhance nutritional value, and attention to soil fertility, pest management, income-earning potential and genetic conservation. Involving women in all aspects of garden management and nutrition training is crucial, as women do most of the work and are responsible for family nutrition. Regular monitoring of garden progress, although costly, could help to resolve problems and to provide information quantifying gardening output and consumption increases it could thus contribute towards inducing policy-makers and planners to direct more investment to the improvement of the home-gardening sector's output. Community organizing for gardening, preferably building on local farmers' and women's organizations, is also a clear prerequisite for sustainability of gardens in the long term.

Urban agriculture

In urban areas the households most at risk of food insecurity and chronic malnutrition belong to the lowest-income groups which cannot afford to purchase adequate food. Many of these households comprise families of recent migrants who have failed to find regular employment. Their income levels are often so low that they can afford to purchase only the cheapest and most basic foods, and since they cannot afford to rent housing they are forced to camp in makeshift shanty towns on the periphery of cities. Such families often cultivate tiny plots of land within their household area and keep small livestock as a basic survival strategy. However, many of the better-established urban residents have also developed their own subsidiary food supply systems which support food purchase from the urban markets.

Urban agriculture, like the street food trade, often tends to be discounted and frowned upon in official circles as a limited, transitory phenomenon practiced only by recent migrants, living in squatter areas, who have not yet adapted to a market economy. In contradiction to this view, a survey covering cities in a number of countries including Ethiopia, Kenya, Senegal, the United Republic of Tanzania and Uganda (IDRC, 1993) showed that urban agriculture makes a significant contribution to the food supplies of many major cities. A Zambian survey showed that urban enterprises can improve household food security, the variety of the diet and intakes of essential micronutrients (see Box 19 and Tables 28 and 29).

Peri-urban commercial cultivation of high-value crops, including tomatoes, onions, green vegetables and fruit, is a growing food supply enterprise for a number of African cities. Such production systems can be very profitable, justifying their high costs in terms of inputs such as irrigation, fertilizers and pesticides. The proximity of production to urban markets is essential to ensure the freshness of such perishable commodities and their contribution of vitamins and minerals to urban diets.

By practicing a diversified form of urban agriculture, poor urban workers are able to meet some of their nutritional requirements, especially those for minerals and vitamins, through the consumption of some of their produce. This capability is important, as marketed vegetables and fruits often tend to be too expensive for low-income urban dwellers. To encourage urban food gardening as a viable food security strategy, assistance is needed in many instances to provide better access to land, water, seeds, community-based extension services, nutrition education and markets.

Box 19 - Survey of urban agriculture in Lusaka, Zambia

Surveys were carried out in low-income areas of Lusaka, which are made up of five types of settlement: two types of squatter areas (A and B), one of which (A) lacks even basic services two types of serviced plots (C and D), one provided by the local authorities (C), and the other provided under a World Bank housing plan (D) and an area of official low-cost public housing (E).

The questionnaire was designed to provide information about the following types of urban cultivation:

· irrigated plot gardens in the back andlor front yard which are cultivated all the year round

· rainy-season gardens, which are usually located on the periphery of the city, i.e. a type of urban allotment, dependent entirely on rain-fed production.

Analysis showed that nearly 60 percent of the low-income households cultivated one or both types of garden (Table 28). The variety of produce from both types of garden is shown in Table 29.

Source: Adapted from Sanyal, 1985.

Table 28 - Extent of urban agriculture in Lusaka, Zambia (percentage of households engaged)


Chapter 5 - Promotion of food and dietary diversification strategies to enhance and sustain household food security

Many people lack adequate amounts of foods that are rich in the nutrients needed for health and a productive life. Chronic undernutrition affects some 215 million people in sub-Saharan Africa, or 43 percent of the population (FAO, 1996b). Deficiencies of iron, vitamin A and iodine are also widespread about 300 million people are affected every year, and a much greater number are at risk of these deficiencies. Malnutrition increases people's vulnerability to infections, causing numerous deaths (see also Chapter 8). In the face of this bleak situation, major efforts are required by national governments and the international community to bring about reductions in malnutrition and micronutrient deficiencies.

Food diversification for stable access and a sustainable food supply

Increased food production and access are crucial to achieving major nutritional improvement. More foods should be produced that are rich in all the essential micronutrients, available in sufficient quantities and accessible to people all year round. This requires the collaboration of people working in agriculture, fishery, forestry, small animal husbandry, industry, marketing, communications, women's participation, home economics and nutrition. The wide application of proven technologies and approaches in these fields, as well as the development of new concepts, will contribute towards solving nutritional problems. The results of research must be transmitted to farmers, and efforts must be made to build on farmers' indigenous knowledge. Consumers, too, need to be involved and educated on how to prevent nutritional deficiencies.

Access to stable and sustainable food supplies is a precondition for the establishment of food security at the household level. Greater and more sustained yields from the farming system will increase the potential access of the household to an adequate diet. Similarly, farming practices that improve the regular flow of a variety of different foods into the household throughout the seasons enhance food security for its members. Promoting appropriate and improved technologies for home preservation and drying of vegetables and fruits at home will reduce wastage and ensure better utilization of fresh produce (e.g. mangoes) available in abundance during the harvest season. Increased food processing through the establishment and strengthening of small-scale agro-industries can contribute to the year-round availability and variety of micronutrient-rich foods in rural and urban markets. Agro-processing industries will not only even out seasonal price fluctuations, but will also create jobs and incomes from such activities as processing, storage, distribution and marketing. Agro-processing will also stimulate demand for farmers' crops and products and give consumers additional choice.

Strategies for food and dietary diversification at the community and household levels include a range of food-based activities that can maximize the availability of adequate amounts and greater variety of nutritious foods. These activities include:

· promotion of mixed cropping and integrated farming systems

· introduction of new crops (such as soybean)

· promotion of underexploited traditional foods and home gardens

· promotion of fishery and forestry products for household consumption

· promotion of improved preservation and storage of fruits and vegetables to reduce waste, post-harvest losses and effects of seasonality

· strengthening of small-scale agro-processing and food industries

· nutrition education to encourage the consumption of a healthy and nutritious diet year round.

Some of these strategies are discussed in this chapter. Diversification must entail management and generation of resources in such a way that all the various measures undertaken collectively work to improve the livelihood of the rural poor.

Mixed cropping

Traditional farming systems already use a diversity of crops in both mixed and relay intercropping as well as integration of crops with livestock and/or aquaculture. Research on cropping patterns and rotations is generating improved methods to ensure greater and more sustained yields. A holistic approach to research on farming systems, combining knowledge of socio-economic constraints and a better understanding of small farmers' conditions, should help in finding solutions.

For small-scale producers, mixed cropping can be associated with potential yield improvements and monetary advantages as well as positive implications for food security, dietary balance and nutrition. Mixed cropping reduces the risk of crop failure. It can also reduce the need for expensive inputs if crop residues from leguminous intercrops, supplemented where appropriate with rock phosphate, are returned to the soil. Mixed and/or rotational cropping offers increased protection from disease and pest damage, thus potentially increasing profitability and income. All of these attributes reduce risk in the food supply system and thus favourably influence food security.

Farming systems based on mixed cropping can extend the harvesting period and help to alleviate seasonal food shortages, thus enhancing the stability of household food access. They can also reduce erosion risks by providing increased soil cover and additional crop residues for use as green manure and mulch. Such characteristics offer gains in sustainability and in stability for the food supply system.

The choice of intercrops usually includes legumes and/or oilseeds such as melon seed, groundnut, soybean or sunflower, together with cereals as the dominant crop. In terms of dietary balance, grain legumes, or pulses, contain more protein than cereals and about ten times as much protein as most roots and tubers (Table 22). More significantly, in composition the proteins in cereals and legumes are complementary to each other.

Proteins are not all equally effective in promoting growth. The quality of a protein is determined by the kind of amino acids it contains and the proportion in which they are present. Good-quality proteins contain all the essential amino acids in proportions capable of promoting growth when they are the only proteins in the diet. Such proteins are known as complete proteins or proteins of high biological value. All animal proteins are complete proteins, and if eaten in adequate amounts they meet all a person's protein needs. Proteins from vegetable sources, such as beans, contain all the essential amino acids, but contain one or more of them in insufficient quantity to meet the needs for growth. Bean proteins are generally rich in lysine, an amino acid often deficient in cereal proteins, and legume proteins are therefore valuable supplements to cereal-based diets. Table 23 shows the amino acid composition and amino acid score of wheat and chickpea (Cicer arietinum), separately and in combination. An optimal protein quality can be obtained by combining wheat and chickpea at a ratio of approximately 2:1.

Table 22 - Comparative energy and protein content of some cereals, tubers, legumes and oilseeds (per 100 g)

Source: FAO/United States Department of Health. Education and Welfare, 1968.

The total protein content of different legumes varies widely, from around 12 percent for some varieties of chickpea to over 35 percent for high-protein cultivars of winged bean (Psophocarpus tetragonolobus) and soybean (Glycine max) (Table 24). Protein content also varies widely among different varieties of the same species. For example, the protein content of pigeon pea (Cajanus cajan) can vary from 13 to 20 percent, depending on the cultivar and the conditions of cultivation.

Table 23 - Essential amino acid content of wheat and chickpea (Cicer arietinum) (mg per g nitrogen in the food)

Source: Siegel and Fawcett, 1976 (quoted in FAO, 1989f).

a Amino acid score = amino acid content in wheat/chickpea mixture - amino acid content in ideal protein (egg) x 100.

Table 24 - Proximate composition of mature, dry winged bean seeds, compared with some commercial dry legume seeds (%)

Source: Vietmeyer, 1975 (quoted in FAO, 1989f).

The diversity of food supplies offered by mixed cropping systems accords well with nutritional security, especially since the young leaves of many grain legumes, such as cowpea, are also utilized as a green vegetable, providing essential minerals such as calcium and iron together with useful amounts of vitamins A and C. Table 25 lists some specific nutrients found in the major plant groups.

Improving mixed cropping technologies through farming systems studies and adaptive research

Farming systems research can contribute to the nutritional wellbeing and food security of households in a number of ways. With its comprehensive, interdisciplinary nature and its aim to improve the viability of small farms, such research is geared towards promoting sustainable livelihoods. It also includes a priority focus on increasing household food production and improving the assets of the farm household.

Farming systems research is directed towards improving the access of farm households to food and income through interventions related to choice of crops and cropping practices, increased use of small livestock, development of labour-saving technologies and improved storage and processing techniques. Thus strategies to encourage food diversification, such as promotion of mixed cropping technologies (including systems integrating crops with livestock and/or aquaculture), should include support for farming systems research and for the efforts of adaptive research planning teams which work directly with farmers in developing locally appropriate systems of integrated farming. Specific emphasis should be given in farming systems research to increasing the micronutrient output of agricultural systems and developing effective storage and preservation techniques for fruits and vegetables that can be employed at the household and community levels.

Table 25 - Specific nutrients found in the major plant groups

Carbohydrates, protein, dietary fibre, a vitamin B complex, a iron, a calcium a

Carbohydrates, protein, some vitamin C

Carbohydrates, protein, dietary fibre, a iron, a calcium, a vitamin B complex a

Vitamin C, vitamin A, iron, calcium, vitamin B complex, dietary fibre

Note: The diets of vulnerable groups may be low in ail these nutrients.

a Particularly high nutrient values are found in the hull.

Support services and advocacy for mixed cropping

Improved agricultural practices for a wider variety of food crops, once disseminated and accepted by the producers, often need support if they are to be widely adopted. For the integration of nutrition objectives into farming systems research, such support may be needed at the policy level. Actors involved in providing support may include government agencies through extension services, together with financial institutions, agricultural banks, farmer groups, fertilizer and seed companies, food industries and other private-sector agencies who may wish to profit from policies for food diversification.

The aim must be to provide timely and appropriate inputs, advice and assistance to farmers and producers to maximize the returns and minimize the risks arising from adoption of new strategies. Development of improved seed, together with advice on cultural practices and required inputs, must generally be accompanied by increased access to low-interest credit and greater security of land tenure to reduce risks in marginal areas. Action will also be required to ensure effective demand and marketing.

Smallholder farmers are profit maximizers and will adopt improved technologies if they are not too risky and are profitable at an early stage in the adoption process. Risk is perceived not only in terms of monetary returns, but also in terms of the stability and sustainability of the household's livelihood, including access to food.

The adoption of strategies to improve the productivity of mixed farming systems, if successful, will create an increased supply of a variety of foods in excess of the immediate demand for food within the producer communities. Therefore, before a food diversification strategy is undertaken, it will be necessary to assess and ensure marketability of excess products. Consumer surveys regarding the promoted crops will be required, together with advocacy and nutrition education to stimulate demand among urban groups, who may have become unfamiliar with some traditional foodstuffs.

The United Nations University Institute for Natural Resources in Africa (UNU/INRA) has commissioned a series of studies in 14 African countries on indigenous food crops and other useful plants, to determine people's knowledge of indigenous crops, the use they make of them and the preparations that are made from them. The aim of the surveys is to provide data for determining the status of, and priorities and strategies for, research and training related to indigenous food crops. Such information would be useful in improving cropping systems utilizing indigenous food crops in planning to enhance sustainability, to reduce risks of crop failure, to diversify production to meet farmers' food needs and to ensure genetic conservation of indigenous African food crops and in promoting improved methods of cultivation, processing and preparation.

In the case of small-grained cereals such as millets and sorghum, improved processing techniques may be necessary to provide products for urban housewives, who have become used to the convenience of rice and of wheat-based baked products such as breads and biscuits. Development of appropriate snack foods based on a wide variety of crops will help provide a market to absorb anticipated surpluses. In addition, widespread dissemination of nutritional information about these products should accompany their marketing.

Many of the foodstuffs produced in diversified farming systems, such as roots and tubers, plantains and bananas, and fruits and leafy vegetables, are highly perishable. As their production is promoted, therefore, transport and marketing facilities need to be enhanced to avoid post-harvest losses, whose high cost is inevitably passed on to the consumer. Agricultural policies favouring diversification should ideally entail a review of all sectors of the food chain from production to consumption, as well as mobilization of support at the national, district and community levels through producer and consumer interest groups.

Gardening for food

In many agricultural communities, people rely on one main staple crop whose seasonality implies a period of food shortage, usually referred to as the lean or the hungry season. Home gardening can often supplement family food supplies during lean periods and can generate added income when other sources of employment and income may be limited, provided enough water is available. Home gardens have mostly been maintained by women, who often water and manure them from domestic wastes and use them to produce early crops such as green maize and the fruits, spices and vegetables needed to prepare relishes.

Home gardens are labour intensive, but as they are usually close to the house, the labour required can be combined with home and child care responsibilities. Children are often responsible for carrying water and for simple maintenance work, and they may also be given a few plants or a small area to tend. Support of home gardening through horticultural training and nutrition education at school, including the establishment and maintenance of a school food production garden, will provide useful training in intensive land management for the next generation.

Home gardening is quickly taking different forms to suit individual lifestyles and work patterns. For example, urban dwellers grow maize in the backyard and quite often in the front garden as well busy traders plant bananas behind their roadside stalls and scatter tomato seeds in damp areas around their compound living area and children bury mango seeds in rubbish heaps and in drains at the side of their houses. Gardening is often rather haphazard and disorganized at this level, with chickens and goats competing for the harvest, but the intention and interest in home gardening are there, waiting to be harnessed.

Unfortunately, home gardens have rarely received official recognition, and families often lack the necessary resources, knowledge and inputs to produce crops as effectively as possible. A survey in Ghana indicated that traditional home garden farming systems have a number of major constraints which need to be removed if the systems are to be successfully promoted (Asare, Oppong and Twum-Ampofo, 1985). Important factors to consider in encouraging the expansion of home gardens include security of land tenure to facilitate long-term investment in home gardens and better extension services, including credit, to promote the wider establishment of home gardens and improve their management.

Home gardens and nutrition

Traditional home gardens continue to be important sources of micronutrients for rural communities. Poor people obtain most of their nutrients from food plants, which are cheaper and more accessible than animal foods. In humid tropical countries, green leafy plants such as Amaranthus s pp., Corchorus spp., Bidens pilosa, Gynandropsis spp., Celosia spp., Basella spp., Solanum scabrum, Solanum americanum, Hibiscus sabdariffa and Vigna unguiculata often grow wild and spontaneously. Traditionally, they have been consumed as leafy vegetables when climatic conditions have made the cultivation of exotic vegetables more difficult. The leaves of these plants tend to be good sources of protein, phosphorus and iron as well as vitamins A and C and in some cases B-group vitamins. In many cases they are of higher overall food value than introduced vegetable species, for example cabbage or tomatoes. Table 26 shows the nutritional content of some green leafy vegetables widely used in Africa.

Through careful selection, a range of fruit and vegetable crops can be cultivated throughout the year to provide a constant supply of micronutrients (see Figure 19). For example, yellow and orange perennial fruits (e.g. mango, papaya, cape gooseberry and guava), fruit vegetables (e.g. tomato, pumpkin, squash, gourd and eggplant), some root vegetables (e.g. carrot and yellow-fleshed sweet potato) and most dark-green leafy vegetables are generally moderate to good sources of vitamins A and C. Also, some leaves and fruits produced by local indigenous trees are consumed in rural areas and are rich in micronutrients, e.g. guavas and loquats. Some sources of nutrition from the home garden are given in Table 27.

Some staple foods also have a role as sources of micronutrients. For instance, leaves of roots and tubers are valuable sources. In many countries of the African humid tropics, leaves of cassava (Manihot esculenta) are also consumed. Millets are rich sources of iron in comparison with other cereals such as wheat or maize.

Fruit and vegetable cultivation presents rather different challenges under low-temperature conditions such as those found in the remote highlands of Ethiopia or Lesotho. In such areas, efforts to extend the production of leafy vegetables into the winter season, for example, need to be based on the selection of cold-tolerant cultivars of Brassica crops such as kale and mustard. Alternatively, it might be advisable to adopt locally appropriate protected cultivation practices, such as the use of simple low plastic tunnels or hotbeds which accumulate solar heat and shield crop plants from exposure to extremely low temperature and wind.

Table 26 - Nutritional content of some green leafy vegetables (per 100 g edible portion)

Baobab leaves (Adansonia digitata)

Bitter feat (Vernonia amygdalina)

Cassava leaf (Manihot esculenta)

Cat's whiskers (Cleome gynandra)

Sweet potato (Ipomoea batatas)

Leaves, cooked, plus groundnuts

FIGURE 19 - Food availability from home food production and supply systems, Nchelenge, Zambia

Source: Adapted from Thuvesson, 1988.

Table 27 - Some sources of nutrition from the home garden

Source: Adapted from WHO/UNICEF, 1985.

For fruit and vegetable crops, staggering planting dates in the case of short-cycle crops and choosing a mixture of early maturing, average and late-maturing varieties for both annual and perennial crops can extend the harvest period. For instance, some varieties of mango tree can be harvested three times a year, with flowering, first budding, ripening and harvesting stages occurring simultaneously on different parts of the same tree. Thus the problem of seasonality of available nutrients, in this case primarily beta-carotene, can be overcome.

Role of women in home gardening

The role of women in home and community gardens is of special importance. In addition to being responsible for producing crops on small plots of land, women, especially those who are elderly, often have good knowledge of indigenous species of green leafy vegetables they know how to prepare them and how to preserve both seeds and produce. In local markets, the main vendors of these crops (fresh or dried) are often women.

Extension services unfortunately tend to focus on the major field crops. Improved planting materials, better cultivars and advice on cultural practices are rarely offered to cultivators of home gardens. Since women do the bulk of the work and are more conscious of and concerned with the nutritional needs of the family, extension advice, credit and agricultural inputs should be provided to them for maximum benefits. The organization of women's groups should be promoted to facilitate their access to inputs, to improve the efficiency of their work and thus to improve the diversity and productivity of gardens.

Home gardening as a development strategy

It is important to distinguish between traditional gardens, which are cultivated independently of any intervention, and promoted gardens, which receive external assistance. Many gardening projects, especially those that promote home gardening for nutritional and income-generating benefits, are supported by external donors and non-governmental organizations (NGOs). The involvement of ministries of agriculture has generally been limited, as horticulture is still given a low priority in overall agricultural development programmes, and home gardening, in spite of its potential output, receives even less attention. Consequently, few agricultural extensionists have been trained in gardening techniques, and even fewer in mixed tropical gardening. Still fewer have the knowledge to promote better diets and nutritional practices.

The neglect of gardening in development strategies is partly explained by the paucity of data on the output of traditional home gardening systems expressed in quantitative and monetary-equivalent terms which could demonstrate a significant contribution to economic output and national development. As a result, most agricultural and research programmes tend to underestimate or discount the actual or potential importance of home gardening as a food security strategy, and in particular as a strategy for meeting micronutrient needs.

However, as more evidence showing the social, economic and nutritional benefits of home gardening is becoming available, some governments and the private sector are showing renewed interest in gardening activities. Case-studies from Bangladesh and Central America that examined the socio-economic aspects of home gardening and its contribution to family consumption and income provide strong evidence that home gardening has significant economic benefits and that it can be a viable strategy for increasing food supplies for family consumption (Marsh, 1994).

In an integrated nutrition/home gardening programme supported by Helen Keller International in Bangladesh, overall vegetable consumption increased by 30 percent, with home gardens supplying 80 percent of vegetables consumed by the family. As most of the income earned from sale of home garden produce was spent on food, the prevalence of malnutrition among children of participating families was also reduced. In a study in Honduras and Nicaragua, the gardens supplied a significant proportion of fruits and vegetables, legumes, roots and tubers, coffee, tea and medicinal plants for home consumption. The combined benefits of home consumption, income earned from sale of garden produce (25 percent of total average income in Bangladesh, although wide variation was recorded in Honduras and Nicaragua) and savings in expenditure on garden produce were judged to make a significant contribution to the household economy.

Data from an FAO-supported project in the Niger promoting the production and consumption of vitamin A-rich foods among women's groups and their families showed that the proportion of healthy children increased in the project areas, in comparison with the non-project villages (IVACG, 1994). The successful ingredients of this project were: a strong emphasis on nutrition education to promote underutilized indigenous foods such as green leaves the cultivation of traditional wild sources of vitamin A and the use of food preservation and solar drying to address the problem of seasonal shortages.

Available evidence clearly suggests that home gardening can result in tangible benefits for the household, including food on the table, extra income and healthy children. Access to home-grown fruits, vegetables, small animals and/or fish ensures a more balanced diet for rural families with limited purchasing power and increases their self-reliance. The sale of surpluses can provide direct benefits to producers, especially women farmers, and can also benefit consumers by increasing the quantity and diversity of food supplies in local markets. In communities where specific nutritional deficiencies persist or where there appear to be unexploited possibilities for income generation, households can with some support from government services or NGOs improve the diversity and productivity of their traditional gardens. Home gardening can also be a potentially important element in urban food security strategies.

For home garden projects to be successful and sustainable, a number of important elements need to be considered. Since home gardening is a complex and varied production system forming part of a wider household economy, garden interventions to improve nutrition require a good understanding of local conditions so that project goals can be adapted locally. Thus it is necessary to work closely with local farmers, especially with women farmers, to identify resource and other constraints and locally appropriate ways to promote home gardens that are sustainable. To ensure that availability of garden foods translates into nutritional benefits for the whole family, nutrition education and information about nutritional value and utilization of fruits and vegetables in the diet are essential. Promotion of crop diversification requires flexibility regarding choice of species and cropping patterns, encouragement of diversity and cultivation of locally adapted varieties to enhance nutritional value, and attention to soil fertility, pest management, income-earning potential and genetic conservation. Involving women in all aspects of garden management and nutrition training is crucial, as women do most of the work and are responsible for family nutrition. Regular monitoring of garden progress, although costly, could help to resolve problems and to provide information quantifying gardening output and consumption increases it could thus contribute towards inducing policy-makers and planners to direct more investment to the improvement of the home-gardening sector's output. Community organizing for gardening, preferably building on local farmers' and women's organizations, is also a clear prerequisite for sustainability of gardens in the long term.

Urban agriculture

In urban areas the households most at risk of food insecurity and chronic malnutrition belong to the lowest-income groups which cannot afford to purchase adequate food. Many of these households comprise families of recent migrants who have failed to find regular employment. Their income levels are often so low that they can afford to purchase only the cheapest and most basic foods, and since they cannot afford to rent housing they are forced to camp in makeshift shanty towns on the periphery of cities. Such families often cultivate tiny plots of land within their household area and keep small livestock as a basic survival strategy. However, many of the better-established urban residents have also developed their own subsidiary food supply systems which support food purchase from the urban markets.

Urban agriculture, like the street food trade, often tends to be discounted and frowned upon in official circles as a limited, transitory phenomenon practiced only by recent migrants, living in squatter areas, who have not yet adapted to a market economy. In contradiction to this view, a survey covering cities in a number of countries including Ethiopia, Kenya, Senegal, the United Republic of Tanzania and Uganda (IDRC, 1993) showed that urban agriculture makes a significant contribution to the food supplies of many major cities. A Zambian survey showed that urban enterprises can improve household food security, the variety of the diet and intakes of essential micronutrients (see Box 19 and Tables 28 and 29).

Peri-urban commercial cultivation of high-value crops, including tomatoes, onions, green vegetables and fruit, is a growing food supply enterprise for a number of African cities. Such production systems can be very profitable, justifying their high costs in terms of inputs such as irrigation, fertilizers and pesticides. The proximity of production to urban markets is essential to ensure the freshness of such perishable commodities and their contribution of vitamins and minerals to urban diets.

By practicing a diversified form of urban agriculture, poor urban workers are able to meet some of their nutritional requirements, especially those for minerals and vitamins, through the consumption of some of their produce. This capability is important, as marketed vegetables and fruits often tend to be too expensive for low-income urban dwellers. To encourage urban food gardening as a viable food security strategy, assistance is needed in many instances to provide better access to land, water, seeds, community-based extension services, nutrition education and markets.

Box 19 - Survey of urban agriculture in Lusaka, Zambia

Surveys were carried out in low-income areas of Lusaka, which are made up of five types of settlement: two types of squatter areas (A and B), one of which (A) lacks even basic services two types of serviced plots (C and D), one provided by the local authorities (C), and the other provided under a World Bank housing plan (D) and an area of official low-cost public housing (E).

The questionnaire was designed to provide information about the following types of urban cultivation:

· irrigated plot gardens in the back andlor front yard which are cultivated all the year round

· rainy-season gardens, which are usually located on the periphery of the city, i.e. a type of urban allotment, dependent entirely on rain-fed production.

Analysis showed that nearly 60 percent of the low-income households cultivated one or both types of garden (Table 28). The variety of produce from both types of garden is shown in Table 29.

Source: Adapted from Sanyal, 1985.

Table 28 - Extent of urban agriculture in Lusaka, Zambia (percentage of households engaged)


Chapter 5 - Promotion of food and dietary diversification strategies to enhance and sustain household food security

Many people lack adequate amounts of foods that are rich in the nutrients needed for health and a productive life. Chronic undernutrition affects some 215 million people in sub-Saharan Africa, or 43 percent of the population (FAO, 1996b). Deficiencies of iron, vitamin A and iodine are also widespread about 300 million people are affected every year, and a much greater number are at risk of these deficiencies. Malnutrition increases people's vulnerability to infections, causing numerous deaths (see also Chapter 8). In the face of this bleak situation, major efforts are required by national governments and the international community to bring about reductions in malnutrition and micronutrient deficiencies.

Food diversification for stable access and a sustainable food supply

Increased food production and access are crucial to achieving major nutritional improvement. More foods should be produced that are rich in all the essential micronutrients, available in sufficient quantities and accessible to people all year round. This requires the collaboration of people working in agriculture, fishery, forestry, small animal husbandry, industry, marketing, communications, women's participation, home economics and nutrition. The wide application of proven technologies and approaches in these fields, as well as the development of new concepts, will contribute towards solving nutritional problems. The results of research must be transmitted to farmers, and efforts must be made to build on farmers' indigenous knowledge. Consumers, too, need to be involved and educated on how to prevent nutritional deficiencies.

Access to stable and sustainable food supplies is a precondition for the establishment of food security at the household level. Greater and more sustained yields from the farming system will increase the potential access of the household to an adequate diet. Similarly, farming practices that improve the regular flow of a variety of different foods into the household throughout the seasons enhance food security for its members. Promoting appropriate and improved technologies for home preservation and drying of vegetables and fruits at home will reduce wastage and ensure better utilization of fresh produce (e.g. mangoes) available in abundance during the harvest season. Increased food processing through the establishment and strengthening of small-scale agro-industries can contribute to the year-round availability and variety of micronutrient-rich foods in rural and urban markets. Agro-processing industries will not only even out seasonal price fluctuations, but will also create jobs and incomes from such activities as processing, storage, distribution and marketing. Agro-processing will also stimulate demand for farmers' crops and products and give consumers additional choice.

Strategies for food and dietary diversification at the community and household levels include a range of food-based activities that can maximize the availability of adequate amounts and greater variety of nutritious foods. These activities include:

· promotion of mixed cropping and integrated farming systems

· introduction of new crops (such as soybean)

· promotion of underexploited traditional foods and home gardens

· promotion of fishery and forestry products for household consumption

· promotion of improved preservation and storage of fruits and vegetables to reduce waste, post-harvest losses and effects of seasonality

· strengthening of small-scale agro-processing and food industries

· nutrition education to encourage the consumption of a healthy and nutritious diet year round.

Some of these strategies are discussed in this chapter. Diversification must entail management and generation of resources in such a way that all the various measures undertaken collectively work to improve the livelihood of the rural poor.

Mixed cropping

Traditional farming systems already use a diversity of crops in both mixed and relay intercropping as well as integration of crops with livestock and/or aquaculture. Research on cropping patterns and rotations is generating improved methods to ensure greater and more sustained yields. A holistic approach to research on farming systems, combining knowledge of socio-economic constraints and a better understanding of small farmers' conditions, should help in finding solutions.

For small-scale producers, mixed cropping can be associated with potential yield improvements and monetary advantages as well as positive implications for food security, dietary balance and nutrition. Mixed cropping reduces the risk of crop failure. It can also reduce the need for expensive inputs if crop residues from leguminous intercrops, supplemented where appropriate with rock phosphate, are returned to the soil. Mixed and/or rotational cropping offers increased protection from disease and pest damage, thus potentially increasing profitability and income. All of these attributes reduce risk in the food supply system and thus favourably influence food security.

Farming systems based on mixed cropping can extend the harvesting period and help to alleviate seasonal food shortages, thus enhancing the stability of household food access. They can also reduce erosion risks by providing increased soil cover and additional crop residues for use as green manure and mulch. Such characteristics offer gains in sustainability and in stability for the food supply system.

The choice of intercrops usually includes legumes and/or oilseeds such as melon seed, groundnut, soybean or sunflower, together with cereals as the dominant crop. In terms of dietary balance, grain legumes, or pulses, contain more protein than cereals and about ten times as much protein as most roots and tubers (Table 22). More significantly, in composition the proteins in cereals and legumes are complementary to each other.

Proteins are not all equally effective in promoting growth. The quality of a protein is determined by the kind of amino acids it contains and the proportion in which they are present. Good-quality proteins contain all the essential amino acids in proportions capable of promoting growth when they are the only proteins in the diet. Such proteins are known as complete proteins or proteins of high biological value. All animal proteins are complete proteins, and if eaten in adequate amounts they meet all a person's protein needs. Proteins from vegetable sources, such as beans, contain all the essential amino acids, but contain one or more of them in insufficient quantity to meet the needs for growth. Bean proteins are generally rich in lysine, an amino acid often deficient in cereal proteins, and legume proteins are therefore valuable supplements to cereal-based diets. Table 23 shows the amino acid composition and amino acid score of wheat and chickpea (Cicer arietinum), separately and in combination. An optimal protein quality can be obtained by combining wheat and chickpea at a ratio of approximately 2:1.

Table 22 - Comparative energy and protein content of some cereals, tubers, legumes and oilseeds (per 100 g)

Source: FAO/United States Department of Health. Education and Welfare, 1968.

The total protein content of different legumes varies widely, from around 12 percent for some varieties of chickpea to over 35 percent for high-protein cultivars of winged bean (Psophocarpus tetragonolobus) and soybean (Glycine max) (Table 24). Protein content also varies widely among different varieties of the same species. For example, the protein content of pigeon pea (Cajanus cajan) can vary from 13 to 20 percent, depending on the cultivar and the conditions of cultivation.

Table 23 - Essential amino acid content of wheat and chickpea (Cicer arietinum) (mg per g nitrogen in the food)

Source: Siegel and Fawcett, 1976 (quoted in FAO, 1989f).

a Amino acid score = amino acid content in wheat/chickpea mixture - amino acid content in ideal protein (egg) x 100.

Table 24 - Proximate composition of mature, dry winged bean seeds, compared with some commercial dry legume seeds (%)

Source: Vietmeyer, 1975 (quoted in FAO, 1989f).

The diversity of food supplies offered by mixed cropping systems accords well with nutritional security, especially since the young leaves of many grain legumes, such as cowpea, are also utilized as a green vegetable, providing essential minerals such as calcium and iron together with useful amounts of vitamins A and C. Table 25 lists some specific nutrients found in the major plant groups.

Improving mixed cropping technologies through farming systems studies and adaptive research

Farming systems research can contribute to the nutritional wellbeing and food security of households in a number of ways. With its comprehensive, interdisciplinary nature and its aim to improve the viability of small farms, such research is geared towards promoting sustainable livelihoods. It also includes a priority focus on increasing household food production and improving the assets of the farm household.

Farming systems research is directed towards improving the access of farm households to food and income through interventions related to choice of crops and cropping practices, increased use of small livestock, development of labour-saving technologies and improved storage and processing techniques. Thus strategies to encourage food diversification, such as promotion of mixed cropping technologies (including systems integrating crops with livestock and/or aquaculture), should include support for farming systems research and for the efforts of adaptive research planning teams which work directly with farmers in developing locally appropriate systems of integrated farming. Specific emphasis should be given in farming systems research to increasing the micronutrient output of agricultural systems and developing effective storage and preservation techniques for fruits and vegetables that can be employed at the household and community levels.

Table 25 - Specific nutrients found in the major plant groups

Carbohydrates, protein, dietary fibre, a vitamin B complex, a iron, a calcium a

Carbohydrates, protein, some vitamin C

Carbohydrates, protein, dietary fibre, a iron, a calcium, a vitamin B complex a

Vitamin C, vitamin A, iron, calcium, vitamin B complex, dietary fibre

Note: The diets of vulnerable groups may be low in ail these nutrients.

a Particularly high nutrient values are found in the hull.

Support services and advocacy for mixed cropping

Improved agricultural practices for a wider variety of food crops, once disseminated and accepted by the producers, often need support if they are to be widely adopted. For the integration of nutrition objectives into farming systems research, such support may be needed at the policy level. Actors involved in providing support may include government agencies through extension services, together with financial institutions, agricultural banks, farmer groups, fertilizer and seed companies, food industries and other private-sector agencies who may wish to profit from policies for food diversification.

The aim must be to provide timely and appropriate inputs, advice and assistance to farmers and producers to maximize the returns and minimize the risks arising from adoption of new strategies. Development of improved seed, together with advice on cultural practices and required inputs, must generally be accompanied by increased access to low-interest credit and greater security of land tenure to reduce risks in marginal areas. Action will also be required to ensure effective demand and marketing.

Smallholder farmers are profit maximizers and will adopt improved technologies if they are not too risky and are profitable at an early stage in the adoption process. Risk is perceived not only in terms of monetary returns, but also in terms of the stability and sustainability of the household's livelihood, including access to food.

The adoption of strategies to improve the productivity of mixed farming systems, if successful, will create an increased supply of a variety of foods in excess of the immediate demand for food within the producer communities. Therefore, before a food diversification strategy is undertaken, it will be necessary to assess and ensure marketability of excess products. Consumer surveys regarding the promoted crops will be required, together with advocacy and nutrition education to stimulate demand among urban groups, who may have become unfamiliar with some traditional foodstuffs.

The United Nations University Institute for Natural Resources in Africa (UNU/INRA) has commissioned a series of studies in 14 African countries on indigenous food crops and other useful plants, to determine people's knowledge of indigenous crops, the use they make of them and the preparations that are made from them. The aim of the surveys is to provide data for determining the status of, and priorities and strategies for, research and training related to indigenous food crops. Such information would be useful in improving cropping systems utilizing indigenous food crops in planning to enhance sustainability, to reduce risks of crop failure, to diversify production to meet farmers' food needs and to ensure genetic conservation of indigenous African food crops and in promoting improved methods of cultivation, processing and preparation.

In the case of small-grained cereals such as millets and sorghum, improved processing techniques may be necessary to provide products for urban housewives, who have become used to the convenience of rice and of wheat-based baked products such as breads and biscuits. Development of appropriate snack foods based on a wide variety of crops will help provide a market to absorb anticipated surpluses. In addition, widespread dissemination of nutritional information about these products should accompany their marketing.

Many of the foodstuffs produced in diversified farming systems, such as roots and tubers, plantains and bananas, and fruits and leafy vegetables, are highly perishable. As their production is promoted, therefore, transport and marketing facilities need to be enhanced to avoid post-harvest losses, whose high cost is inevitably passed on to the consumer. Agricultural policies favouring diversification should ideally entail a review of all sectors of the food chain from production to consumption, as well as mobilization of support at the national, district and community levels through producer and consumer interest groups.

Gardening for food

In many agricultural communities, people rely on one main staple crop whose seasonality implies a period of food shortage, usually referred to as the lean or the hungry season. Home gardening can often supplement family food supplies during lean periods and can generate added income when other sources of employment and income may be limited, provided enough water is available. Home gardens have mostly been maintained by women, who often water and manure them from domestic wastes and use them to produce early crops such as green maize and the fruits, spices and vegetables needed to prepare relishes.

Home gardens are labour intensive, but as they are usually close to the house, the labour required can be combined with home and child care responsibilities. Children are often responsible for carrying water and for simple maintenance work, and they may also be given a few plants or a small area to tend. Support of home gardening through horticultural training and nutrition education at school, including the establishment and maintenance of a school food production garden, will provide useful training in intensive land management for the next generation.

Home gardening is quickly taking different forms to suit individual lifestyles and work patterns. For example, urban dwellers grow maize in the backyard and quite often in the front garden as well busy traders plant bananas behind their roadside stalls and scatter tomato seeds in damp areas around their compound living area and children bury mango seeds in rubbish heaps and in drains at the side of their houses. Gardening is often rather haphazard and disorganized at this level, with chickens and goats competing for the harvest, but the intention and interest in home gardening are there, waiting to be harnessed.

Unfortunately, home gardens have rarely received official recognition, and families often lack the necessary resources, knowledge and inputs to produce crops as effectively as possible. A survey in Ghana indicated that traditional home garden farming systems have a number of major constraints which need to be removed if the systems are to be successfully promoted (Asare, Oppong and Twum-Ampofo, 1985). Important factors to consider in encouraging the expansion of home gardens include security of land tenure to facilitate long-term investment in home gardens and better extension services, including credit, to promote the wider establishment of home gardens and improve their management.

Home gardens and nutrition

Traditional home gardens continue to be important sources of micronutrients for rural communities. Poor people obtain most of their nutrients from food plants, which are cheaper and more accessible than animal foods. In humid tropical countries, green leafy plants such as Amaranthus s pp., Corchorus spp., Bidens pilosa, Gynandropsis spp., Celosia spp., Basella spp., Solanum scabrum, Solanum americanum, Hibiscus sabdariffa and Vigna unguiculata often grow wild and spontaneously. Traditionally, they have been consumed as leafy vegetables when climatic conditions have made the cultivation of exotic vegetables more difficult. The leaves of these plants tend to be good sources of protein, phosphorus and iron as well as vitamins A and C and in some cases B-group vitamins. In many cases they are of higher overall food value than introduced vegetable species, for example cabbage or tomatoes. Table 26 shows the nutritional content of some green leafy vegetables widely used in Africa.

Through careful selection, a range of fruit and vegetable crops can be cultivated throughout the year to provide a constant supply of micronutrients (see Figure 19). For example, yellow and orange perennial fruits (e.g. mango, papaya, cape gooseberry and guava), fruit vegetables (e.g. tomato, pumpkin, squash, gourd and eggplant), some root vegetables (e.g. carrot and yellow-fleshed sweet potato) and most dark-green leafy vegetables are generally moderate to good sources of vitamins A and C. Also, some leaves and fruits produced by local indigenous trees are consumed in rural areas and are rich in micronutrients, e.g. guavas and loquats. Some sources of nutrition from the home garden are given in Table 27.

Some staple foods also have a role as sources of micronutrients. For instance, leaves of roots and tubers are valuable sources. In many countries of the African humid tropics, leaves of cassava (Manihot esculenta) are also consumed. Millets are rich sources of iron in comparison with other cereals such as wheat or maize.

Fruit and vegetable cultivation presents rather different challenges under low-temperature conditions such as those found in the remote highlands of Ethiopia or Lesotho. In such areas, efforts to extend the production of leafy vegetables into the winter season, for example, need to be based on the selection of cold-tolerant cultivars of Brassica crops such as kale and mustard. Alternatively, it might be advisable to adopt locally appropriate protected cultivation practices, such as the use of simple low plastic tunnels or hotbeds which accumulate solar heat and shield crop plants from exposure to extremely low temperature and wind.

Table 26 - Nutritional content of some green leafy vegetables (per 100 g edible portion)

Baobab leaves (Adansonia digitata)

Bitter feat (Vernonia amygdalina)

Cassava leaf (Manihot esculenta)

Cat's whiskers (Cleome gynandra)

Sweet potato (Ipomoea batatas)

Leaves, cooked, plus groundnuts

FIGURE 19 - Food availability from home food production and supply systems, Nchelenge, Zambia

Source: Adapted from Thuvesson, 1988.

Table 27 - Some sources of nutrition from the home garden

Source: Adapted from WHO/UNICEF, 1985.

For fruit and vegetable crops, staggering planting dates in the case of short-cycle crops and choosing a mixture of early maturing, average and late-maturing varieties for both annual and perennial crops can extend the harvest period. For instance, some varieties of mango tree can be harvested three times a year, with flowering, first budding, ripening and harvesting stages occurring simultaneously on different parts of the same tree. Thus the problem of seasonality of available nutrients, in this case primarily beta-carotene, can be overcome.

Role of women in home gardening

The role of women in home and community gardens is of special importance. In addition to being responsible for producing crops on small plots of land, women, especially those who are elderly, often have good knowledge of indigenous species of green leafy vegetables they know how to prepare them and how to preserve both seeds and produce. In local markets, the main vendors of these crops (fresh or dried) are often women.

Extension services unfortunately tend to focus on the major field crops. Improved planting materials, better cultivars and advice on cultural practices are rarely offered to cultivators of home gardens. Since women do the bulk of the work and are more conscious of and concerned with the nutritional needs of the family, extension advice, credit and agricultural inputs should be provided to them for maximum benefits. The organization of women's groups should be promoted to facilitate their access to inputs, to improve the efficiency of their work and thus to improve the diversity and productivity of gardens.

Home gardening as a development strategy

It is important to distinguish between traditional gardens, which are cultivated independently of any intervention, and promoted gardens, which receive external assistance. Many gardening projects, especially those that promote home gardening for nutritional and income-generating benefits, are supported by external donors and non-governmental organizations (NGOs). The involvement of ministries of agriculture has generally been limited, as horticulture is still given a low priority in overall agricultural development programmes, and home gardening, in spite of its potential output, receives even less attention. Consequently, few agricultural extensionists have been trained in gardening techniques, and even fewer in mixed tropical gardening. Still fewer have the knowledge to promote better diets and nutritional practices.

The neglect of gardening in development strategies is partly explained by the paucity of data on the output of traditional home gardening systems expressed in quantitative and monetary-equivalent terms which could demonstrate a significant contribution to economic output and national development. As a result, most agricultural and research programmes tend to underestimate or discount the actual or potential importance of home gardening as a food security strategy, and in particular as a strategy for meeting micronutrient needs.

However, as more evidence showing the social, economic and nutritional benefits of home gardening is becoming available, some governments and the private sector are showing renewed interest in gardening activities. Case-studies from Bangladesh and Central America that examined the socio-economic aspects of home gardening and its contribution to family consumption and income provide strong evidence that home gardening has significant economic benefits and that it can be a viable strategy for increasing food supplies for family consumption (Marsh, 1994).

In an integrated nutrition/home gardening programme supported by Helen Keller International in Bangladesh, overall vegetable consumption increased by 30 percent, with home gardens supplying 80 percent of vegetables consumed by the family. As most of the income earned from sale of home garden produce was spent on food, the prevalence of malnutrition among children of participating families was also reduced. In a study in Honduras and Nicaragua, the gardens supplied a significant proportion of fruits and vegetables, legumes, roots and tubers, coffee, tea and medicinal plants for home consumption. The combined benefits of home consumption, income earned from sale of garden produce (25 percent of total average income in Bangladesh, although wide variation was recorded in Honduras and Nicaragua) and savings in expenditure on garden produce were judged to make a significant contribution to the household economy.

Data from an FAO-supported project in the Niger promoting the production and consumption of vitamin A-rich foods among women's groups and their families showed that the proportion of healthy children increased in the project areas, in comparison with the non-project villages (IVACG, 1994). The successful ingredients of this project were: a strong emphasis on nutrition education to promote underutilized indigenous foods such as green leaves the cultivation of traditional wild sources of vitamin A and the use of food preservation and solar drying to address the problem of seasonal shortages.

Available evidence clearly suggests that home gardening can result in tangible benefits for the household, including food on the table, extra income and healthy children. Access to home-grown fruits, vegetables, small animals and/or fish ensures a more balanced diet for rural families with limited purchasing power and increases their self-reliance. The sale of surpluses can provide direct benefits to producers, especially women farmers, and can also benefit consumers by increasing the quantity and diversity of food supplies in local markets. In communities where specific nutritional deficiencies persist or where there appear to be unexploited possibilities for income generation, households can with some support from government services or NGOs improve the diversity and productivity of their traditional gardens. Home gardening can also be a potentially important element in urban food security strategies.

For home garden projects to be successful and sustainable, a number of important elements need to be considered. Since home gardening is a complex and varied production system forming part of a wider household economy, garden interventions to improve nutrition require a good understanding of local conditions so that project goals can be adapted locally. Thus it is necessary to work closely with local farmers, especially with women farmers, to identify resource and other constraints and locally appropriate ways to promote home gardens that are sustainable. To ensure that availability of garden foods translates into nutritional benefits for the whole family, nutrition education and information about nutritional value and utilization of fruits and vegetables in the diet are essential. Promotion of crop diversification requires flexibility regarding choice of species and cropping patterns, encouragement of diversity and cultivation of locally adapted varieties to enhance nutritional value, and attention to soil fertility, pest management, income-earning potential and genetic conservation. Involving women in all aspects of garden management and nutrition training is crucial, as women do most of the work and are responsible for family nutrition. Regular monitoring of garden progress, although costly, could help to resolve problems and to provide information quantifying gardening output and consumption increases it could thus contribute towards inducing policy-makers and planners to direct more investment to the improvement of the home-gardening sector's output. Community organizing for gardening, preferably building on local farmers' and women's organizations, is also a clear prerequisite for sustainability of gardens in the long term.

Urban agriculture

In urban areas the households most at risk of food insecurity and chronic malnutrition belong to the lowest-income groups which cannot afford to purchase adequate food. Many of these households comprise families of recent migrants who have failed to find regular employment. Their income levels are often so low that they can afford to purchase only the cheapest and most basic foods, and since they cannot afford to rent housing they are forced to camp in makeshift shanty towns on the periphery of cities. Such families often cultivate tiny plots of land within their household area and keep small livestock as a basic survival strategy. However, many of the better-established urban residents have also developed their own subsidiary food supply systems which support food purchase from the urban markets.

Urban agriculture, like the street food trade, often tends to be discounted and frowned upon in official circles as a limited, transitory phenomenon practiced only by recent migrants, living in squatter areas, who have not yet adapted to a market economy. In contradiction to this view, a survey covering cities in a number of countries including Ethiopia, Kenya, Senegal, the United Republic of Tanzania and Uganda (IDRC, 1993) showed that urban agriculture makes a significant contribution to the food supplies of many major cities. A Zambian survey showed that urban enterprises can improve household food security, the variety of the diet and intakes of essential micronutrients (see Box 19 and Tables 28 and 29).

Peri-urban commercial cultivation of high-value crops, including tomatoes, onions, green vegetables and fruit, is a growing food supply enterprise for a number of African cities. Such production systems can be very profitable, justifying their high costs in terms of inputs such as irrigation, fertilizers and pesticides. The proximity of production to urban markets is essential to ensure the freshness of such perishable commodities and their contribution of vitamins and minerals to urban diets.

By practicing a diversified form of urban agriculture, poor urban workers are able to meet some of their nutritional requirements, especially those for minerals and vitamins, through the consumption of some of their produce. This capability is important, as marketed vegetables and fruits often tend to be too expensive for low-income urban dwellers. To encourage urban food gardening as a viable food security strategy, assistance is needed in many instances to provide better access to land, water, seeds, community-based extension services, nutrition education and markets.

Box 19 - Survey of urban agriculture in Lusaka, Zambia

Surveys were carried out in low-income areas of Lusaka, which are made up of five types of settlement: two types of squatter areas (A and B), one of which (A) lacks even basic services two types of serviced plots (C and D), one provided by the local authorities (C), and the other provided under a World Bank housing plan (D) and an area of official low-cost public housing (E).

The questionnaire was designed to provide information about the following types of urban cultivation:

· irrigated plot gardens in the back andlor front yard which are cultivated all the year round

· rainy-season gardens, which are usually located on the periphery of the city, i.e. a type of urban allotment, dependent entirely on rain-fed production.

Analysis showed that nearly 60 percent of the low-income households cultivated one or both types of garden (Table 28). The variety of produce from both types of garden is shown in Table 29.

Source: Adapted from Sanyal, 1985.

Table 28 - Extent of urban agriculture in Lusaka, Zambia (percentage of households engaged)


Chapter 5 - Promotion of food and dietary diversification strategies to enhance and sustain household food security

Many people lack adequate amounts of foods that are rich in the nutrients needed for health and a productive life. Chronic undernutrition affects some 215 million people in sub-Saharan Africa, or 43 percent of the population (FAO, 1996b). Deficiencies of iron, vitamin A and iodine are also widespread about 300 million people are affected every year, and a much greater number are at risk of these deficiencies. Malnutrition increases people's vulnerability to infections, causing numerous deaths (see also Chapter 8). In the face of this bleak situation, major efforts are required by national governments and the international community to bring about reductions in malnutrition and micronutrient deficiencies.

Food diversification for stable access and a sustainable food supply

Increased food production and access are crucial to achieving major nutritional improvement. More foods should be produced that are rich in all the essential micronutrients, available in sufficient quantities and accessible to people all year round. This requires the collaboration of people working in agriculture, fishery, forestry, small animal husbandry, industry, marketing, communications, women's participation, home economics and nutrition. The wide application of proven technologies and approaches in these fields, as well as the development of new concepts, will contribute towards solving nutritional problems. The results of research must be transmitted to farmers, and efforts must be made to build on farmers' indigenous knowledge. Consumers, too, need to be involved and educated on how to prevent nutritional deficiencies.

Access to stable and sustainable food supplies is a precondition for the establishment of food security at the household level. Greater and more sustained yields from the farming system will increase the potential access of the household to an adequate diet. Similarly, farming practices that improve the regular flow of a variety of different foods into the household throughout the seasons enhance food security for its members. Promoting appropriate and improved technologies for home preservation and drying of vegetables and fruits at home will reduce wastage and ensure better utilization of fresh produce (e.g. mangoes) available in abundance during the harvest season. Increased food processing through the establishment and strengthening of small-scale agro-industries can contribute to the year-round availability and variety of micronutrient-rich foods in rural and urban markets. Agro-processing industries will not only even out seasonal price fluctuations, but will also create jobs and incomes from such activities as processing, storage, distribution and marketing. Agro-processing will also stimulate demand for farmers' crops and products and give consumers additional choice.

Strategies for food and dietary diversification at the community and household levels include a range of food-based activities that can maximize the availability of adequate amounts and greater variety of nutritious foods. These activities include:

· promotion of mixed cropping and integrated farming systems

· introduction of new crops (such as soybean)

· promotion of underexploited traditional foods and home gardens

· promotion of fishery and forestry products for household consumption

· promotion of improved preservation and storage of fruits and vegetables to reduce waste, post-harvest losses and effects of seasonality

· strengthening of small-scale agro-processing and food industries

· nutrition education to encourage the consumption of a healthy and nutritious diet year round.

Some of these strategies are discussed in this chapter. Diversification must entail management and generation of resources in such a way that all the various measures undertaken collectively work to improve the livelihood of the rural poor.

Mixed cropping

Traditional farming systems already use a diversity of crops in both mixed and relay intercropping as well as integration of crops with livestock and/or aquaculture. Research on cropping patterns and rotations is generating improved methods to ensure greater and more sustained yields. A holistic approach to research on farming systems, combining knowledge of socio-economic constraints and a better understanding of small farmers' conditions, should help in finding solutions.

For small-scale producers, mixed cropping can be associated with potential yield improvements and monetary advantages as well as positive implications for food security, dietary balance and nutrition. Mixed cropping reduces the risk of crop failure. It can also reduce the need for expensive inputs if crop residues from leguminous intercrops, supplemented where appropriate with rock phosphate, are returned to the soil. Mixed and/or rotational cropping offers increased protection from disease and pest damage, thus potentially increasing profitability and income. All of these attributes reduce risk in the food supply system and thus favourably influence food security.

Farming systems based on mixed cropping can extend the harvesting period and help to alleviate seasonal food shortages, thus enhancing the stability of household food access. They can also reduce erosion risks by providing increased soil cover and additional crop residues for use as green manure and mulch. Such characteristics offer gains in sustainability and in stability for the food supply system.

The choice of intercrops usually includes legumes and/or oilseeds such as melon seed, groundnut, soybean or sunflower, together with cereals as the dominant crop. In terms of dietary balance, grain legumes, or pulses, contain more protein than cereals and about ten times as much protein as most roots and tubers (Table 22). More significantly, in composition the proteins in cereals and legumes are complementary to each other.

Proteins are not all equally effective in promoting growth. The quality of a protein is determined by the kind of amino acids it contains and the proportion in which they are present. Good-quality proteins contain all the essential amino acids in proportions capable of promoting growth when they are the only proteins in the diet. Such proteins are known as complete proteins or proteins of high biological value. All animal proteins are complete proteins, and if eaten in adequate amounts they meet all a person's protein needs. Proteins from vegetable sources, such as beans, contain all the essential amino acids, but contain one or more of them in insufficient quantity to meet the needs for growth. Bean proteins are generally rich in lysine, an amino acid often deficient in cereal proteins, and legume proteins are therefore valuable supplements to cereal-based diets. Table 23 shows the amino acid composition and amino acid score of wheat and chickpea (Cicer arietinum), separately and in combination. An optimal protein quality can be obtained by combining wheat and chickpea at a ratio of approximately 2:1.

Table 22 - Comparative energy and protein content of some cereals, tubers, legumes and oilseeds (per 100 g)

Source: FAO/United States Department of Health. Education and Welfare, 1968.

The total protein content of different legumes varies widely, from around 12 percent for some varieties of chickpea to over 35 percent for high-protein cultivars of winged bean (Psophocarpus tetragonolobus) and soybean (Glycine max) (Table 24). Protein content also varies widely among different varieties of the same species. For example, the protein content of pigeon pea (Cajanus cajan) can vary from 13 to 20 percent, depending on the cultivar and the conditions of cultivation.

Table 23 - Essential amino acid content of wheat and chickpea (Cicer arietinum) (mg per g nitrogen in the food)

Source: Siegel and Fawcett, 1976 (quoted in FAO, 1989f).

a Amino acid score = amino acid content in wheat/chickpea mixture - amino acid content in ideal protein (egg) x 100.

Table 24 - Proximate composition of mature, dry winged bean seeds, compared with some commercial dry legume seeds (%)

Source: Vietmeyer, 1975 (quoted in FAO, 1989f).

The diversity of food supplies offered by mixed cropping systems accords well with nutritional security, especially since the young leaves of many grain legumes, such as cowpea, are also utilized as a green vegetable, providing essential minerals such as calcium and iron together with useful amounts of vitamins A and C. Table 25 lists some specific nutrients found in the major plant groups.

Improving mixed cropping technologies through farming systems studies and adaptive research

Farming systems research can contribute to the nutritional wellbeing and food security of households in a number of ways. With its comprehensive, interdisciplinary nature and its aim to improve the viability of small farms, such research is geared towards promoting sustainable livelihoods. It also includes a priority focus on increasing household food production and improving the assets of the farm household.

Farming systems research is directed towards improving the access of farm households to food and income through interventions related to choice of crops and cropping practices, increased use of small livestock, development of labour-saving technologies and improved storage and processing techniques. Thus strategies to encourage food diversification, such as promotion of mixed cropping technologies (including systems integrating crops with livestock and/or aquaculture), should include support for farming systems research and for the efforts of adaptive research planning teams which work directly with farmers in developing locally appropriate systems of integrated farming. Specific emphasis should be given in farming systems research to increasing the micronutrient output of agricultural systems and developing effective storage and preservation techniques for fruits and vegetables that can be employed at the household and community levels.

Table 25 - Specific nutrients found in the major plant groups

Carbohydrates, protein, dietary fibre, a vitamin B complex, a iron, a calcium a

Carbohydrates, protein, some vitamin C

Carbohydrates, protein, dietary fibre, a iron, a calcium, a vitamin B complex a

Vitamin C, vitamin A, iron, calcium, vitamin B complex, dietary fibre

Note: The diets of vulnerable groups may be low in ail these nutrients.

a Particularly high nutrient values are found in the hull.

Support services and advocacy for mixed cropping

Improved agricultural practices for a wider variety of food crops, once disseminated and accepted by the producers, often need support if they are to be widely adopted. For the integration of nutrition objectives into farming systems research, such support may be needed at the policy level. Actors involved in providing support may include government agencies through extension services, together with financial institutions, agricultural banks, farmer groups, fertilizer and seed companies, food industries and other private-sector agencies who may wish to profit from policies for food diversification.

The aim must be to provide timely and appropriate inputs, advice and assistance to farmers and producers to maximize the returns and minimize the risks arising from adoption of new strategies. Development of improved seed, together with advice on cultural practices and required inputs, must generally be accompanied by increased access to low-interest credit and greater security of land tenure to reduce risks in marginal areas. Action will also be required to ensure effective demand and marketing.

Smallholder farmers are profit maximizers and will adopt improved technologies if they are not too risky and are profitable at an early stage in the adoption process. Risk is perceived not only in terms of monetary returns, but also in terms of the stability and sustainability of the household's livelihood, including access to food.

The adoption of strategies to improve the productivity of mixed farming systems, if successful, will create an increased supply of a variety of foods in excess of the immediate demand for food within the producer communities. Therefore, before a food diversification strategy is undertaken, it will be necessary to assess and ensure marketability of excess products. Consumer surveys regarding the promoted crops will be required, together with advocacy and nutrition education to stimulate demand among urban groups, who may have become unfamiliar with some traditional foodstuffs.

The United Nations University Institute for Natural Resources in Africa (UNU/INRA) has commissioned a series of studies in 14 African countries on indigenous food crops and other useful plants, to determine people's knowledge of indigenous crops, the use they make of them and the preparations that are made from them. The aim of the surveys is to provide data for determining the status of, and priorities and strategies for, research and training related to indigenous food crops. Such information would be useful in improving cropping systems utilizing indigenous food crops in planning to enhance sustainability, to reduce risks of crop failure, to diversify production to meet farmers' food needs and to ensure genetic conservation of indigenous African food crops and in promoting improved methods of cultivation, processing and preparation.

In the case of small-grained cereals such as millets and sorghum, improved processing techniques may be necessary to provide products for urban housewives, who have become used to the convenience of rice and of wheat-based baked products such as breads and biscuits. Development of appropriate snack foods based on a wide variety of crops will help provide a market to absorb anticipated surpluses. In addition, widespread dissemination of nutritional information about these products should accompany their marketing.

Many of the foodstuffs produced in diversified farming systems, such as roots and tubers, plantains and bananas, and fruits and leafy vegetables, are highly perishable. As their production is promoted, therefore, transport and marketing facilities need to be enhanced to avoid post-harvest losses, whose high cost is inevitably passed on to the consumer. Agricultural policies favouring diversification should ideally entail a review of all sectors of the food chain from production to consumption, as well as mobilization of support at the national, district and community levels through producer and consumer interest groups.

Gardening for food

In many agricultural communities, people rely on one main staple crop whose seasonality implies a period of food shortage, usually referred to as the lean or the hungry season. Home gardening can often supplement family food supplies during lean periods and can generate added income when other sources of employment and income may be limited, provided enough water is available. Home gardens have mostly been maintained by women, who often water and manure them from domestic wastes and use them to produce early crops such as green maize and the fruits, spices and vegetables needed to prepare relishes.

Home gardens are labour intensive, but as they are usually close to the house, the labour required can be combined with home and child care responsibilities. Children are often responsible for carrying water and for simple maintenance work, and they may also be given a few plants or a small area to tend. Support of home gardening through horticultural training and nutrition education at school, including the establishment and maintenance of a school food production garden, will provide useful training in intensive land management for the next generation.

Home gardening is quickly taking different forms to suit individual lifestyles and work patterns. For example, urban dwellers grow maize in the backyard and quite often in the front garden as well busy traders plant bananas behind their roadside stalls and scatter tomato seeds in damp areas around their compound living area and children bury mango seeds in rubbish heaps and in drains at the side of their houses. Gardening is often rather haphazard and disorganized at this level, with chickens and goats competing for the harvest, but the intention and interest in home gardening are there, waiting to be harnessed.

Unfortunately, home gardens have rarely received official recognition, and families often lack the necessary resources, knowledge and inputs to produce crops as effectively as possible. A survey in Ghana indicated that traditional home garden farming systems have a number of major constraints which need to be removed if the systems are to be successfully promoted (Asare, Oppong and Twum-Ampofo, 1985). Important factors to consider in encouraging the expansion of home gardens include security of land tenure to facilitate long-term investment in home gardens and better extension services, including credit, to promote the wider establishment of home gardens and improve their management.

Home gardens and nutrition

Traditional home gardens continue to be important sources of micronutrients for rural communities. Poor people obtain most of their nutrients from food plants, which are cheaper and more accessible than animal foods. In humid tropical countries, green leafy plants such as Amaranthus s pp., Corchorus spp., Bidens pilosa, Gynandropsis spp., Celosia spp., Basella spp., Solanum scabrum, Solanum americanum, Hibiscus sabdariffa and Vigna unguiculata often grow wild and spontaneously. Traditionally, they have been consumed as leafy vegetables when climatic conditions have made the cultivation of exotic vegetables more difficult. The leaves of these plants tend to be good sources of protein, phosphorus and iron as well as vitamins A and C and in some cases B-group vitamins. In many cases they are of higher overall food value than introduced vegetable species, for example cabbage or tomatoes. Table 26 shows the nutritional content of some green leafy vegetables widely used in Africa.

Through careful selection, a range of fruit and vegetable crops can be cultivated throughout the year to provide a constant supply of micronutrients (see Figure 19). For example, yellow and orange perennial fruits (e.g. mango, papaya, cape gooseberry and guava), fruit vegetables (e.g. tomato, pumpkin, squash, gourd and eggplant), some root vegetables (e.g. carrot and yellow-fleshed sweet potato) and most dark-green leafy vegetables are generally moderate to good sources of vitamins A and C. Also, some leaves and fruits produced by local indigenous trees are consumed in rural areas and are rich in micronutrients, e.g. guavas and loquats. Some sources of nutrition from the home garden are given in Table 27.

Some staple foods also have a role as sources of micronutrients. For instance, leaves of roots and tubers are valuable sources. In many countries of the African humid tropics, leaves of cassava (Manihot esculenta) are also consumed. Millets are rich sources of iron in comparison with other cereals such as wheat or maize.

Fruit and vegetable cultivation presents rather different challenges under low-temperature conditions such as those found in the remote highlands of Ethiopia or Lesotho. In such areas, efforts to extend the production of leafy vegetables into the winter season, for example, need to be based on the selection of cold-tolerant cultivars of Brassica crops such as kale and mustard. Alternatively, it might be advisable to adopt locally appropriate protected cultivation practices, such as the use of simple low plastic tunnels or hotbeds which accumulate solar heat and shield crop plants from exposure to extremely low temperature and wind.

Table 26 - Nutritional content of some green leafy vegetables (per 100 g edible portion)

Baobab leaves (Adansonia digitata)

Bitter feat (Vernonia amygdalina)

Cassava leaf (Manihot esculenta)

Cat's whiskers (Cleome gynandra)

Sweet potato (Ipomoea batatas)

Leaves, cooked, plus groundnuts

FIGURE 19 - Food availability from home food production and supply systems, Nchelenge, Zambia

Source: Adapted from Thuvesson, 1988.

Table 27 - Some sources of nutrition from the home garden

Source: Adapted from WHO/UNICEF, 1985.

For fruit and vegetable crops, staggering planting dates in the case of short-cycle crops and choosing a mixture of early maturing, average and late-maturing varieties for both annual and perennial crops can extend the harvest period. For instance, some varieties of mango tree can be harvested three times a year, with flowering, first budding, ripening and harvesting stages occurring simultaneously on different parts of the same tree. Thus the problem of seasonality of available nutrients, in this case primarily beta-carotene, can be overcome.

Role of women in home gardening

The role of women in home and community gardens is of special importance. In addition to being responsible for producing crops on small plots of land, women, especially those who are elderly, often have good knowledge of indigenous species of green leafy vegetables they know how to prepare them and how to preserve both seeds and produce. In local markets, the main vendors of these crops (fresh or dried) are often women.

Extension services unfortunately tend to focus on the major field crops. Improved planting materials, better cultivars and advice on cultural practices are rarely offered to cultivators of home gardens. Since women do the bulk of the work and are more conscious of and concerned with the nutritional needs of the family, extension advice, credit and agricultural inputs should be provided to them for maximum benefits. The organization of women's groups should be promoted to facilitate their access to inputs, to improve the efficiency of their work and thus to improve the diversity and productivity of gardens.

Home gardening as a development strategy

It is important to distinguish between traditional gardens, which are cultivated independently of any intervention, and promoted gardens, which receive external assistance. Many gardening projects, especially those that promote home gardening for nutritional and income-generating benefits, are supported by external donors and non-governmental organizations (NGOs). The involvement of ministries of agriculture has generally been limited, as horticulture is still given a low priority in overall agricultural development programmes, and home gardening, in spite of its potential output, receives even less attention. Consequently, few agricultural extensionists have been trained in gardening techniques, and even fewer in mixed tropical gardening. Still fewer have the knowledge to promote better diets and nutritional practices.

The neglect of gardening in development strategies is partly explained by the paucity of data on the output of traditional home gardening systems expressed in quantitative and monetary-equivalent terms which could demonstrate a significant contribution to economic output and national development. As a result, most agricultural and research programmes tend to underestimate or discount the actual or potential importance of home gardening as a food security strategy, and in particular as a strategy for meeting micronutrient needs.

However, as more evidence showing the social, economic and nutritional benefits of home gardening is becoming available, some governments and the private sector are showing renewed interest in gardening activities. Case-studies from Bangladesh and Central America that examined the socio-economic aspects of home gardening and its contribution to family consumption and income provide strong evidence that home gardening has significant economic benefits and that it can be a viable strategy for increasing food supplies for family consumption (Marsh, 1994).

In an integrated nutrition/home gardening programme supported by Helen Keller International in Bangladesh, overall vegetable consumption increased by 30 percent, with home gardens supplying 80 percent of vegetables consumed by the family. As most of the income earned from sale of home garden produce was spent on food, the prevalence of malnutrition among children of participating families was also reduced. In a study in Honduras and Nicaragua, the gardens supplied a significant proportion of fruits and vegetables, legumes, roots and tubers, coffee, tea and medicinal plants for home consumption. The combined benefits of home consumption, income earned from sale of garden produce (25 percent of total average income in Bangladesh, although wide variation was recorded in Honduras and Nicaragua) and savings in expenditure on garden produce were judged to make a significant contribution to the household economy.

Data from an FAO-supported project in the Niger promoting the production and consumption of vitamin A-rich foods among women's groups and their families showed that the proportion of healthy children increased in the project areas, in comparison with the non-project villages (IVACG, 1994). The successful ingredients of this project were: a strong emphasis on nutrition education to promote underutilized indigenous foods such as green leaves the cultivation of traditional wild sources of vitamin A and the use of food preservation and solar drying to address the problem of seasonal shortages.

Available evidence clearly suggests that home gardening can result in tangible benefits for the household, including food on the table, extra income and healthy children. Access to home-grown fruits, vegetables, small animals and/or fish ensures a more balanced diet for rural families with limited purchasing power and increases their self-reliance. The sale of surpluses can provide direct benefits to producers, especially women farmers, and can also benefit consumers by increasing the quantity and diversity of food supplies in local markets. In communities where specific nutritional deficiencies persist or where there appear to be unexploited possibilities for income generation, households can with some support from government services or NGOs improve the diversity and productivity of their traditional gardens. Home gardening can also be a potentially important element in urban food security strategies.

For home garden projects to be successful and sustainable, a number of important elements need to be considered. Since home gardening is a complex and varied production system forming part of a wider household economy, garden interventions to improve nutrition require a good understanding of local conditions so that project goals can be adapted locally. Thus it is necessary to work closely with local farmers, especially with women farmers, to identify resource and other constraints and locally appropriate ways to promote home gardens that are sustainable. To ensure that availability of garden foods translates into nutritional benefits for the whole family, nutrition education and information about nutritional value and utilization of fruits and vegetables in the diet are essential. Promotion of crop diversification requires flexibility regarding choice of species and cropping patterns, encouragement of diversity and cultivation of locally adapted varieties to enhance nutritional value, and attention to soil fertility, pest management, income-earning potential and genetic conservation. Involving women in all aspects of garden management and nutrition training is crucial, as women do most of the work and are responsible for family nutrition. Regular monitoring of garden progress, although costly, could help to resolve problems and to provide information quantifying gardening output and consumption increases it could thus contribute towards inducing policy-makers and planners to direct more investment to the improvement of the home-gardening sector's output. Community organizing for gardening, preferably building on local farmers' and women's organizations, is also a clear prerequisite for sustainability of gardens in the long term.

Urban agriculture

In urban areas the households most at risk of food insecurity and chronic malnutrition belong to the lowest-income groups which cannot afford to purchase adequate food. Many of these households comprise families of recent migrants who have failed to find regular employment. Their income levels are often so low that they can afford to purchase only the cheapest and most basic foods, and since they cannot afford to rent housing they are forced to camp in makeshift shanty towns on the periphery of cities. Such families often cultivate tiny plots of land within their household area and keep small livestock as a basic survival strategy. However, many of the better-established urban residents have also developed their own subsidiary food supply systems which support food purchase from the urban markets.

Urban agriculture, like the street food trade, often tends to be discounted and frowned upon in official circles as a limited, transitory phenomenon practiced only by recent migrants, living in squatter areas, who have not yet adapted to a market economy. In contradiction to this view, a survey covering cities in a number of countries including Ethiopia, Kenya, Senegal, the United Republic of Tanzania and Uganda (IDRC, 1993) showed that urban agriculture makes a significant contribution to the food supplies of many major cities. A Zambian survey showed that urban enterprises can improve household food security, the variety of the diet and intakes of essential micronutrients (see Box 19 and Tables 28 and 29).

Peri-urban commercial cultivation of high-value crops, including tomatoes, onions, green vegetables and fruit, is a growing food supply enterprise for a number of African cities. Such production systems can be very profitable, justifying their high costs in terms of inputs such as irrigation, fertilizers and pesticides. The proximity of production to urban markets is essential to ensure the freshness of such perishable commodities and their contribution of vitamins and minerals to urban diets.

By practicing a diversified form of urban agriculture, poor urban workers are able to meet some of their nutritional requirements, especially those for minerals and vitamins, through the consumption of some of their produce. This capability is important, as marketed vegetables and fruits often tend to be too expensive for low-income urban dwellers. To encourage urban food gardening as a viable food security strategy, assistance is needed in many instances to provide better access to land, water, seeds, community-based extension services, nutrition education and markets.

Box 19 - Survey of urban agriculture in Lusaka, Zambia

Surveys were carried out in low-income areas of Lusaka, which are made up of five types of settlement: two types of squatter areas (A and B), one of which (A) lacks even basic services two types of serviced plots (C and D), one provided by the local authorities (C), and the other provided under a World Bank housing plan (D) and an area of official low-cost public housing (E).

The questionnaire was designed to provide information about the following types of urban cultivation:

· irrigated plot gardens in the back andlor front yard which are cultivated all the year round

· rainy-season gardens, which are usually located on the periphery of the city, i.e. a type of urban allotment, dependent entirely on rain-fed production.

Analysis showed that nearly 60 percent of the low-income households cultivated one or both types of garden (Table 28). The variety of produce from both types of garden is shown in Table 29.

Source: Adapted from Sanyal, 1985.

Table 28 - Extent of urban agriculture in Lusaka, Zambia (percentage of households engaged)