Harnessing the benefits of African leafy vegetables for smallholder farmers and their households

South Africa is one of the most unequal countries in the world; 55% of the population live in poverty with 25% in extreme poverty. Food shortages and poor nutrition affect many households, with 24% of under-fives stunted. Poor nutrition is not just a lack of macronutrients but of micronutrients, minerals and vitamins which have an impact on health. 17% of children and 19% of pregnant women in South Africa are deficient in vitamin A. The smallholder sector comprises approx. 2 million farms most of which are on land with degraded soil and low rainfall; these areas have the highest prevalence of poverty and food and nutrition problems. Productivity is low. Most areas in South Africa are prone to drought and 8 out of 9 provinces have received progressively less rainfall since 1970. Inadequate rainfall causes reduced yields, especially in the smallholder farming sector where farmers cannot afford irrigation. Hence, there is an urgent need to develop strategies to ensure sufficient nutritional food and a source of income for these farmers and their households in a sustainable manner, i.e. produced in a way that is resilient to environmental fluctuation and does not deplete natural resources.

Although neglected and underutilised, African leafy vegetables (ALVs) offer unique opportunities to diversify farming systems, contribute to climate change adaptation, ensure food security, alleviate poverty, increase income and improve human health (particularly malnutrition and lack of micronutrients). Most communities affected by poverty and undernutrition live in areas rich in biodiversity, including ALVs. A key attribute of ALVs is their high nutritional content with many studies indicating higher levels of vitamins and minerals compared to cultivated vegetables, such as cabbage and spinach. The consumption of ALVs is in decline in many rural communities which has contributed to poor diets and increased incidence of nutritional deficiencies. Currently, ALVs are harvested from the wild rather than cultivated. This is unsustainable and already a decline in the wild population of ALVs has been reported due to over-harvesting and lack of seed production.

ALVs are well-adapted to local growing conditions. ALVs grow on marginal land with little input. They are hardy and able to thrive in both drought and flood times. As a result ALVs are available during harsh environmental conditions when most cultivated crops would have failed, and indeed harvesting and consumption of ALVs from the wild increases in rural regions during times of drought to help meet food shortages. The cultivation of ALVs would play a role in increasing agro-biodiversity which helps suppress pests and disease, as well as protect against the effects of climate variability. ALVs also have the potential to contribute to household income because of their relatively high value. With increased reliability of supply, it would be possible to develop new value chains such as selling through supermarkets.

Thus increased cultivation and utilisation of ALVs would improve nutrition, provide resilience of food supply in the face of climate change, improve the environmental sustainability of smallholder agriculture and diversify income opportunities. However, to help increase cultivation and utilisation of ALVs it is necessary to develop lines which maintain their ability to grow with low inputs and under fluctuating climate, and maintain their nutritional benefits but have increased yield. In this proposal we will develop such varieties for the most common ALV in Southern Africa, Amaranthus, using a combination of molecular analysis, metabolic profiling of nutrient content, genomics, participatory breeding with smallholder farmers, and analysis of susceptibility to pests. We will deliver improved lines which can then be promoted by the Agricultural Research Council in South Africa to improve the nutrition, livelihoods and environmental sustainability of smallholder households.

Food shortages and poor nutrition (lack of micronutrients, minerals and vitamins) affect many households in South Africa with 24% of under-fives stunted and 17% of children and 19% of pregnant women deficient in vitamin A. The highest prevalence of poverty and food and nutrition insecurity occurs in rural regions; the ~2 million smallholder farmers have low productivity and little ability to cope with fluctuating climatic conditions. Although neglected and underutilized, African leafy vegetables, such as Amaranth, offer unique opportunities for sustainable development. Leafy amaranth can provide nutritional, livelihood and environmental benefits for smallholder farmers, resulting from dietary diversification, income from a high value low input crop as well as its water use efficiency from adaptation to growing on marginal land. The overall aim of this proposal is to improve the productivity of Amaranth to facilitate its uptake as a cultivated crop amongst smallholder farmers in Southern Africa to realise these benefits.

In this proposal we will capture the diversity of locally adapted amaranth accessions and use this diversity in participatory plant breeding to enhance yield and performance under smallholder low input agriculture. We will use a combination of genetics, genomics, transcriptomics and metabolite profiling to assess variation in nutritional content and identify regions of the genome, and candidate genes, regulating nutrient accumulation. We will also investigate how nutrient content correlates with resistance to key pests. The data, knowledge and new lines produced during the proposed work will enable improvement of yield whilst ensuring nutritional value and key traits for Amaranth's contribution to diversified, environmentally resilient farming systems are maintained during selection.

The direct beneficiaries of this research will be smallholder farmers in South Africa and sub-Saharan Africa more broadly. In South Africa 56% of the population live in poverty with 25% (13.8 million) in extreme poverty. Food shortages and poor nutrition affect many households, with 24% of under-fives stunted. Poor nutrition is not just a lack of macronutrients but of micronutrients, minerals and vitamins (for example, 17% of children and 19% of pregnant women in South Africa are deficient in vitamin A) with resulting impacts on health. Poverty, food insecurity and malnutrition are highest in the rural areas, where the approx. 2.8 million smallholder farmers and their households live. This land is typically poor quality with degraded soil and low and erratic rainfall. These poor conditions, lack of access to improved crop varieties, and low input agricultural systems, for example, smallholder farmers cannot afford irrigation infrastructure, all contribute to the low productivity of smallholder farmers.

Smallholder farmers will benefit from this project by access to improved lines of the African leafy vegetable, amaranth, for growing on their farms. Growing and consuming these improved lines will increase the nutritional content of smallholder household diets, provide agro-ecological benefits in terms of pest and disease incidence, improve food security by being a climate-tolerant crop, and provide opportunities for income generation through local and potentially national markets.

African leafy vegetables (ALVs) are used to prepare sauces and relish to accompany maize meal across Africa. ALVs are high in nutrients (greater nutrient content than exotic vegetables such as cabbage) and can grow on marginal land with few inputs. They are well-adapted to local conditions and can thrive at times of drought, when staple crops are likely to fail. Hence consumption of ALVs can improve nutrition and help meet food shortages. However, ALVs are currently harvested from the wild and wild populations of some ALVs are already declining due to over-harvesting and subsequent lack of seed production. Harvesting from the wild also means that smallholder households benefitting from ALVs have no control over availability, which is both unpredictable and variable. Consumption is in decline in many rural communities contributing to poor diets and increased incidence of nutritional deficiencies. Cultivation of ALVs would help enhance the environmental sustainability of smallholder farms. Increased crop diversity reduces pest and disease incidence, and the water use efficiency of ALVs provides resilience to climate change impacts and limited water availability. Furthermore, cultivation of ALVs can provide income opportunities for smallholders due to their high value.

A key barrier to cultivation, consumption and enterprise development around ALVs is the availability of lines that combine beneficial nutritional/drought tolerance/hardiness traits, with increased yield. In this project we will generate improved lines of amaranth, as well as the knowledge and tools to drive further amaranth breeding after the end of the project. Leafy amaranth is one of the most common ALVs in sub-Saharan Africa and in South Africa occurs across all geographical regions and is consumed across all ethnic groups. Improving the traits, cultivation and utilisation of amaranth would thus impact a large proportion of the sub-Saharan population. The lines we generate (both immediately and after further breeding) will be used in ongoing programmes to promote the cultivation and utilisation of these vegetables by farmers, especially women and other vulnerable groups, and to build the whole value chain from seed to markets. The knowledge and tools we generate will be shared with African plant breeders outside South Africa, via the African Orphan Crop Consortium, to enhance amaranth breeding (and subsequent increased cultivation and consumption) across sub-Saharan Africa.