Seeds, superfoods and soils for resilience, oh my!

By Emily Alpert

Smallholder farmers in Africa are no strangers to climate change. The first impacts can already be felt. Erratic rainfall, shorter growing seasons and prolonged droughts mean that crops suffer, as do the livelihoods of smallholder farmers. To meet the demands of a growing global and African population, crop productivity will have to be increased. Under climate change conditions, this will have to be achieved with fewer resources and smarter interventions. Seeds, superfoods, and soils all offer some solutions.


Farmer resilience to climate change can be strengthened in many ways: income diversification, secure land rights or better access to insurance policies are all examples. Resilience can also come in the form of a seed.

Drought-tolerant maize varieties hope to do just that. These seeds are bred with the ability to withstand periods of low and erratic rainfall. The public-private partnership Water Efficient Maize for Africa (WEMA), developed under the coordination of the African Agricultural Technology Foundation (AATF), aims to develop drought-tolerant and insect-protected maize using conventional breeding, marker-assisted selection, and biotechnology, with a goal to make these varieties available royalty-free to smallholder farmers in Sub-Saharan Africa through African seed companies. So far, conventional drought-tolerant maize hybrids – varieties developed by crossing two inbred lines – have been released in Kenya and South Africa.


While WEMA offers a technological solution, simply choosing to grow crops that are already inherently suitable to dry climates is another option. Some of these crops, such as the orange-fleshed sweet potato, build resilience from many directions. Orange-fleshed sweet potatoes were bred to be high in beta-carotene that converts to Vitamin A in the body.

Globally two billion people suffer from micro-nutrient deficiencies. Around 127 million preschool children or about one-quarter of all preschool children in high-risk countries are vitamin A deficient. Vitamin A deficiency results in eye damage, blindness and even death.

sweet potatoClearly of tremendous importance in the global effort to reduce undernutrition, we can be thankful that sweet potatoes grow in water stressed and hot climates. In fact, their preferred average temperature is 24 °C (75 °F), abundant sunshine and warm nights. Sweet potatoes also like between 750-1,000 mm (29-39 inches) of rainfall, but can tolerate far less: 500mm (20 inches). While sweet potatoes are sensitive to drought during the initial first two-months of growing, early maturing varieties help to ensure that these roots will survive this sensitive period. To boot, sweet potatoes also have few natural enemies and can even be grown in poor soils with limited fertiliser.

Sweetpotoes, hard as it is to believe, are not perfect, and the vines do suffer in the dry season.  Dr. Maria Andrade – the mother of orange-fleshed sweet potatoes – and her team of researchers at the International Potato Center (CIP) are on the case. They are trialling a method called Sweet potato Storage in Sand (SSS) to assist smallholders in preserving vines during the dry season. SSS allows for sweet potatoes to be stored for up to five months as planting material and then planted in beds six to eight weeks before the rains arrive.  SSS is new to Africa but has proved successful in the USA. CIP are also working to develop varieties that are higher in other essential nutrients – iron, zinc – and enhanced to withstand even greater levels of drought.

Fixing Soil Nutrients  

Poor soils are not ideal – no matter what the crop. Due to a combination of inherent characteristics and poor management practices, much of Africa’s soils are degraded. In fact, 26% are severely degraded. The estimated loss in sub-Saharan Africa alone is $68 billion per year, affecting 180 million people.

While access to fertiliser, and often the right type of fertiliser and nutrients are still hard to come by in most parts of Africa, some plants and trees help to fill the gap. nitrogenMany legumes such as peas, clover, alfalfa and even soya take are known for their ability to take nitrogen from the atmosphere and return it to the soil.  The nitrogen is first used to help the plants grow and when the plant dies, the nitrogen is released into the soil for other plants to use.

The rhizobia – bacteria responsible for fixing nitrogen – look like little nodules on the plant’s root hairs. According to Dr. Bashir Jama, head of the Soil Health Program at the Alliance for a Green Revolution in Africa (AGRA) – the pink nodules are a sign that the plant is effectively fixing nitrogen. As the rhizobia bacteria takes effect, the plant responds by releasing a compound called leghemogbin which is similar to hemoglobin and also red in colour turning the nodules pink.

Beyond demos

Building resilience through improved seeds, plant varieties, storage systems, or nitrogen-fixing bacteria only works if farmers adopt these technologies and practices. Without knowing that a technology will work, the investment – in time, labour or capital – can often be too great.

AGRA’s Beyond Demos programme works with farmers to demonstrate the impacts that can be achieved when using ‘best-bet’ agronomic practices plus the right types and amounts of soil nutrients. In the village of Boavista, about 10km outside of Chimoio in the Manica province of Mozambique, members of the Zano Ramambo farmer’s organization are managing experimental sites consisting of mother and baby trials.

In the mother trial there were six experimental plots with different soil treatments for maize.  As a soil pit demonstrated, the soils in this region are very deep and well structured but extremely deficient in nutrients. Using mulch alone, as was demonstrated on one plot, produced very low yields. The best plot was that with a balanced blend of Nitrogen, Phosphorous, and Potassium (NPK) together with various micronutrients and crucially lime. When used correctly, it promises to yield 4-6 tons per hectare – an achievement on par with European averages.


A visit to AGRA’s Soil Health Program in Chimoio and Maria Andrade’s sweet potato research station near Maputo have a lot of lessons to offer about resilience. Resilience can come from a seed, but it is also the product of continued research and investment in that seed and its wider support network. Just as seeds need to be nurtured, so do soils and the needs of the farmers who plant them.

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