- A 2023 study was awarded the Cozzarelli Award by the Proceedings of the National Academy of Sciences for its work identifying “forgotten” food crops in sub-Saharan Africa that may be more resilient to climate change than the region’s current staples: maize, rice, cassava and potatoes.
- The study found that West Africa and Central Africa will experience the greatest decline in availability of current staple crops by 2070, with maize being the most vulnerable of the staple crops.
- In addition to identifying 52 food products that are likely to be more suitable for the region’s future climate and have more nutritional value than staples, the researchers were also able to introduce some of the overlooked products to local communities.
For many people in Sub-Saharan Africa, Cleome gyandraCommonly known as the spider plant, it is not a food: it is a weed. A tall, leggy plant with almond-shaped star leaves and clusters of white flowers, the spider plant is particularly common in southern and eastern African countries. But until recently, it was something of a ‘forgotten’ crop: sometimes eaten by rural people for sustenance, but mostly neglected in larger food systems. This is despite the fact that its peppery, mustard-flavoured leaves and stems are rich in vitamins, minerals and nutrients – and may be more resilient than other staples in a region rapidly transforming under climate change.
The spider plant is one of 52 crops identified in a 2023 study recently awarded the prestigious Cozzarelli Prize by the Proceedings of the National Academy of Sciences (PNAS). The study examined “forgotten” crops that could help make sub-Saharan food systems more resilient and more nutritious as climate change makes it harder to grow the maize, rice, cassava and potatoes that the region currently relies on.
“The changing environment, along with the need to diversify the food system and eliminate some of the health problems we currently experience, should prompt us to change the way we grow, the way we eat,” says co-author Enoch Achigan-Dako, director of the Laboratory of Genetics, Biotechnology and Seed Sciences at the University of Abomey-Calavi in Benin. “The diversity we need is already there.”
Using climate models projected for the year 2070, the co-authors identified several regions where climate change will likely make it more difficult to grow these staple crops over the next 50 years.
The study found that suitable ranges for these crops are likely to narrow the most in West Africa, falling by 17.7%. The researchers predicted that Central Africa’s staple crops would see their ranges shrink by 14.5%. Of all staple crops, maize is projected to be the most vulnerable to climate change. The study predicted that more than a quarter of current growing locations in West Africa and a third of these locations in Central Africa would experience “new” conditions outside maize’s core bioclimatic niche.
The researchers then compared these future scenarios to the environmental ranges of 138 candidate crops native to Sub-Saharan Africa that were available in gene banks and fields. These were food crops that were “relatively under-researched, under-utilized, or under-promoted in the African context,” but had the nutritional content and growth stability to support healthy diets and local economies in the region, according to the study.
“Often ‘forgotten’ crops have always been in the continent’s food systems,” Achigan-Dako says. “But no one is supporting these crops and no one is producing additional information on the information that farmers are gathering around these resources.”
The researchers found that the current ranges of many of these plants suggested they could thrive in the new, expected climate conditions. From this group, the researchers then narrowed their list to include only plants with high nutrient content.
“If you look at the broader patterns, not just in Africa but globally, there is a kind of trend towards dietary homogenization that is affecting not only our nutrition but also the resilience of food production systems,” says co-author Maarten van Zonneveld, gene bank manager at the World Vegetable Center in Taiwan. “Yet we know there is a nutritional gap all over the world. We want to determine the extent to which we can exploit these [plants] “We want to achieve these double wins, combating climate change and at the same time contributing to ensuring people have access to healthier nutrition.”
For this team, the work isn’t just theoretical. The partnership stems in part from the fact that all of the researchers involved are working on the ground in Africa, with growers and seed banks, to collect and study underutilized plant species and find the best strategies for introducing them to local diets.
They have had some success, including with the spider plant: the ancient weed is now a common sight at farmers markets in Kenya, and Achigan-Dako is working with farmers in Benin to sell directly to consumers. His lab has also had success introducing the mung bean (Vigna radiata) to Benin by sharing seeds with farmers from the World Vegetable Center.
In Eswatini, van Zonneveld and the World Vegetable Center are partnering with schools to introduce hardy, underused vegetables to their gardens, where usually only beans and corn are grown.
“These programs seem like a promising way to engage with young people, provide them with more nutritious meals and also give them exposure to these types of vegetables,” van Zonneveld says. “These will be our future champions and they will take these vegetables with them. This is really part of a long-term solution.”
But the work is not over yet. One problem is that there is still much to learn about local crop diversity; van Zonneveld pointed to a significant knowledge gap, particularly in terms of historical crop records from the Congo Basin.
“This is one of the least researched areas of vegetable diversity on the continent,” he says. Part of the reason for this is that these countries are reliant on imports for their food. In many parts of the region, eating Western-style food is also seen as a sign of wealth, but indigenous peoples and cultures still face discrimination. Additionally, poor infrastructure and ongoing armed conflicts in some countries can make research difficult and expensive.
Moreover, according to Josué Aruna, director of the Congo Basin Conservation Society (CBCS) in the Democratic Republic of Congo, much of the scientific interest in the region has focused on “improved” crops bred for yield and productivity rather than nutrition or hardiness.
“Communities have abandoned their cultural habits in terms of food systems, which has led to less emphasis on them,” says Aruna. “By focusing on food, scientific researchers [improved] “The seeds have put aside the nutritional value, cultural value and economic value of their ancestral seeds.”
But the Congo Basin is not only among the most climate-vulnerable regions, it is also an area of extraordinary biodiversity, with many more “forgotten” crops that could help build resilience.
The shift is starting. The COVID-19 pandemic and supply chain disruptions due to Russia’s war in Ukraine have led many African countries to shift their focus from food security, which centers on access to food, to food sovereignty: “Not just access, but also diversity and choice,” says Famara Diédhiou, a program officer at the Africa Food Sovereignty Alliance (AFSA).
AFSA works with many countries, including those in the Congo Basin, to implement the My Food is African campaign, which promotes local and traditional foods. They also advocate within the African Union for more localized food policies and a greater focus on agroecology.
Achigan-Dako, van Zonneveld, and their colleagues also provide information and seed resources to the U.S. State Department’s Vision for Adapted Crops and Soils (VACS) program, which provides funding to improve the resilience and sustainability of global food systems. In fact, VACS used the crop list from the PNAS study to select its focus crops. The World Vegetable Center is also working on “rescue” missions to study native crops in Benin, Tanzania, Madagascar, and Eswatini, four hotspots of vegetable biodiversity, with the aim of continuing the search for useful plants.
“I think that’s an important message right now, because if you don’t know what you have, you can’t protect it and you can’t use it,” Van Zonneveld says.
The final piece of the puzzle is determining the most effective ways to bring these crops into the mainstream. One aspect of this is working closely with farmers to understand which crops perform well in different areas. The other is making sure newly introduced foods taste good in local cuisines. The World Vegetable Centre is working on this by using mobile kitchens in clinics, shopping centres and supermarkets, testing dishes that include some of the once “forgotten” ingredients, such as black nightshade, leafy amaranth, squash leaves, okra, jute marshmallow and leafy black-eyed peas – all served with, van Zonneveld says, “peanut sauce: very important.”
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Poster Image: WorldVeg and Ministry of Agriculture staff admire the superior variety of okra in Eswatini. Photo courtesy of WorldVeg.
Quotation:
van Zonneveld, M., Kindt, R., McCullin, S., Achigan-Dako, EG, N’Danikou, S., Hsieh, W., … Dawson, I. K. (2023). Forgotten food crops in Sub-Saharan Africa for healthy nutrition in a changing climate. Proceedings of the National Academy of Sciences, 120(14) doi:10.1073/pnas.2205794120
