Climate change could expand cassava-growing areas across Africa, strengthening the crop’s role in food security, a new study says. However, the research warns that the same conditions may accelerate the spread of a devastating cassava disease.
Researchers say cassava, a key staple for millions of Africans, remains one of the continent’s most climate-resilient crops, with more than half of Africa currently suitable for its production.
Unlike crops such as maize and beans, cassava tolerates heat and drought, making it increasingly important as weather patterns shift.
“Cassava remains one of Africa’s most climate-resilient staple crops, with more than half of the continent currently suitable for its production,” the study found.
Published in the East African Journal of Science, Technology and Innovation, the study used advanced climate and crop modelling to project the distribution of cassava and cassava brown streak disease (CBSD) under mid-century and late-century climate scenarios.
The researchers concluded that cassava-suitable zones are likely to expand significantly by 2050, particularly across sub-Saharan Africa.
“By 2050, climate change could significantly expand cassava-suitable land in Africa, strengthening its role in food security for millions of smallholder farmers,” the study said.
However, the findings raise serious concerns about cassava brown streak disease, one of the most destructive viral diseases affecting the crop. CBSD damages cassava roots, making them inedible and causing severe yield losses.
According to the study, the disease already threatens about one-third of Africa’s land area, with East Africa remaining the hardest-hit region.
“Cassava brown streak disease already threatens about one-third of Africa’s land area and remains one of the most serious risks to cassava production on the continent,” the researchers warned.
Tanzania, Uganda and eastern Democratic Republic of Congo were identified as current hotspots. More worryingly, climate change could enable the disease to spread far beyond its traditional range.
“Climate change is likely to accelerate the spread of cassava brown streak disease, putting more than half of Africa at risk by 2050,” the study found.
West African countries—including Nigeria, Ghana, Ivory Coast and Cameroon—were highlighted as areas of concern, despite having limited historical outbreaks.
“The study warns that West African countries, including Nigeria and Ghana, could become vulnerable to the disease despite limited historical outbreaks,” it said.
The researchers stressed that climate is not the only driver of disease spread. Human activity also plays a major role, particularly the movement of infected planting materials across farms and borders.
“The movement of infected cassava planting materials poses a greater risk for long-distance spread of the disease than climate alone,” the study noted.
Areas with intensive cassava cultivation were also found to face higher disease risk, underscoring the link between farming practices and disease outbreaks.
To protect future food security gains, the researchers urged governments and agricultural agencies to act quickly.
“Expanding cassava production without strong disease control measures could undermine future food security gains,” the study said.
Key recommendations include deploying cassava varieties that are resistant or tolerant to CBSD, strengthening border controls, and ensuring farmers use certified disease-free planting materials.
“Cassava can help Africa adapt to climate change,” the researchers concluded, “but only if the growing threat of cassava brown streak disease is urgently addressed.”
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