As the global climate changes and the going gets tough for other staple crops, tough but neglected cassava may finally get going.

Cassava may be about to experience something of a heyday. With climate change expected to take its toll on staples like rice, wheat and maize, the potential of cassava — famously hardy when the going gets tough — is growing by the day.

Climate change models run by the International Center for Tropical Agriculture (CIAT by its Spanish acronym) show that by 2050 almost one fifth of cassava-growing land is expected to benefit from rising temperatures and changes in rainfall. This is good news for one of the world’s most important sources of carbohydrates, and improving cassava varieties to make them even more resilient could result in an additional 60 million hectares of land becoming suitable for cassava production.

Improving cassava varieties to make them more resilient to climate change could result in an additional 60 million hectares of land becoming suitable for production of this crop. Photo: Neil Palmer, CIAT.

Grown across the tropics for its energy-packed tuberous roots, cassava is of particular value to smallholders because of its remarkable ability to tolerate drought and poor soils. Cassava is predominantly grown as a food crop in Africa and Latin America, while Asia leads in the industrial production of the crop. Processing cassava starch is a major employer.

Improved cassava varieties that capitalize on the crop’s inherent resilience could become the cornerstone of climate change adaptation to protect food supplies and livelihoods. This is particularly true in Latin America — cassava’s center of diversity — which has much to gain from improved varieties. While some parts of the region are likely to see increases in cassava suitability, models show large areas where suitability is expected to fall. It is at these frontiers that improved cassava could have the greatest impact.

According to Andy Jarvis, a climate change expert and the leader of CIAT’s Decision and Policy Analysis Program, it is essential to develop cassava lines with improved tolerance to heat, cold, drought and flooding.

“The message coming out of the modeling is that there is no single trait that provides global gains for cassava,” says Jarvis. “Instead, breeding must tackle multiple constraints.”

If this happens, new technologies could benefit one third of current cassava fields in Latin America by 2050 and nearly triple the area suitable for cassava production. But, Jarvis adds, there is no time to lose.

“The scientific community must make these decisions now,” he says. “It takes a minimum of a decade from beginning work on crop improvement to getting the new variety into farmers’ fields. So we need to look closely at what the models tell us about the future challenges and tailor our research to match. With the right science and the right priorities, cassava could become a super crop, but we have to move now.”

Jarvis stressed the importance of research-and-development networks, such as the Latin American and Caribbean Consortium to Support Cassava Research and Development (CLAYUCA by its Spanish acronym), for ensuring that new technologies reach farmers quickly. The CIAT-coordinated network, which celebrated its 10th anniversary in July, has members from the public and private sectors in 16 countries, all working to improve the generation and exchange of new cassava-related technologies. The initiative has been responsible for the development, adaptation and transfer of several technological platforms for cassava production, processing and utilization that are helping farmers increase yields and incomes and improve livelihoods.

“Collaboration and dissemination are essential for climate change adaptation,” says Jarvis. “Networks like CLAYUCA are vastly improving the impact of cassava research. They enable high-speed links between laboratories and farmers’ fields.”

Uncertainties remain about the impact of climate change on cassava’s susceptibility to pests and diseases and, therefore, the extent to which increases in area planted to the crop will mean higher production. Tropical whitefly — infestations of which have wiped out entire plantations in Asia and Africa — have been reported in southern Brazil, where cassava starch processing is about to boom.

Jarvis recognizes the limitations of climate models but stresses the need for action.

“There’s simply no time to wait and see,” he says. “With the right research combined now with the right partnerships and the right methods for dissemination, cassava can fulfill its potential as a crop capable of thriving in the face of climate change.”