Cassava is a major source of food in Africa, and it's under increasing threat from two devastating diseases. This week researchers and development organizations meeting in Bellagio, Italy, pledged to step up their efforts to prevent the spread of the diseases and safeguard the crop.
About 300 million people in Africa depend on cassava, a root that is ground into flour, used as starch, biofuel, and for brewed into beer. For a century, production across the continent has been hindered by outbreaks of cassava mosaic disease, which is caused by several viruses. Breeding of new varieties helped get this problem mostly under control, but in the last decade cassava brown streak disease (CBSD) has emerged as an even more serious concern. The virus can wipe out the root crop underground without a farmer noticing until harvest.
CBSD has been afflicting crops in east and central Africa. Now there are worrying signs it is moving west. Whiteflies, which spread the viruses, have been found east of the Congo, the world's third largest source of cassava. If the disease were to reach into Nigeria, Congo, and Ghana, which all grow a lot of cassava, "it would be a human disaster, an economical disaster, and would translate to a lot of instability," says Claude Fauquet of the International Center for Tropical Agriculture in Cali, Colombia.
Fauquet helped organize the meeting, which included representatives from 22 organizations, including the World Bank, U.N. Food and Agriculture Organization, the Gates Foundation, and others. "There is urgency to get organized internationally to better control these diseases," Fauquet says.
Attendees at the meeting committed to developing a surveillance system to prevent outbreaks from blowing up into epidemics. The disease is "relatively easy to eradicate when you have a few [infected] acres," Fauquet says. The surveillance system would first be implemented in Africa and then perhaps expanded to Southeast Asia, which is now also growing cassava. In a second step, the partnership will focus on eradicating the disease where it is already present. The third component is to create a public-private partnership that will provide farmers with high-quality, disease-free seed. They will also begin and coordinate research projects, such as breeding plants that can resist the disease and the white flies.
The groups did not discuss a price tag for these projects, but within 2 months they will publish a road map of actions needed and then work out a budget.