Cassava can thrive in the most harsh weather conditions, but its production in East Africa now faces a threat from two — cassava mosaic disease and cassava brown streak disease.

According to the Food and Agriculture Organisation, close to $1 billion is lost in Africa to the cassava viruses.

A regional project, Virus Resistant Cassava for Africa (VIRCA) based in Thika in Kenya, is being carried out by the Kenya Agricultural and Livestock Research Organisation (Kalro), the Uganda National Crops Resources Research Institute and the Donald Danforth Plant Science Centre is using genetic modification to improve cassava yields, which have been falling in the recent past.

Farmers are harvesting less than 10 tonnes per hectare compared with Asia and North American where up to 20 tonnes are realised per hectare.

“Close to 100 million people eat cassava in East Africa. We have a problem in Kenya and in other parts of Africa it is even a bigger problem. The problem is not farming practices, but the cassava diseases,” said Simon Gichuki, co-ordinator of the VIRCA project.

Even as the debate surrounding genetic technology continues in the region, Kalro is conducting field tests to identify a cassava variety that can be used to fight viruses.

“Cassava mosaic disease almost wiped out all the cassava in western Kenya in the mid 1990s. Cassava brown streak disease is now common in Coast and Nyanza regions in Kenya. We need to come up with ways of reducing these losses,” Mr Gichuki said.

The eight-month cross-breeding programme being carried out on a one hectare piece of land uses conventional plant breeding in confined field trial experiments to combine genetically transformed brown streak disease-resistant cassava with cassava mosaic disease resistant non-transgenic plants to provide a cassava variety preferred by farmers.