Scientists have identified genetic markers of resistance to two deadly viral diseases in cassava varieties of East African origin.
According to the scientists, the cassava varieties — Namikonga and Albert — which are genetically related through a West African cassava variety TME117 are preferred by farmers in Tanzania and have been cultivated in disease hot spots within the country for decades. Cassava brown streak disease (CBSD) and cassava mosaic disease (CMD) devastate cassava production in Africa. Severe CBSD infections may cause yield losses of between 70 and 100 per cent and for CMD, the yield loss could be to 95 per cent, according to the International Institute of Tropical Agriculture (IITA).
CMD is spread throughout Africa, while CBSD previously known to be a low altitude disease confined to the East African coastal lowlands has been reported in some mid to high altitude areas along Lake Victoria and Central African region. Further spread towards West Africa is predicted.