Cassava disease threatens food security

The International Institute of Tropical Agriculture (IITA) has warned that food security in Nigeria is being threatened by the resurgence of a viral disease attacking the staple crop, cassava. The new, more virulent strain of the cassava mosaic disease could wipe out the entire crop in the southern cassava belt in a few years, the institute warned on Monday, after an emergency workshop in the southern city of Port Harcourt. "The destructive cassava mosaic disease, which almost wiped out the cassava plant in Nigeria in the early 1970s, is back in a more devastating form," according to the statement, sent to IRIN on Monday. The new strain of cassava mosaic disease combines features of strains earlier identified in West Africa and East Africa, it added. An official of the research institute, James Agba, said diagnostic surveys conducted in Cameroon, Nigeria, Ghana and Togo had detected the new strain of the disease at work. The IITA had already started work to counter the spread of the disease, he added. The disease presents as tiny, black mosaic dots on the leaves and produces powdery substances on the stems of the cassava plant. It leaves affected plants stunted and depresses their yield by more than 80 percent. The cassava plant, indigenous to South America, was introduced to West Africa during the slave trade in the 18th and 19th centuries. Its short maturity period (six months) and ability to grow in both dry and rainy seasons quickly made it a staple crop. Nigeria is currently a leading world producer of cassava.