G.W. Otim-Nape, J. Legg, J.M. Thresh and T. Alicai
A severe cassava mosaic disease (CMD) was first reported in November 1988 in Buruli county, Luwero district where it had destroyed over two thousand hectares of cassava. It subsequently spread and covered the rest of the country causing serious devastation. Each year since 1988, the epidemic moved southwards, towards Kampala, at a rate approximately 20-30km per annum. It is concluded that the epidemic originated from more than one place from northern parts of Uganda and spread southwards along a broad from several km wide. The cause of the epidemic has been investigated. Because the C isolates differed consistently, and in a characteristic way, from both EACMV and ACMV, they have been subsequently referred to as the Uganda variant (UgV), which has arisen through recombination between the two similar viruses which have been in East Africa since 1894. The role of the whitely in the epidemic development and sustainability of the epidemic and methods of the epidemic control are discussed.