Ogbe F.O, G.I. Atiri, G. Thottappilly, A.G.O. Dixon, H.D. Mignouna and F.M. Quin
A better knowledge on the occurrences of cassava geminiviruses namely Afncan cassava mosaic (ACMV) and East African cassava mosaic (EACMV) begomoviruses would enhance effective control of cassava mosaic disease (CMD) in Africa. A diagnostic survey conducted in Nigeria in 1997 indicated that ACMV and EACMV occurred both in single and double infections. These findings together with recent detection of EACMV in Cameroun, Togo, Guinea, western Kenya, western Tanzania and north-eastern Zambia where only ACMV was known to occur provide evidence for probable random occurrences of both viruses in sub-Saharan Africa. The implications of double infection of the two viruses on the development of new strains/variants that could cause outbreak of severe CMD is noted. The need to continually develop cassava clones with durable host-plant resistance is emphasised.