Cassava Genotypes Response to the African Cassava Mosaic Disease in Rainforest Agro ecological Zone

Abstract

Twelve cassava genotypes were evaluated in the field in two cropping seasons at two locations (Agharho and Uyo) of Nigeria for their reaction to African cassava mosaic disease (ACMD) using visual injury score as the index for resistance. Combined analyses of variance for ACMD and fresh tuberous root yield showed significant (P<0.05) sums of squares for genotypes, environments and G x E interaction. The highest fresh tuberous root yield values of 28.8, 27. 0 and 25.7 t/ha were produced by 82/00058, TMS 30572 and TMS 50395, respectively, at 12 months after planting. Lowest indices for ACMD were recor ded at Uyo and were significantly different from Agharho indices. TMS 82/00959, 82/00058, TMS 30572 a nd TMS 50395 showed resistance to ACMD. There was significant negative correlation between ACMD and fresh tuberous root yield. Thus, there is a need to intensify efforts in making available ACMD resistant genotypes to the farmers in this agro-ecological zone.

Keywords: Cassava, Cassava Mosaic, Rainforest Agro ecological  Zone