Screening of Cowpea Varieties for Cercospora Leaf Spot

An experiment was carried out at two diferent locations (Yola and Mubi, Nigeria) to screen twelve (12) cowpea varieties for their reaction to infection by cercospora leaf spot (Cercospora canescens Ellis and Martin) disease on the field during the 2011 cropping season. The cowpea varieties tested in the study were SAMPEA-1, SAMPEA-2, SAMPEA-4, SAMPEA-5, SAMPEA-6, IFE-BROWN, SAMPEA-7, SAMPEA-8, SAMPEA-9, SAMPEA-10, SAMPEA-11 and SAMPEA-12. The incidence (%) of cercospora leaf spot was observed in both locations at varying levels with all the varieties having the incidence of 100% at 9 WAS at Yola, while SAMPEA-2, SAMPEA-10 and SAMPEA-12 had the highest incidence of 93.33-100% at 9 WAS in Mubi. The severity of the disease was also observed to be higher in Yola than Mubi, where a warm weather coupled with high relative humidity was recorded. At the peak of the disease severity (12 WAS), SAMPEA-2 gave the highest severity in Yola (83.37%), while IFE-BROWN gave the highest severity in Mubi (76.67%). From this study, it was observed that all the 12 varieties tested were susceptible to cercospora leaf spot disease, but some were tolerant to the disease and performed better than others.