Varietal screening of newly developed blackgram genotypes against Cercospora Leaf Spot (Cercospora canescens) in the Terai region of Nepal.

Abstract

Screening of 12 blackgram genotypes against Cercospora Leaf Spot (Cercospora canescens) was carried out in RCB design with 3 replications in research plot of Mid-West Academy and Research Institute, Tulsipur, Dang during Bhadra to Mangsir, 2078 B.S where the climate is similar to all other Terai region of Nepal. The blackgram genotypes were brought from Grain Legumes Research Program, Khajura, Banke. Disease severity was taken 3 times at 40, 47, and 54 days after sowing. Disease scoring was done as a percentage of leaf area infected on the individual plant at 7-day intervals and disease incidence, disease severity, mean AUDPC, and mean yield was calculated. Disease incidence was not significant among the tested genotypes. Disease severity at 40, 47, and 54 DAS was highly significant among the genotypes. Mean disease score and mean area under disease progressive curve (AUDPC) were also highly significant. Among the genotypes, 10 genotypes were categorized as moderately resistant and 2 genotypes (BLG 0066-1-1 and BLG 0035-1) were categorized as moderately susceptible. The highest Mean AUDPC value (324.1) was possessed by BLG 0035-1 followed by BLG 0066-1-1 (317.6). The lowest mean AUDPC value (175) was possessed by BLG 0069-1. A highly significant difference was found in yield among the black gram genotypes. The highest yield (799 kg/ha) by obtained by BLG 0068-2 followed by Rampur mas (769 kg/ha). The lowest yield (495 kg/ha) was obtained by BLG 0066-1.