GENETIC VARIABILITY, GENOTYPE × ENVIRONMENT INTERACTION AND YIELD STABILITY IN COWPEA GERMPLASM: IMPLICATIONS FOR BREEDING

Abstract

A total of 147 cowpea [Vigna unguiculata (L.) Walp.] germplasm accessions and two checks (C-152 and KBC-9) were evaluated at Bengaluru, Mandya and Pavagada during summer 2022 to assess genetic variability, genotype × environment interaction (GEI) and yield stability. The experiment was conducted using an α-lattice design with two replications per location. Pooled ANOVA revealed highly significant effects of genotypes, environments and GEI for grain yield and associated traits, indicating differential environmental responses. High heritability coupled with high genetic advance was observed for plant height, primary branches, pods per plant, pod length, seeds per pod and grain yield, suggesting additive gene action. K-means clustering grouped genotypes into 12 clusters, with maximum divergence between clusters VI and VII. AMMI and GGE biplot analyses identified KBC-2, IC-237422 and EC-170574 as high-yielding and stable genotypes. Specific adaptation was observed for IC-402159, CB-1024, IC-458492, NBC-51 and EC-472252. Stable genotypes identified through AMMI and stability indices can be utilized in breeding programmes.