Assessment of genetic diversity in cowpea [Vigna unguiculata (L.) Walp.] germplasm

Abstract

The present investigation was carried out to understand the extent of genetic diversity in sixty-two cowpea(Vigna unguiculata (L.) Walp) genotypes based on eleven quantitative traits. Mahalanobis’s D2 analysis showed thepresence of wide genetic diversity among the 62 genotypes by the formation of 5 clusters irrespective of geographicaldiversity, indicating no parallelism between geographic and genetic diversity. Cluster I had the maximum number ofgenotypes (39) and cluster IV and V had only one genotype. Intra cluster distance analysis revealed that the minimum intracluster distance was observed in the cluster IV and V. The inter-cluster distance (D) was found to be the maximum betweenthe clusters III and IV and the same was minimum between clusters I and V. A wider genetic diversity was observed for thedifferent traits studied among the genotypes as evidenced by the formation of five clusters. The results indicated that seedyield per plant (23.59 %) contributed maximum to the total divergence followed by peduncle length (17.29 %), 100 seedweight (15.97 %) and number of pods per plant (10.1 %). The present study identified diverse promising genotypes basedon seed yield and agronomic traits such as IC-257449, GC-3, IC-438362, IC- 257428, KBC-9 and IC-390269 and thesediverse genotypes could be utilized in breeding programme of cowpea to generate better transgressive segregants for yieldand its attributes