Studies on Biodiversity in Grain Cowpea [Vigna unguiculata (L.) Walp.]

Sixty five genotypes of grain cowpea(Source: International Institute of Tropical Agriculture, Nigeria) were evaluated for thirteen metric characters to observe the genetic diversity existing among them by Mahalanobis D² statistics. Out of sixty five, only sixty three genotypes responded towards flowering, on which further study was taken out. The analysis of variance revealed significant differences among the genotypes for each character under study. These sixty three genotypes were grouped into twenty four clusters and the maximum intra-cluster distance was observed in cluster VIII. The maximum inter cluster distance was recorded between cluster XVII and XXII. Based on the cluster means and cluster distances the genotypes EC 517122 (cluster X) and EC 517123 (cluster XXII) were found the most promising. Among the traits studied, days to first flowering and number of pods per plant contributed towards maximum divergence.