Assessment of the genetic diversity in a germplasm collection of cowpea (Vigna unguiculata (L.) Walp.) using morphological traits

Abstract

Cowpea is considered a minor crop with generally low grain yield; nevertheless production area is spread all around the world, mainly in marginal areas with poor soil and limited rainfall. It is a multipurpose crop grown for green pods as vegetable, dry seeds as pulse and green fodder. The aim of this study was to evaluate 48 accessions of cowpea by 24 morphological descriptors in order to identify accessions with specific behaviour that could be exploited by plant breeders. The accessions with best performance for the development of new varieties and more interesting for inclusion in cowpea breeding programme are 87-052, 95-017, A4E007 and 98210005.  The descriptors pod length, number of seeds per pod, seed thickness and 100 seed weight were found the most stable traits over the three years.   Key words: Cowpea, Vigna unguiculata, landraces, breeding lines, genetic resources, morphological diversity.