Abstract

Seed testa colour is the first morphological lead to the recognition of preferred cowpea varieties. Differences among a population of four segregated lines of a cowpea accession were examined at the CSIR – PGRRI experimental fields during 2010. These four lines descended from cowpea accession Gh4524 and are distinguished based on their grain testa colour. The different grain coat colours were examined in relation to flower colour and immature pod pigmentation. It was observed that definite relationship existed between these traits in the cowpea lines studied. The lines segregated from the original population in the ratio, 9:3:3:1. Heterozygosity decreased by 30% from the S₀ to S₁. The result of the experiment demonstrates that some land races under conservation are mixtures of pure lines. Effort to prevent the loss of genetic diversity in such germplasm is recommended.

Key words: Cowpea, coat colour, heterozygosity, germplasm, pigmentation.