Identification of new sources of rust resistance in COWPEA (Vigna unguiculata L. walp) germplasm using simple sequence repeat markers

Abstract

The demand for resistance cowpea to rust infection has currently increased due to considerable yield losses caused by the fungal pathogen. The study assessed available cowpea genotypes for rust resistance using simple sequence repeat (SSR) markers. Out of 100 cowpea genotypes screened, 97% showed the presence of the markers whilst 3% showed absence of the markers. Among the cowpea were 72% resistance, 16% moderate resistance and 9% low resistance to rust. The markers revealed a mean high allele frequency (0.86) and low gene diversity (0.24) and polymorphism information content (0.21) among the cowpea genotypes. The markers co-inherited with a mean regression value greater than 0.1. There was no clear pattern of clustering among the cowpea genotypes. The cowpea genotypes with rust resistance traits could serve as good sources of germplasm for cultivation or resilient genes with rust target in breeding programmes to improve the crop.