Markers for Quantitative Inheritance of Resistance to Foliar Thrips in Cowpea

Molecular assisted breeding is currently constrained by the lack of breeder-friendly trait-associated markers, especially among lesser studied crops. Recent advances in genomic technology are being applied to many important crop species, promoting the development of robust marker-trait associations. Regions of the cowpea [Vigna unguiculata (L.) Walp.] genome controlling the quantitative resistance to feeding by foliar thrips (Thrips tabaci and Frankliniella schultzei) were tagged by coupling phenotypic observations from two recombinant inbred line populations generated from domesticated parents. Three regions (Thr-1, Thr-2, and Thr-3) explaining approximately 32, 24, and 9%, respectively, of the phenotypic variation were tagged with several expressed sequence tag (EST)-derived single nucleotide polymorphism (SNP) markers and are presented here as haplotypes composed of multiple SNP markers. Regions within the soybean [Glycine max (L.) Merr.] genome that are syntenic to cowpea Thr-1, Thr-2, and Thr-3 are also reported.