Breeding cowpea for resistance to striga gesnerioides in the Nigerian dry savannas using marker-assisted selection

Abstract

Historically, conventional breeding has been the primary strategy used to develop a number of Striga-resistant varieties currently grown in the Sahel of Western Africa. In this study, we have successfully developed and applied a marker-assisted selection strategy that employs a single backcross programme to introgress Striga resistance into farmer preferred varieties of cowpea for the Nigeria savannas. In this strategy, we have introduced the Striga resistance gene from the donor parent IT97K-499-35 into an elite farmer preferred cowpea cultivar ‘Borno Brown’. The selected 47 BC1F2 populations confirmed the recombinants with desirable progeny having Striga resistance gene(s). The 28 lines selected in the BC1F2:4 generation with large seed size, brown seed coat colour and carrying marker alleles were evaluated in the field for resistance to Striga resistance. This led to the selection of a number of desirable improved lines that were immune to Striga having local genetic background with higher yield than those of their parents and standard varieties