Brown blotch disease caused by Colletotrichum capsici, is one of the most important disease affecting cowpea production in Burkna Faso. Every year the disease can cause yield losses as high as 42-100% in farmer’s fileds. In order to determine the nature of genes transmission, inheritance of the resistance has been undertaken. Seedlings of parents and F1, F2 and BC1F1 progeny from crosses involving four susceptible and four resistant parents were tested in greenhouse condition. The inheritance studies indicated genes of different nature were implicated in brown blotch resistance. In KN-1 variety, two or several genes associated to brown blotch were suggested. In Donsin local, a partial dominant gene, Rcc1, would be associated to the resistance. In Moussa local, a single major dominant gene, Rcc2, was identified. A single major recessive gene, rcc2, was found to control resistance to brown blotch in the cowpea resistant variety IT93K-503/46-13. The research of gene or QTL associated to brown blotch in cowpea variety KN-1 has been investigated. Polymorphic SNP markers and QTL associated to brown blotch resistance were discovered from 63 F2 individuals from a cross involving the susceptible variety Tiligre and the resistant KN-1. More than 11800 polymorphic SNP markers covered 1019,3 cM of the whole genome of cowpea were identified. A single dominant QTL, nomed qBBDR2.1, and 102 individual SNP markers associated to resistance of C. capsici were identified on chromosome 2 (Phytozome) of the cowpea genome.
Keywords: cowpea, C. capsici, resistance, inheritance, SNP marker, QTL