Genetic analysis and marker assisted backcrossing for transfer of mosaic virus resistance in cowpea [Vigna unguiculata (L.) Walp.]

Cowpea mosaic virus (CpMV) is known to cause yield loss of as much as 80–100 per cent. Among different approaches available in the management of this disease development and release of resistant varieties is the most viable option for farmers. Hence an investigation was carried out to study the inheritance of resistance to cowpea mosaic virus (CpMV) and to identify DNA markers linked to genomic regions conferring resistance to CpMV. The resistance was found to be governed by single recessivegene inthe 191F_{2: 3} progenies derived from the cross C-152(susceptible) ×V-57817 (resistant). Single marker analysis with 191 F₂ individuals and 106 polymorphic SSR markers indicated that two markers, MA15 and MA80 were linked to CpMV resistance as evidenced by significant mean sum of squares due to between marker classes and putative linkage of these markers for resistance to CpMV was confirmed by bulked segregant analysis. Through linkage map constructed utilizing 91 polymorphic SSR markers it was possible for us to show that the two markers MA15 and MA80 were included in the linkage group 6 and the marker gene was likely to be present between these markers. Marker assisted backcrossing was practiced to transfer resistance gene in to an agronomically superior variety C-152.