Genetic analysis and gene mapping of papaya ring spot virus resistance in cucumber

Abstract

The papaya ring spot virus (PRSV) causes significant fruit yield loss in cucurbit crops. Understanding of the inheritance and molecular mapping of PRSV resistance will facilitate development of resistant varieties to control this disease. In the present study, an F2 population was developed from the cross between susceptible ‘65G’ and resistant ‘02245’ cucumber inbred lines. Genetic analysis of PRSV resistance in 144 F2:3-derived F3 families showed that resistance is controlled by a single recessive gene which was designated as prsv02245. Simple sequence repeat (SSR) markers were employed in polymorphism screening between PRSV-susceptible and resistant DNA pools. The PRSV resistance gene, prsv02245, was mapped on chromosome 6 that was flanked by two SSR markers, SSR11-177 and SSR11-1, which was 1.1 and 2.9 cM away from the prsv02245 locus, respectively. The physical distance between the two markers was approximately 600 kb. The accuracy rate of marker-assisted selection of PRSV resistance among 35 cucumber lines using the marker, SSR11-177 was more than 80 %. Results from this study provide a valuable tool for fine mapping, gene cloning, and marker-assisted breeding for PRSV resistance in cucumber.