Microsatellite markers linked to sterility mosaic disease resistance in pigeonpea (<i>Cajanus cajan</i> L. Millsp.)

Abstract

Sterility mosaic disease (SMD) is a major viral disease of pigeonpea in southern India. In the present study, simple sequence repeat (SSR) markers were employed to identify those genomic regions associated with resistance to Bengaluru isolate of SMD through bulked segregant analysis (BSA) approach. Eighty four F 6 recombinant inbred lines (RILs) derived from the cross ICP 8863 (susceptible) x BRG 3 (resistant) were used. A total of 50 hypervariable pigeonpea specific SSR primers (AHSSR) were screened for parental polymorphism study. Out of 50 primers surveyed, 40 primers (80%) were found polymorphic between parents. Based on BSA, three SSR markers viz ., AHSSR 50 150 , AHSSR 34 130 and AHSSR 20 125 were successfully differentiated resistant and susceptible bulks, and also showed a clearcut differentiation between resistant and susceptible RIL individuals used for constituting these bulks. Segregation analysis of these three SSR markers on 84 F 6 RILs exhibited expected Mendelian segregation ratio of 1:1. Single marker analysis (SMA) showed that AHSSR 50 150 , AHSSR 34 130 and AHSSR 20 125 were closely associated with SMD resistance and explained 21, 8 and 6 per cent of phenotypic trait variations. The markers identified from this could be useful for SMD resistance breeding in pigeonpea.