Efficiency of DNA Marker Systems in Discriminating Cajanus cajan (L.) Millsp. and its Wild Relatives

Two multilocus markers, viz., RAPD (25 primers), ISSR (11 primers) and one single locus marker, viz., SSR (10 primer pairs) were used to assess the genetic diversity among 32 genotypes of pigeonpea and to find the efficient marker system to discriminate the genotypes at molecular level. Diversity analysis was done with the help of statistics such as marker index, mean marker index, polymorphism information content, principal component analysis and dendrogram. The random primers, viz., OPG06, OPG15, OPG03 and the ISSR primers, viz., UBC842, UBC876, and UBC857 are considered to be efficient in discriminating the genotypes. The RAPD, ISSR and SSR markers clustered the genotypes into 10, 12 and 7 clusters, respectively. Among the three marker systems used for the analysis, ISSR markers revealed a higher amount of divergence among the genotypes by producing 215 markers, 99.53 per cent polymorphism, and an average of 19.54 markers than SSR and RAPD. The present study clearly elucidated the superiority of ISSR markers for genetic diversity studies over RAPD and SSR markers.