Genotypic characterization of Pigeonpea (Cajanus cajan) genotypes using molecular markers

Genetic diversity of 42 pigaonpea genotypes was evaluated using 10 RAPD and 10 ISSR markers. Among these, RAPD primers generated 40 bands, out of which 37 were polymorphic and ISSR primers produced 56 bands, out of which 50 were polymorphic. RAPD primers detected more polymorphic loci (92.5%) than the ISSR primers (89.3%). Mean PIC for each of these marker systems (0.86 for RAPD and 0.71 for ISSR), indicated better PIC value of the RAPD markers. Comparison of resolving power of two marker systems (2.15 for RAPD and 4.48 for ISSR), showed better resolving power of the ISSR markers. Based upon Jaccard's similarity coefficient and cluster analysis using UPGMA of both RAPD and ISSR primers, pigeonpea genotypes ‘AL-201’, ‘UPAS-120’, ‘ICP-9174’, ‘ICP10957’ & ‘ICPL-88034’ were found to be quite distinct and can be used for their desirable characteristics in breeding programmes. Dendograms generated using RAPD and ISSR data were comparable with minor clustering differences, which suggests that either a method, or combination of both can be applied to expanded genetic diversity studies in Pigeonpea (Cajanus cajan) and identify variation within genotypes.