Nuclear-cytoplasmic diversity in parental genotypes used for Indian early bulking potato (Solanum tuberosum ssp. tuberosum) breeding programme

Forty parental lines used for development of early bulking potato varieties were analyzed for genetic divergence using twenty RAPD primers and cytoplasmic base by using six PCR-based markers comprising of two chloroplast DNA deletions based (H1 and H3), one plastid SSR (NTCP9) and three mitochondrial SCAR markers. In RAPD divergence studies there were three clear clusters, those with andigena pedigree and JF series in pedigree formed two separate clusters from rest of genotypes. AGB69.1 was the most distinct parent followed by the parent-progeny combination (MS/82-638 and MS/92-3128). On plastome/chondriome analysis three andigena type cytoplasm possessing parents (Phulwa, AGB69-1 and A98-175) and four wild type cytoplasm possessing parents (i.e. AG14(X37)H, J99-2, A98-165 and PS/M75) were distinct from the rest i.e. tuberosum type cytoplasm genotypes. The diverse andigena type cytoplasm genotypes can be preferred as parents to broaden the genetic base in early bulking varieties, while those wild type cytoplasm genotypes may contribute to introgression of useful traits like higher dry matter and late blight resistance.The results of present study showed that divergent parents from both paternal and maternal pedigree are being used in Indian breeding programme for early bulking varieties. Divergent parents identified in present study may be useful in planning hybridization programme aimed at effective utilization of heterosis.