Identification of RAPD markers linked to plant type gene in pigeonpea.

Pigeonpea is the second most important pulse crop of India accounting for almost 90% of the World’s pigeonpea area and production. Altering the plant types could improve the economic yield and its adaptability as well. Molecular markers can identify and tag plant type genes without much environmental interference. In the present investigation of identifying and tagging RAPD markers linked with the plant type trait, the plant material consisted of parents, F 1 and a F 2 population obtained by crossing genotypes TT44-4 with open-tall and TDI2004-1 with compact-dwarf plant types. RAPD analysis was performed on 84 genotyped F 2 plants following a bulked segregant analysis (BSA) approach. In the parental screening with 200 random decamer primers, only eight showed polymorphism, of which only two could be linked to the plant type gene. Two markers (OPF04 700 and OPA09 1375 ) were identified that were present in the open-tall plants, while absent in compactdwarf plants. Linkage analysis showed that the markers OPF04 700 and OPA09 1375 were located 8.4 ±0.03 cM and 9.6 ±0.032 cM, respectively away from the plant type gene locus. The markers were validated in 15 genotypes with open-tall plant type. The utilization of the marker and the dwarfing gene is discussed.