H.L.NadafAddissu Gebre2016-11-022016-11-022009http://krishikosh.egranth.ac.in/handle/1/83460The stay-green trait reported component of tolerance to terminal drought stress in sorghum. To map quantitative trait loci (QTLs) for stay-green and other drought tolerance related traits two recombinant inbred populations(RIPs) of F8 lines developed from the crosses IS9830 x E36-1 (RIP I) and N13 x E36-1 (RIP II) were used. The stay-green source line was E36-1 while IS9830 and N13 were non-stay-green lines. A total of 530 genic SSR and 75 nuclear SSR were used for parental survey of which 45 polymorphic SSR were identified with using both 6% PAGE and 2.5 agarose gel. From the total 45 polymorphic primers 20 were genotyped across RILs and used for genetic map construction together with 46 anchor primers. The genetic maps of RIP I and RIP II spanned 1559.1 cM and 1608 cM with 66 and 44 markers distributed over 10 linkage groups, respectively. The two RIPs were phenotyped during post-rainy season at Main Agricultural Research Station (MARS), Dharwad. The measures of stay-green were the green leaf area percentage at 15, 30 and 45 days after flowering (%GLA 15, %GLA30 and %GLA45, respectively). The QTLs detected for % GLA15, %GLA30 and %GLA45 days after flowering explained a phenotypic variations of 34.3, 15.8 and 49.1 in RIP I, and 17, 44.1, and 14 percent in RIP II, respectively. Putative QTLs for other drought tolerance related traits viz. plant height; panicle exertion, head length, and grain yield were detected. Estimated broad sense heritability for %GLA15, %GLA30 and %GLA45 amounted to 0.68, 0. 93 and 0.81 in RIP I and 0.67, 0.88, 0.93 in RIP II, respectively. Across the three measures of stay-green, one QTL on linkage group D was common for both RIPs with the stay-green alleles originated from E36-1. The QTLs detected for both population for stay-green and drought tolerance related traits needs validation across year and environment.Plant BiotechnologyThesis