B.FakrudinAyyanagouda.M.Patil2016-11-022016-11-022009http://krishikosh.egranth.ac.in/handle/1/83523Recombinant inbred lines derived from the cross IS22380 (susceptible) and E36-1 (resistant) were characterized for the morphological and biochemical components of charcoal rot resistance and yield related traits at three locations over four rabi seasons revealed significant differences among RILs and GxE interactions. A significant association among relevant traits was noticed at phenotypic and genotypic level with high heritability estimates. A total of 141 polymorphic DNA markers (48/275 SSRs, 65/533 EST-SSRs, 28/410 RAPD) were genotyped to construct a genetic linkage map spanning 2905 cM and used for Composite Interval Mapping of QTLs. Stable QTLs were detected lodging percent (xtxp176– xtxp312 (CR1) number of internodes crossed by the fungus (xtxp297-xiabt273 (CR2) and length of infection (xtxp275-xtxp241(CR3): the additive effect at all these loci was contributed by E36-1. Two major QTLs of plant height and three QTLs of plant yield accounted for 38% and 41% phenotypic variance respectively. On LG-I, the genomic region flanked by xtxp274–xiabt29 harbored a common QTL. Three stable QTLs, CR1, CR2 and CR3 collectively contributing 43% of phenotypic variation were introgressed into M35-1 and SPV86 backgrounds: at BC1F1 with 2285 and 2033 marker and at BC2F1 5989 and 6002 marker points in M35-1 and SPV86 backgrounds were screened to identify progenies harboring all the three QTLs. Expressional quantitation of 185 transcription factor genes was done in charcoal rot challenged and control tissue of E36-1 and SPV86 genotypes at 75 DAS and 90 DAS where 142 genes up regulated in both genotypes while eight genes of five family viz., AP2 (PTSb00019.1, PTSb00022.1, PTSb00024.1 WRKY (PTSb00331.1), HMG (PTSb00179.1, PTSb00185.1) ARF (PTSb00033.1) and bHLH (PTSb00349.1) were up regulated in pathogen challenged tissues. Two genes of WRKY family (PTSb00328.1 and PTSb00331.1) were significantly up regulated in resistant genotype alone: these understandings would help in developing strategies for resistance breeding in sorghum.Plant BiotechnologyThesis