Dhanda, S.S.Duong thi Lan Oanh2018-01-252018-01-252017http://krishikosh.egranth.ac.in/handle/1/5810039843The present investigation was conducted to determine genetic diversity among the recombinant inbred lines for agronomical traits and Karnal bunt resistance in bread wheat. The experiment was conducted during crop season 2013-14 using 95 recombinant inbred lines (RILs) derived from genotypes H567 (Karnal bunt resistant) and WH 542 (Karnal bunt susceptible).The RILs along with their parents were evaluated for Karnal bunt disease infection, agronomic traits, namely, plant height, number of tiller/plant, days to flowering, day of maturity, ear length, number of spikelets/ spike, number of grain/spike, 1000-grain weight, grain yield per plant, biomass/plant, harvest index and quality parameters, namely, hectoliter weight, protein content, gluten content and sedimentation value. The experimental material was evaluated in randomized complete block design with three replications with a plot size of 1 rows of 3 m length. The results showed that coefficient of infection (CI) for Karnal bunt was the range from 0.00 to 17.8 %. Total of 71 RILs were highly resistant (0.00% infection), 9 were resistant (0-5%) infection and remaining were in the susceptible category. The mean squares due to genotypes indicated sufficient variation among the RILs for all the traits. High phenotypic coefficient of variation, high heritability and genetic advance was observed for grain yield and biomass/ plant, while, moderate phenotypic coefficient of variation, heritability and genetic advance was observed for grains/ spike. The phenotypic correlation coefficients of grain yield per plant were significant positive for tillers per plant, 1000-grain weight, number of grain/ spike, spike length, spikelet‟s/ spike, biomass per plant, harvest index and negative with days to 50% heading. Principal component analysis showed that six factors were found significant to explain cumulatively 92.5% variation. The PC-1 was associated with number of grain per spike, spike length and spikelet per spike. PC-2 showed a strong and positive association with grain yield per plant, gluten content and harvest index. The diversity analysis revealed considerable divergence among the RILs. The RIL number 78, 69 and 76 were better for the grain yield and its components, while the RILs numbers 82, 81, 80, and 89 had high expression for other agronomic traits.ennullThesis