Dalal, Mohinder SinghLovneesh2024-07-032024-07-032023-08https://krishikosh.egranth.ac.in/handle/1/5810211399Wheat yield materialization varies greatly due to its interaction with the environment since grain yield in wheat is a polygenic hereditary trait. In perspective of the improvement in yield, the present study entitled “Assessment of genetic variability and diversity in wheat genotypes based on agromorphological descriptors” was conducted at research farm area of Wheat and Barley Section, Department of Genetics and Plant Breeding, CCS Haryana Agricultural University, Hisar during the Rabi season of 2022-23. The main objectives of the study were genetic variability, character association and genetic diversity in fifty wheat genotypes including five checks. The analysis of morpho-physiological traits in genotypes under rainfed and irrigated conditions revealed that PCV was slightly higher than GCV for all the traits indicating a little influence of environment. High heritability along with high genetic advance under both conditions was observed for the traits, viz. CTD 2 followed by CTD 1, number of productive tillers per plant and spike length. Grain yield per plot was significantly and positively correlated with almost all the characters except days to heading under rainfed conditions; and days to heading, days to maturity under irrigated condition. Principal component analysis revealed that six out of eighteen principal components were more important accounting for 71.14% of total variance under rainfed and 67.39% under irrigated conditions. Cluster analysis grouped the genotypes into six clusters under both conditions. Maximum inter-cluster distance was found between cluster I & III in irrigated and cluster II & III in rainfed condition which implies that the genotypes from these clusters can be intercrossed to produce superior varieties for higher grain yield. On the basis of mean performance of different clusters, genotype in cluster IV in irrigated condition and cluster II in rainfed can be used as parent for further improvement of grain yield. Higher grain yield was recorded for the genotype 13HZAN-19 followed by 13HZWYT-404, N3149, P30041, P20102 and 13HZAN-46 in irrigated condition. In rainfed condition genotype P30041, 12HPYT-467, 13HZAN-19 and 13HZWYT-404 had promising grain yield. Therefore, these genotypes can be used for the development of drought resistant varieties in future breeding programmes.EnglishThesis