SwatiSisodiya, Simran2022-01-192022-01-192021-12https://krishikosh.egranth.ac.in/handle/1/5810181038The research entitled “Assessment of Genetic Diversity in Barley (Hordeum vulgare L.) accessions based on some morpho-physiological traits” comprised of 130 genotypes (126 germplasm lines + 4 checks) planted in Augmented Block Design at N. E. Borlaug Crop Research Centre, G. B. Pant University of Agriculture and Technology, Pantnagar during Rabi 2020-21. Observations were recorded for sixteen traits viz. days to 75% heading, days to 75% maturity, plant height, peduncle length, spike length, number of tillers per meter, number of grains per spike, grain weight per spike, 1000-grain weight, grain yield per plot, biological yield per plot, harvest index, chlorophyll content at anthesis, chlorophyll content at 15 DAA, NDVI at anthesis and NDVI at 15 DAA. The data was analyzed for variance, variability, heritability, genetic advance and clustering of genotypes in different groups. The analysis of variance displayed significant differences among entries for most of the characters, which depicted the existence of ample amount of genetic variability among the experimental material. Variance (mean sum of square) was found to be highest for biological yield and lowest for NDVI at anthesis and 15 DAA. The coefficient of variability was found to be highest for number of grains per spike and lowest for days to maturity. Observations recorded for analyzing genetic variability parameters revealed that the magnitudes of PCV were greater than those of GCV and ECV for all the traits under study. This indicated that the expression for these traits was least affected by the environment. The highest values for PCV along with GCV were observed for number of grains per spike and number of tillers per meter. High heritability coupled with high genetic advance (GA) were reported for number of grains per spike which depicts the presence of additive gene action in the expression of the trait. High PCV and GCV coupled with high heritability expedite the effective selection for these quantitative traits based on phenotypic performance of genotypes. The genotypes were grouped into 9 distinct clusters by non-Hierarchical Euclidean cluster analysis. This indicated existence of genetic diversity in the genotypes evaluated. The maximum number of genotypes (30) was included in cluster-IV followed by 22 genotypes each in cluster-I and cluster-V, cluster-IX included 21 genotypes, cluster-VI comprised of 12 genotypes, cluster-II had 8 genotypes, cluster-VII and cluster-VIII included 6 genotypes each whereas cluster-III had lowest number of genotypes(3). The intracluster distance ranged from 31.787 (cluster-VIII) to 10.466 (cluster-II). The maximum inter cluster distance (60.483) was found between cluster-III and cluster-IV, whereas minimum distance (23.282) was found between cluster-I and cluster-II. Preliminary screening for degree of resistance for Pre-harvest sprouting grouped the 130 barley lines into distinct groups. 44 genotypes were concentrated in grade scale 1 showing resistance towards PHS as they showed no visible in-ear sprouting, while 13 genotypes were grouped in grade scale 7-9 showing high susceptibility with visible sprouting in approximately more than 60% of kernels. Frequency distribution of sprouting index revealed that the lines were commonly skewed with the peak positioned over the highly resistant portion of the distribution thus, indicating that most of the genotypes were resistant to pre harvest sprouting. On the basis of findings of the study, five desirable donors for each character were identified on the basis of character mean. CANELA//LIMON/BICHY2000- 15, CANELA//LIMON/BICHY2000- 16, LACEY/ATILIR, MSEL/CANELA-2 and BLLU/6/P.STO/3/LBIRAN/UNA80//LIGNEE640/4/BLLU/5/ PETUNIA 1 – 2 were found to be most promising donor genotypes for grain yield. These genotypes can be used in future breeding programmes to improve the yield potential of the variety For other characters, genotypes can be picked up from different groups, formed on the basis of their ranking.EnglishThesis