Genetic diversity analysis in bread wheat (Triticum aestivum Linn. Emend Thell.) for yield and its contributing characters

The present investigation was carried out with 21 diverse genotypes of bread wheat incompletely randomized block design with 3 replications at Krishi Vigyan Kendra, Bilari, Moradabad to assess these released varieties, their 12 quantitative characters viz. days to maturity, plant height (cm), no. of effective tillers/plant, flag leaf length (cm), flag leaf width (cm), flag leaf area (cm²), spike length (cm), no. of grains/spike, biological yield (g), 1000-grain weight (g), harvest index (%) and grain yield/plant (g) for genetic diversity for yield and its contributing traits under normal sown condition. The statistical analysis for genetic divergence was done using Mahalanobis-D²statistics and clustering of genotypes using Euclidean method. On the basis of genetic diversity analysis, it was found that the maximum percent contribution towards genetic divergence was from number of effective tillers per plant and minimum by grain yield per plant. Clustering of genotypes revealed that cluster-III has maximum number of genotypes (07), clusters I and VI each have 04 genotypes, clusters II have 3 genotypes, clusters VI have 2 genotypes while clusters V has only one genotype. The high estintra-cluster distance was shown by cluster-VI (81.607) revealing maximum genetic divergence among its constituents. The highest inter-cluster distance was found between clusters V and VI (548.020) and the lowest was between cluster-II and III (96.157). Cluster-I exhibited highest cluster means for the traits 1000-grain weight and harvest index, Cluster-VI for grain yield per plant, number of grains per spike and biological yield while clusters-II and IV revealed highest cluster means for leaf width and leaf area. The genotypes having desired values from different clusters can be exploited in further breeding programme for the development of high yielding wheat genotypes.