Assessment of Genetic Diversity in Bread Wheat (Triticum aestivum L.) Germplasm Grown under Rainfed Conditions of Kashmir

Abstract

Assessment of genetic diversity and germplasm improvement is fundamental for sustainable production of different crops including wheat. 200 accessions of wheat germplasm were evaluated during two successive rabi seasons of 2016-17 and 2017-18 along with two national (GW-322 and PBW-343) and one local (HS-240) checks at ICAR-NBPGR RS Srinagar. Principal component and cluster analysis were carried out involving 7 quantitative traits of plant height (cms), flag leaf length (cms), flag leaf width (cms), days to 75% spike emergence, days to 80% maturity, grain yield/plant (g) and 100-seed weight (g). Moderate positive correlations were observed between flag leaf length and days to 80% maturity as well as between these traits and plant height. Days to 80% maturity showed stronger positive correlation with 75% spike emergence which in turn was also strongly correlated with flag leaf length. The results of PCA revealed that the first 4 principal components contributed 76.1% of the total variability with first two components accounting for more than half (51.1%). The divergence analysis based on Euclidian method indicated the presence of adequate genetic diversity with four clusters showing distinct characteristics. 25 promising genotypes identified for each trait, could be useful to plan crosses and study the extent of heterosis