Genetic Variability and Association Studies in Germplasm Accessions and Land Races of Wheat (Triticum aestivum L.)

Wheat (Triticum aestivum L.) is described as the ‘King of Cereals’ is a leading cereal crop which plays a crucial role in feeding the hungry world and improving global food security. Understanding the contribution of yield components to the variation of grain yield is essential for designing breeding programs and increasing grain production. A diversity panel of 200 genotypes including 145 accessions and 55 landraces of wheat were evaluated in Augmented Design for genetic variability and correlation between grain yield and yield related components. Analysis of variance revealed significant differences among the genotypes for all the traits except chlorophyll fluorescence. The highest phenotypic coefficient of variation (PCV) and genotypic coefficient of variation (GCV) were recorded for effective number of tillers metre-1 followed by biological yield row-1, flag leaf length, grain yield row-1. Heritability coupled with genetic advance percent of mean was high for effective number of tillers metre-1, followed by biological yield row-1, flag leaf length, grain yield row-1. Association studies revealed a highly significant and positive association of grain yield row-1 with biological yield row-1 (0.805), 1000-grain weight (0.476), effective number of tillers metre-1 (0.328), flag leaf width (0.137) and harvest index (0.133) whereas, it showed a significant negative association with days to maturity (-0.304) and days to 50% heading, (-0.291). The study revealed that days to maturity, days to heading, 1000-grain weight and effective number of tillers metre-1 could be considered the most appropriate traits for improvement and selection of trait to achieve stable and high yielding early wheat genotypes.