Genetic diversity, variability and correlation studies of spike characters in bread wheat under boron deficient soil condition

Experiment was carried out in a randomized complete block with 21 wheat genotypes under boron deficient soil condition. Divergence was studied by multivariate analysis using D2 statistics and the genotypes were grouped into different clusters. Genotypes from clusters II vs III and I vs II may be crossed to obtain more variation in the segregation generations. The range, mean, phenotypic and genotypic co-efficient of variations, heritability, genetic advance and path coefficient were estimated for the characters like, Spike length (cm), Spikelets/ spike, Grains/ spike, Chaffy grains (%), 1000 Grain weight (g), Harvest Index and Yield/ plant (g). The PCV were slightly higher than GCV indicating little influence of environment on the expression of characters under study. Selection for grain yield/ plants and the spike characters such as grains/ spike, chaffy grain (%) and harvest index would be highly effective as these characters exhibited high estimates of heritability and genetic advance. Grain yield/ plant showed significant positive correlation with spike length, number of grains/ spike, 1000 grain weight and harvest index and significant negative correlation with chaffy grain (%) at genotypic and phenotypic levels. The path analysis results showed that spike length, spikelets/ spike, number of grains/ spike, chaffy grain (%), 1000 grain weight and harvest index are the characters which had contributed significantly in increasing the yield/ plant. Hence these characters need to be given importance during selection for improvement of yield under boron deficient soil condition.