Analysis of genetic variability and path coefficient for yield and yield contributing traits in cultivated and synthetic wheat and their interspecific crosses

Wheat is one of the most important cereal crops in the world grown in diversified environments. The present study aim to assess genetic variation, broad sense heritability and expected genetic advance. Forty wheat genotypes grown in fully irrigated condition at Research Farm, College of Agriculture, Gwalior, during Rabi season of 2013-14. Triticum aestivum varieties viz., LOK-1, Dl-788-2 and Triticum durum variety RAJ-1555 and HI-8627 were significantly superior for grain yield along with harvest index and more traits. Among synthetic varieties SYNTHETIC-1, 3, 4, 5, 7, 10, 11, 12, 13, 14, 15 and 20 recorded high mean performance for grain yield and one or more yield components. High genotypic co-efficient of variation was recorded for harvest index, test weight and biological yield per plant and low for grain yield per plant, days to heading and days to maturity. Phenotypic variances were higher than the genotypic variances. High heritability with low genetic advance in per cent of mean was noticed for days to heading and days to maturity which indicated the involvement of non-additive gene action for the expression of these characters and selection for such trait might not be rewarding. High heritability with high genetic advance in per cent of mean was observed for ear length per plant and tillers per plant indicating that these traits were under control of additive gene action and selection for genetic improvement for these traits would be effective. Grain yield had high positive and significant correlation with harvest index and negative with biological yield. Genotypic correlation coefficients were higher than the corresponding phenotypic correlation coefficients in most of the traits. Path coefficient analysis revealed maximum direct contribution towards grain yield with days to heading whereas phenotypic path coefficient analysis revealed that harvest index showed highest positive direct effect on grain yield.