Selection parameters for grain yield and its components in bread wheat (Triticum aestivum L.)

Wheat (Triticum aestivum L.), a cereal grass of Graminae (Poaceae) family and of the genus Triticum, is the world’s largest cereal crop. Selection parameters in bread wheat were studied in 28 F1s developed by crossing of 8 genotype viz., HD 3171, WH 147, K-906, K 307, K 1006, K 7903, DBW 14 and PBW 502 in half diallel design to study the twelve quantitative characters. The analysis of variance revealed highly significant differences among the genotypes for all the 12 characters. In this study the high heritability (narrow sense) were recorded for plant height, days to maturity & number of spikelets per spike while moderate heritability were found for days to heading, tillers per plant & 1000 grain weight, whereas grains per spike showed low heritability. The estimate of genetic advance in percentage over mean ranged from 3.30 (biological yield per plant) to 32.90 (grain yield per plant) in Fl generation. In F1 generation in general, genotypic correlation coefficients were higher than the corresponding phenotypic correlation coefficient except number of grains per spike, suggesting therefore, a strong inherent relationship in different pairs of characters in wheat genotype. The most important character grain yield per plant had exhibited highly significant and positive phenotypic correlation with biological yield per plant (0.850), spike length (0.490), number of spikelets per spike (0.444) and plant height (0.442). The Path coefficient analysis was carried out at phenotypic and genotypic level to resolve direct and indirect effect of eleven characters on grain yield per plant.