Kuldeep Goswami, Mukesh Kumar, L.K. Gangwar, Manoj Kumar Yadav and Hitesh Kumar
Abstract
Genetic variability and character association studies are fundamental for identifying efficient selection criteria in crop improvement programmes. The present investigation was undertaken to assess genetic variability, characterize genotypic and phenotypic associations, and determine the direct and indirect effects of yield-attributing traits in Indian mustard (Brassica juncea L.). 42 diverse genotypes were evaluated during the Rabi season of 2024â25 in a randomized block design with three replications at the Crop Research Centre, Sardar Vallabhbhai Patel University of Agriculture and Technology, Meerut, India. Analysis of variance revealed highly significant differences among genotypes for all fifteen quantitative traits, indicating substantial genetic variability. Grain yield per plant exhibited the highest genotypic (22.16%) and phenotypic (22.76%) coefficients of variation and was associated with high heritability (94.74%) and genetic advance as per cent of mean (44.42%), suggesting the predominance of additive gene action. Grain yield per plant showed strong positive genotypic and phenotypic correlations with biological yield per plant, harvest index, number of seeds per siliqua, 1000-seed weight, siliqua length and number of secondary branches per plant. Path coefficient analysis further identified harvest index and biological yield per plant as the major direct contributors to grain yield at both genotypic and phenotypic levels, followed by number of seeds per siliqua. The findings indicate that simultaneous selection for biological yield per plant, harvest index and number of seeds per siliqua would be an effective strategy for improving grain yield in Indian mustard breeding programmes.