Study of Genetic Variability and Yield Component Associations in Indian Mustard (Brassica juncea L.)

Abstract

Understanding genetic diversity within rapeseed–mustard is crucial for strengthening breeding programs aimed at improving yield, stress tolerance, and seed quality. The present investigation was conducted to assess genetic variability and inter-relationships among yield and its component traits in Indian mustard (Brassica juncea L.). The experiment was conducted during the rabi season of 2023–24 at the research farm of J.V. College, Baraut, Baghpat (U.P.), which has clay-loam soil, annual rainfall ranging from 750 to 1190 mm, and temperature variation between 15°C and 30°C. Thirty mustard genotypes were evaluated in a randomised block design with appropriate replications. Observations were recorded on five randomly selected plants perreplication for twelve agro-morphological traits, including flowering and maturity duration, plant height, branching pattern, siliqua traits, seed attributes, biological yield, seed yield, and harvest index. Analysis of variance revealed significant differences among genotypes for most of the traits, indicating the presence of substantial genetic variability. Genotypic and phenotypic coefficients of variation, heritability, genetic advance, correlation, and genetic divergence were estimated using standard statistical procedures. Higher estimates of variability, heritability, and genetic advance were observed for yield and its related traits, suggesting good scope for selection. Correlation and divergence analyses identified important yield-contributing characters, which can be effectively utilised in mustard breeding programs aimed at yield improvement. Overall, the study highlights that traits such as seed yield, biological yield, number of branches, and flowering time can be effectively improved through selection. The identified superior genotypes can be strategically utilised as parents in breeding programmes to develop high-yielding, early-maturing, and agronomically desirable mustard varieties.