Genetic studies of genetic variability and trait associations in mustard spp. (Brassica juncea L. & Brassica carinata A.)

Mustard is a widely cultivated oilseed crop in India, known for its high yield potential and suitability for both sole cropping and intercropping. In the rabi season of 2015-16, a study was conducted involving 64 different genotypes and six check varieties using an Alpha lattice design with three replications to assess various yield attributing traits. The findings indicated substantial genotypic and phenotypic coefficient of variation, particularly for traits such as the number of siliqua per plant and grain yield per plant. Traits like siliqua per plant and plant height showed high heritability (>60%) and significant genetic advance as a percentage of the mean (>20%), suggesting the prevalence of additive gene action. Analysis of character association revealed a positive and significant correlation between grain yield and traits like days to maturity, plant height, primary branches per plant, siliqua length, siliqua per plant, and test weight, implying the potential for simultaneous improvement of these traits alongside grain yield. Path coefficient analysis highlighted siliqua per plant as having a high direct positive effect on grain yield, with its correlation coefficient with grain yield nearly equating its direct effect. This underscores the importance of siliqua per plant as a selection criterion for enhancing mustard seed yield, suggesting a focus on this trait for further improvement.