Components of Genetic Variation for Yield Traits in Crosses of Indian Mustard [Brassica juncea (L.) Czern. & Coss.]

A field experiment comprising of 4 F₁s, derived from crossing of contrasting parents for the characters viz., plant height, primary branches/plant, siliqua/plant_{, seeds siliquae, test weight and seed yield/plant and their 4F2s, 4B1s and 4B2s was carried to study the genetic variability and inheritance of the yield attributing traits during rabi season in a non-replicated, compact family block design. A high coefficient of variation was observed in the F2 of all the crosses, especially for yield/plant and number of siliqua/plant. Higher narrow sense heritability estimates were recorded for seed yield/plant followed by plant height and siliqua/plant in all the four crosses while number of primary branches/plant and seeds/siliquae showed low heritability. Genetic advance as percentage of mean was high for seed yield/plant and siliqua/plant in most of the crosses. Selection for high number of siliqua/plant is expected to be the crucial selection criteria for yield improvement. Component of additive genetic variation for traits viz., plant height, primary branches/plant, siliqua/plant and seed yield/plant in cross QM-2 x Pusa Barani was highest in magnitude compared to other three crosses for these traits. Importance of additive gene action was revealed in the inheritance of most of the characters under study.}