Abstract:
A study of the attributes for seed yield of 28 F,s and their parents 8 x 8 diallel
(excluding reciprocals) of Brassica juncea L., showed the contribution of both additive
and non-additive components for all traits indicating the importance of both additive and
dominance components. Dominant gene action was predominant in most of the traits
except days to maturity, plant height and 1000-seed weight. Height heritability (76 per
cent) was observed for days to maturity. The asymmetrical distribution of the positive and
negative alleles at all loci was found for all the characters studied. The Vr-Wr graphs
exhibited dominance effect of genes for all the characters. Over dominance was observed
for the traits primary branches per plant, secondary branches per plant, length of siliqua,
siliquae per plant, seeds per siliqua and seed yield per plant while partial dominance was
observed for days to 50%flowering, days to maturity, plant height, 1000-seed weight,
harvest index and oil content. The graphical analysis indicated wide genetic diversity
among the parents.
