Estimation of Genetic Component for Quantitative Character in Indian Mustard (Brassica juncea L.) Chaurasia R. K.*, Bhajan Ram G. B. Pant University of Agriculture & Technology, Pantnagar, Uttarakhand *email: chaurasiarameshkumar@gmail.com
Online published on 13 January, 2016. Abstract The present investigation was carried out during 2006–07, 2007–08 and 2008–09 at G.B. Pant University of Agriculture and Technology, Pantnagar. The wide genetic variability was elucidated in the materials for all the 13 characters whereas genetic advance in per cent of mean was found to be high only for 1000-seed weight, number of secondary branches/plant, number of primary branches/plant, length of main raceme and siliquae on main raceme. The seed yield/plant had significant correlation in desirable direction with days to maturity, plant height, siliqua length and 1000-seed weight both at genotypic and phenotypic level. The diallel analysis revealed the importance of both additive and non-additive genetic variance with predominance of latter in the inheritance of days to flowering, days to maturity, plant height, secondary branches/plant, length of main raceme, and seed yield/plant. Components of variation showed that both additive and dominance genetic variation with predominance an important role in the inheritance of days to flowering, days to maturity, plant height, secondary branches/plant, length of main raceme, and seed yield/plant. Significant estimate of H1 and H2 coupled with non significant estimate of D indicated the importance of only non-additive genetic variance for remaining six characters viz., siliquae on main raceme, siliqua length, seeds/silqua, secondary branches/plant, 1000-seed weight and oil content. The ratio of  , which estimates the number of gene groups influencing the characters, with less than one suggested the involvement of one major gene group for all the characters under study except siliquae/plant. The larger magnitude of H1 than H2 for all the characters revealed that the alleles with positive effects and alleles with negative effects at the non-additive loci were in unequal proportion in the parents. The asymmetrical distribution of genes in the parents was evidenced by the value of H2/4H1, which was less than 0.25 in all the cases for 13 characters. Top Keywords Mustard, additive variance, dominance variance, positive genes, negative gene and environment. Top |