D2 Analysis in Indian Mustard (Brassica Juncea)

Abstract

The present investigation entitled "Studies on 02 analysis in mustard (Brassica juncea)" involving thirty four genotypes was undertaken to examine the genetic variability, heritability, genetic advance, correlation coefficient, path coefficient analysis and genetic divergence. All the thirty four mustard genotypes were tested in randomized block design with 3 replications during rabi 2013-14. Observations were recorded for days to 50% flowering, days to maturity, plant height, number of primary branches per plant, number of secondary branches per plant, number of siliquae on main raceme, length of main raceme, number of seed per siliquae, number of siliquae per plant, 1 000-seed weight, biological yield per plant, harvest index, oil content and seed yield per plant. Analysis of variance exhibited substantial amount of variability among the genotypes for all the characters under study, indicated wide spectrum of variability among the genotypes. High heritability coupled with high genetic advance were observed for plant height, number of siliquae on main raceme, number of seeds per siliquae, number of siliquae per plant, 1 000-seed weight, biological yield per plant, harvest index and seed yield per plant, indicating the preponderance of additive gene effects for these characters and hence may prove useful for effective selection. Seed yield per plant exhibited significant stable and positive association with days to 50% flowering, number of secondary branches per plant, length of main raceme, number of siliquae per plant, biological yield per plant, harvest index and oil content at genotypic and phenotypic level. This indicates that these characters are useful to the breeders in selecting suitable plant type. Biological yield per plant displayed high order of direct effect on seed yield per plant followed by harvest index, number of siliquae on main raceme, number of siliquae per plant, number of secondary branches per plant and number of seeds per siliquae, suggested that can be considered as guidelines for further breeding work. Genotype from the same geographical region fell into different clusters and vice-versa. This suggested that selections of parents for hybridization should be on genetic diversity rather than on the geographical areas. The percent contribution of number of secondary branches per plant followed by length of main raceme, number of siliquae per plant, seed yield per plant, 1 000-seed weight, number of siliquae on main raceme, harvest index and biological yield per plant contributed most towards genetic divergence. Divergence study suggested that crosses suggesting genotypes like Bhavani, Mathura Rai, Ashirvad, Varona, Maya, CS54, Vardan, Jaggannath. RRCDR2 and Pitambari for getting desired segregants from breeding point of view.