Genetic Correlation and Path Coefficient Analysis of Yield Attributing Parameters in Indian Mustard

Abstract

Indian mustard (Brassica juncea L. Czern. & Coss) is a natural amphidiploid which is the greatest pre-dominating crop of oilseed Brassica group. A study was undertaken to estimate the genetic variability, correlation and path coefficient analysis of yield and its contributing traits in 75 mustard genotypes grown in Randomized Block Design with two replications. The analysis of variance was highly significant for all the characters investigated. All thirteen characters were showed higher values of phenotypic coefficients of variation than genotypic coefficients of variation. The higher heritability in broad sense was estimated for all the characters. High value of heritability indicates that it may be due to higher contribution of genotypic components. High heritability coupled with high genetic advance as percent of means were recorded for days to 50% flowering, plant height (cm), number(s) of secondary branches per plant, length of main raceme (cm), siliquae length (cm), seed yield per plant (g), yield per plot (g), harvest index and biological yield that indicated predominance of additive gene action in the inheritance of these traits. The higher direct positive genotypic and phenotypic correlations for the biological yield, numbers of primary branches, numbers of siliquae on main raceme and numbers of secondary branches were documented. Whereas, days to maturity and siliquae length showed direct negative correlations with grain yield. Seventy-five genotypes, included in study were grouped into 6 clusters. The maximum inter cluster D2 value indicated that genotypes of cluster III and IV are not so closely related while the genotypes of cluster I and III are closely related. It is apparent therefore; the genotypes of various clusters differ so significantly with regards to their relative genetic distance as indicated from the high variation of D2 values. This makes it clear that the genotypes included in these clusters have a wide range of genetic diversity and may be used in a mustard hybridization programme to develop higher yielding cultivars.