VARIABILITY AND INTERRELATION OF TRAITS IN SEGREGATING GENERATIONS OF RAPESEED (Brassica rapa L.)

Abstract

A research was conducted by using twenty F3 and F4 populations generated through inter-varietal crosses, along with three check variety of Brassica rapa L and grown in the experimental farm of Sher-e-Bangla Agricultural University, Dhaka, during November 2013 to February 2014 to study the variation in different characters, correlation between pairs of different characters and the direct and indirect effect of good yielding plants of the F3 and F4 material to select high yielding and early mature plants. Considering genetic parameters, comparatively phenotypic variances were higher than the genotypic variances for all the characters studied. Days to maturity, number of primary branches per plant, length of siliqua, thousand seed weight showed least difference between genotypic and phenotypic variance. High phenotypic and genotypic co-efficient of variation were found on number of secondary branches per plant, number of siliqua per plant and yield per plant. Thousand seed weight and yield per plant showed high heritability with low genetic advance and high genetic advance in percentage of mean. Yield per plant had significant and the positive correlation with plant height, number of primary branches per plant number of secondary branches per plant, number of siliqua per plant and thousand seed weight. The path co-efficient analysis revealed that plant height had the highest positive direct effect followed by siliquae per plant, number of seed per siliqua, number of secondary branches per plant. Twenty one most promising plants with short duration and higher yield were selected from different five crosses of the F3 and F4 populations of Brassica rapa L.