SELECTION OF PROMISING LINES BASED ON CHARACTER ASSOCIATION IN Brassica rapa L.

Abstract

A research was conducted by using six F5 and three F8 populations generated through inter-varietal crosses of Brassica rapa L. and grown in the experimental farm of Sher-e-Bangla Agricultural University, Dhaka, during November 2015 to February 2016 to study the variation in different characters, correlation between pairs of different characters and the direct and indirect effects of different traits on yield of the F5 and F8 materials to select high yielding and early mature plants. Considering genetic parameters, comparatively phenotypic variances were higher than genotypic variances for all characters studied. Number of primary branches per plant, number of secondary branches per plant, length of siliqua, number of seed per siliqua, thousand seed weight and yield per plant 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, thousand seed weight and yield per plant. The highest yield per plant (11.95 g) was found in BARI sarisha-6×BARI sarisha-15 S1F5. The advanced line BARI sarisha-6×BARI sarisha-15 S2F8 matured early (80.33 days) and produced moderate yield (4.35 g/ plant). The highest GCV (79.55 %) and PCV (79.62 %) were observed in number of secondary branch per plant. Number of siliqua per plant showed high heritability (96.69%) along with high genetic advance (88.55) and high genetic advance in percentage of mean (73.66%). The highest genetic advance (88.55%) was found for number of siliquae per plant. Moderate heritability (39.30%) with low genetic advance (3.06) was found for days to maturity. Yield per plant had non-significant and positive correlation with days to maturity, plant height, number of secondary branches per plant, number of siliqua per plant, siliqua length and thousand seed weight. The path co-efficient analysis revealed that number of siliqua per plant had the highest positive direct effect followed by number of seed per siliqua, number of secondary branches per plant and days to maturity. Populations of four most promising lines with higher yield were selected from different nine crosses of the F5 and F8 populations of Brassica rapa L.