GENETIC DIVERSITY AND CHARACTERS ASSOCIATION ANALYSIS OF ADVANCED LINE OF Brassica napus L.

Abstract

A field experiment was conducted with 26 BC₁F 6 genotypes of Brassica napus L. at the experimental field of Sher-e-Bangla Agricultural University, Dhaka to study the Genetic diversity and characters association analysis of advanced line of Brassica napus during November 2017 to March 2018. The populations were found significantly variable for all the characters. Comparatively phenotypic variances were higher than the genotypic variances for all the characters studied. PCV was higher than the corresponding genotypic coefficient of variation (GCV) for all the traits studied. Higher estimates of PCV than GCV were observed for all the traits. PCV ranged from 1.32% for Days to maturity to 28.46% for Secondary branches per plant and GCV from 0.95% (Days to maturity) to 17.88% (seed yield per plant) The high PCV value was observed for number of secondary branches per plant (28.46%), siliqua per plant (15.43%), 1000 seed weight (13.39%). Seed yield per plant showed high broad base heritability (61.07). The significant positive correlation with seed yield per plant was found with days to flowering (0.319 and 0.070) and siliqua length (0.068 and 0.015). Path coefficient analysis revealed that days to flowering (1.180), plant height (0.009), secondary branches per plant(0.210), number of siliqua per plant (0.493), siliqua length (0.498) and seeds per siliqua (0.005) had the positive direct effect on yield per plant. By genetic divergence analysis Eigen values of principal component axes of coordination of genotypes with the first axes totally accounted for the variation among the genotypes (29.70%) and three PCA account for (61.00%) of the total variation The genotypes were grouped into five clusters. Cluster II contained the large no. of genotypes (11) and cluster III contained only one (1). The cluster V had higher intra cluster distance (2.44) that indicates the highest amount of genetic divergence within the group. The maximum inter cluster distance was observed between genotypes of cluster III and IV (16.453) followed by clusters II and III (11.693). Under cluster III genotypes possessed early maturity, highest plant height, more primary and secondary branches per plant, more siliqua per plant and short siliqua. Considering group distance and other agronomic performance genotypes G1, G2, G13, G15, G18, G19, G21 and G24 might be suggested for future hybridization program.