GENETIC VARIABILITY AND CHARACTER ASSOCIATION AMONG YIELD AND ITS CONTRIBUTING TRAITS IN MUSTARD (Brassica napus L.)

Abstract

Mustard (Brassica napus) belongs to the Brassiacaceae family and is the major edible oil producing crop of Bangladesh. The total oilseed production of the country is not sufficient. Therefore, we spent a huge amount of money for importing edible oil which could be minimize through enhancing and improving the existing germplasms. To do this, the genetic variability and diversity of the existing germplasm should be evaluated. Thirty five genotypes of Brassica napus L. were evaluated based on randomized complete block design with three replications at the experimental field of Sher-e-Bangla Agricultural University, Dhaka, to study the variability, correlation, path analysis and genetic diversity during November 2015 to February 2016 growing seasons. The genotypes were found significantly variable for most of the characters. Comparatively phenotypic variances were higher than the genotypic variances for most of the characters studied. The high GCV value was observed for Number of Seed Yield per Plant (28.28). Seed Yield per Plant (99.47) exhibited the highest value of heritability followed by number of Siliquae per Plant (90.35) while Plant Height (17.89) exhibited the lowest value of heritability. The significant positive correlation with Seed Yield per Plant were found in Number of Primary Branches, Siliquae Length, Number of Seed per Plant, Number of Seed per Siliquae and Thousand Seed Weight. Insignificant and negative correlation with seed yield per plant were found in Days to 50% Flowering, Days to Maturity, Length of Main Raceme and Number of Secondary Branches. Insignificant but positive interaction was found for Plant Height with Seed Yield per Plant. Path co-efficient analysis revealed that Days to Maturity, Plant Height, Number of Primary Branch, Siliquae Length, Number of Siliqua per Plant, Number of Seed per Siliqua, and Thousand Seed Weight had the positive direct effect on yield per plant whereas Days to 50% Flowering, Length of Main Raceme and Number of Secondary Branch had the negative direct effect on yield per plant. On the basis of cluster analysis, all the genotypes were classified in four clusters. The highest inter cluster distance was observed between cluster I and IV (15.547). The lowest inter-cluster distance was observed between clusters III and II (2.978). Considering group distance and other agronomic performance genotypes G2, G11 and G24 might be suggested for future breeding program.