GENETIC VARIABILITY, CORRELATION AND PATH ANALYSIS IN F5 GENERATION OF Brassica napus L.

Abstract

For meet our own requirements every year we are importing edible oil and spent huge economy. This requirement will be fulfill by developing the high yielding varieties from the local germplasm. The need is to enhance and improve the production of the local cultivars and for that purpose the genetic variability and diversity of the local cultivars must be fully explored. Sixty two F5 population of Brassica napus L. were evaluated through randomized complete block design with two 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 population were found significantly difference for all the traits studied. The maximum plant height and secondary branches per plant was observed by the population G62. Maximum primary branches per plant and siliqua per plant was found in G45. Higher estimates of PCV than GCV were observed for all the traits. Maximum GCV and PCV were recorded for number of secondary branches per plant (37.15 and 29.48). Broad sense heritability values were higher (more than 61%) for all the traits and it ranged from 51.62% (1000 seed weight) to 98.80 % (days to maturity). Genetic advance as percent of mean was highest (48.19%) for secondary branches per plant and lowest (8.44%) for days to maturity. The significant positive correlation with seed yield per plant was found with all most of the traits except days to 50% flowering. Path analysis revealed that days to 50% flowering (0.188), days to maturity (0.293), plant height (0.038), primary branches per plant (0.627), number of siliqua per plant (0.614), number of seeds per siliqua (0.362) and 1000 seeds weight (0.397) had positive direct effects on seed yield per plant. By genetic divergence analysis 62 population were grouped into five clusters and maximum population (25) were included into cluster II. The maximum inter cluster distance was observed between population of cluster I and III (14.763) followed by clusters II and III (10.475) and I and V (8.689). On the basis of diversity pattern and agronomic performance population G45 and G62 were found for high yielder, early flowering and bold seeded. Population G2 and G6 were found for early maturity and dwarf plant type. These superior population may be used in future breeding program to develop short duration cultivar of mustard.