VARIABILITY STUDY IN EIGHT ADVANCED POPULATIONS OF Brassica rapa L.

Abstract

The present study was undertaken by using eight advanced populations of Brassica rapa L. to study variability among them at the experimental field of Sher-e-Bangla Agricultural University, Dhaka-1207 during November 2018 – February 2019 to evaluate the magnitude of variations in characters, heritability, genetic advance, correlation, direct and indirect effect of different characters on seed yield per plant for twelve characters. Analysis of variance revealed significant variations among all populations for all the traits. Minimum difference between phenotypic and genotypic variance was observed in root length (cm), number of primary branches per plant, number of secondary branches per plant, length of siliqua (cm) and thousand seed weight (g). However, high genotypic and phenotypic coefficient of variation was observed for the characters viz; number of primary branches per plant, number of secondary branches per plant, number of siliquae per plant, seed yield per plant (g). High heritability with low genetic advance was observed in days to first flowering, days to 50% flowering, days to 80% maturity, number of primary branches per plant, number of secondary branches per plant, number of seeds per siliqua, length of siliquae, thousand seed weight and seed yield per plant whereas high heritability with high genetic advance was observed in plant height, number of siliquae per plant. Correlation study revealed that seed yield per plant had a significant positive correlation with number of primary branches per plant, number of secondary branches per plant, root length (cm), number of siliquae per plant, number of seeds per siliqua, length of siliquae (cm) and thousand seed weight (g) at the genotypic and phenotypic level. Direct positive effect on seed yield per plant was found in days to first flowering, plant height (cm), number of siliquae per plant and length of siliquae (cm) through path coefficient analysis. According to their yield and yield contributing characters five advanced populations such as Pop n 3 (BARI Sarisha-6 X BARI Sarisha-15, F 10, 76.667 days), Pop n 4 (SAU Sarisha-1 X BARI Sarisha-15, F 8, ii

78.667 days), Pop n 1 (SAU Sarisha-2 X BARI Sarisha-15, F 8, 80 days), Pop n 6 (SAU Sarisha-1 X BARI Sarisha-15, F 8, 78.667 days) and Pop n 5 (BARI Sarisha-15 X SS 75 (Sonali Sarisha), F 11 , 85.667 days) with higher seed yield per plant were selected from the 8 advanced populations.