EVALUATION OF 15 POPULATIONS OF Brassica rapa L. BASED ON MORPHOLOGICAL AND BIOCHEMICAL TRAITS

Abstract

The investigation was started with the selection process of potential populations of Brassica rapa L. After a continuous process of selection from various lines of these populations the present investigation was carried out under field conditions to evaluate morphological and biochemical traits of the selected populations. The research was based on the evaluation of 15 advanced lines received from the Department of Genetics and Plant Breeding, Sher-e-Bangla Agricultural University, Dhaka, considering 10 agro-morphological and 7 biochemical traits, using randomized complete block design with three replications during rabi season from November 2016 to February 2017 in research farm of Sher-e-Bangla Agricultural University. The analysis of variance showed significant variation in all the traits except number of secondary branches per plant, length of siliqua and thousand seed weight. The phenotypic variances were lower than genotypic variances with little differences in all traits except days to 50% flowering, days to 80% maturity, plant height, number of sliliquae per plant, number of seeds per siliqua and yield per plant. High heritability coupled with high genetic advance was found in number of primary branches per plant, number of secondary branches per plant, number of seeds per siliqua, thousand seed weight and yield per plant. The correlation studies revealed that yield per plant had highly significant positive relation with number of primary branches per plant, number of siliquae per plant, number of seeds per siliqua. Path analysis showed that siliquae per plant had highly significant and positive direct effect on the yield per plant. Biochemical analysis of various fatty acids of seven populations was done. Among the populations lowest amount of palmitic, stearic and erucic acid was found in P3 (1.98%), P4 (0.80%) and P10 (50.21%) respectively. The highest amount of oleic, linoleic and linolenic acid was found in P15 (17.27%), P14 (15.40%) and P10 (9.48%) respectively. In case of short duration P2 (80.67 days) and P14 (78.67 days) showed the lowest result comparing with the two check varieties BARI 15 (84 days) and Tori-7 (82 days). Higher yield/plant was found in P7 (9.77 g), P8 (9.57 g), P12 (13.48 g) and P14 (14.00 g) comparing with the check varieties BARI 15 (8.45) and Tori-7 (6.82). Among the populations P14 was found as the best lines comparing with the checks on the basis of days to 80% maturity, number of secondary branches/plant, number of siliquae/plant, yield/plant, and linoleic acid. By comparing, it might be concluded that populations P1, P2, P7, P8, P10, P12 and P14 had potential for improvement based on the genetic merit of yield and yield contributing factors.