FATTY ACID COMPOSITIONS ANALYSIS OF F1 POPULATIONS DERIVED FROM 7X7 HALF DIALLEL CROSS IN MUSTARD (Brassica juncea L.)

Abstract

The study was conducted to evaluate the 21 F 1 hybrids of Indian mustard (Brassica juncea L.) for yield and eleven yield attributes and fatty acid compositions. The seven parents including one canola grade genotype were mated in rabi season 2019-20 to develop 21 F 1

hybrids. These F 1 lines and their parents were used to estimate the genetic variability, combining ability, heterosis and fatty acid compositions at Sher-e-Bangla Agricultural University during rabi season 2020-21 in a randomized complete block design with three replications. High heritability in broad sense was observed for all the traits except days to siliqua maturity, siliqua length (cm) and seeds per siliqua; suggested that major proportions of total variance was due to high genotypic effects. Higher σ 2 gca than σ 2 sca was found in days to first flowering, 50% flowering, plant height and harvest index indicating additive genetic effects were predominant for these traits. Furthermore, days to siliqua maturity (51.02%) of the F 1 lines displayed high narrow sense heritability; and plant height (46.28%), days to first flowering (42.52%) and seeds per siliqua (33.56%) showed moderate narrow sense heritability. The parental lines P1, P3 and P4 were found as the best general combiner for earliness and dwarfness. For yield contributing traits, the parents, P2 and P7 showed the best combiner genotypes. Among the cross combinations, the hybrids G3, G7, G11 and G13 indicated the best specific combiners for yield and yield attributes. While the crosses, G4, G6, G17 and G21 found for early maturity and short stature trait. The hybrid G3 followed by G5 and G17 manifested the highest heterosis for early maturity over both the better parent and check variety BARI sharisha-11. In case of plant height, the hybrids G4, G14 and G21 whereas hybrid G7 followed by G1, G11 and G13 manifested the highest desirable heterobeltiosis and standard heterosis for yield and yield related traits. In the fatty acid compositions analysis, the parent P6 had the lowest erucic acid (0.81%); while the cross combination G19-S4 (22.14%) and G5-S1 (22.19%) contained low erucic acid. In hybrids, total saturated fatty acid (TSFA) ranged from 10.81% (G5-S1) to 16.53% (G20-S1), whereas mono unsaturated fatty acid (MUFA) was ranged from 40.60% (G20S2) to 59.18% (G5-S1). The ratio of oleic acid (ω-9) to linoleic (ω-6) acid was found the

highest

in P6 (1.70) followed by G5-S1 (1.19). Moreover, P6 (4.21) showed the highest ratio of linoleic (ω-6) to linolenic (ω-3) acid followed by G19-S4 (3.58). Considering the altogether, the hybrids viz., G4, G5, G7, G11, G17, G19 and G21 were selected and these lines could be utilized further to develop early matured and high yielding having low erucic acid, but higher ω-9, ω-6 and ω-3 fatty acids containing improved variety.