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.
Description:
A Thesis
Submitted to the Faculty of Agriculture,
Sher-e-Bangla Agricultural University, Dhaka
in partial fulfillment of the requirements
for the degree of
MASTER OF SCIENCE
IN
GENETICS AND PLANT BREEDING