Abstract:
Thirty genotypes from BC
1
F
7
populations of Brassica napus L. were evaluated to study
the genetic variability, heritability with genetic advanced, correlation and path analysis
based on yield and yield component traits. The experiment was conducted at the
experimental field of Sher-e-Bangla Agricultural University, Dhaka during midNovember
2018 to mid-March 2019. The experiment was laid out in Randomized
Complete Block Design (RCBD) with three replications. Analysis of variance revealed
significant variations among the genotypes for all the traits studied. Mean difference
studies showed significant values for all the traits among the genotypes. Comparatively
phenotypic variances and PCV (Phenotypic Coefficient of Variation) were higher than the
genotypic variances and GCV (Genotypic Coefficient of Variation) for all the characters
studied. The highest PCV value was observed followed by seed yield per plant (31.20%)
number of secondary branches per plant (25.39%) and 1000 seed weight (21.96%) and
GCV values were followed by seed yield per plant (23.97%), number of secondary
branches per plant (17.68%) and thousand seed weight (12.18%). High heritability values
coupled with high genetic advances as percent of mean was noticed for seed yield per
plant (37.94%) with heritability (59.04%) and secondary branches per plant (25.36%) with
heritability (48.49%). The significant positive correlation with seed yield per plant was
found in primary branches per plant (G=0.297, P=0.283), secondary branches per plant
(G=0.260 P=0.293), siliqua per plan (G=0.589, P=0.489), seeds per siliqua (G=0.325,
P=0.403) and 1000 seed weight (G=0.277, P=0.278). On the other hand, path analysis was
exhibited the positive direct effects towards days to 50 % flowering (5.806), plant height
(cm) (1.838), primary branches (3.067), siliqua length (cm) (0.789), seeds per siliqua
(1.385) and 1000 seed weight (g) (1.102) where negative direct effect was recorded in
days to 1
st
flowering (-5.490), secondary branches per plant (-2.497), siliqua per plant (0.279).
Based on the result of the study, according to seeds yield per plant and other
agronomic performance genotypes G
13
(19.59), G
24
(17.20), G
19
(14.05), G
30
(13.19) and G
29
(15.13) can be used further for varietal improvement programs and
development of higher-yielding variety.
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
