Abstract:
The experiment was conducted at the experimental field of Shcr-e-Bangla
Agricultural University. Dhaka under the agro-ceological zone of Modhupur l'ract
(AEZ-28) during January to June of 2011. The experiment was intended to estimate
the nature and magnitude of genetic variability, correlation, path coefficient and
genetic diversity of 39 rice genotypes collected from Bangladesh Rice Research
Institute, Lal Teer Seed Ltd. and Chittagong lull Tracts. All the characters tested
showed significant variations among the genotypes. High genotypic coellicient of
variation was observed for grain yield and number of unfilled grains per panicle.
I ugh heritability coupled with high genetic advance in percent of mean was observed
in grain yield, harvest index. 1000-grains weight, unfiLled grains per panicle.
secondary branches number and plant height indicating additive gene control on the
expression of these characters and that selection based on these characters might be
effective. The significant positive correlations were recorded for number of effective
tillers per plant. 1000-grains weight and harvest index with grain yield at both
genotypic and phenotypie levels indicating that the improvement of these characters
would lead to increase in grain yield. The highest positive direct effect on grain yield
for harvest index followed by number of filled grains indicated that the direct
selection based on these characters would be effective for yield improvement. The
genotypes were grouped into six clusters. Cluster I consisted of the highest II
genotypes from different origin, whereas cluster IV consisted of the lowest three
genotypes. The genotypes of Chittagong llill Tracts were distributed in different
clusters indicated that the geographical distribution was not related to genetic
diversity. The highest inter genotypic distance was observed between Tharak c/han
and BRRI dhan 45 and the lowest between BRRI dhan 33 and BRRI dhan 50. The
highest inter cluster distance was observed between cluster II and Ill and the highest
intra cluster distance for cluster IV. Cluster III had the highest mean values for grain
yield, harvest index. 1000-grains weight and number of effective tillers and cluster V
for number of primary branches and cluster VI for number of tilled grains that had
significant positive correlation with grain yield. Considering all the data analyses, the
genotypes BRRI dhan 36. Gold, BRRI dhan 28, Dowel, BRRI dhan 45, BRRI dhan
50 and indian Pajani could be selected for hybridization program.
Description:
A Thesis
Submitted to the Faculty of Agriculture
Sher-e-Bangla Agricultural University, Dhaka,
in partial fulfilment of the requirements
for the degree of
MASTER OF SCIENCE
IN
GENETICS AND PLANT BREEDING
SEMESTER: July-December, 2010