Abstract:
A field experiment was conducted during November 2016 to February 2017 to study the genetic variability, correlation, path coefficient analysis and genetic diversity for quantitative traits of twenty soybeans (Glycine max L. merill) genotypes in randomized complete block design with three replications at the research farm of Sher-E-Bangla Agricultural University, Dhaka. Experiment showed significant differences among the genotypes. Phenotypic variance was higher than that of genotypic variance for all the characters. Phenotypic coefficients of variation (PCV) was also close to genotypic coefficients of variation (GCV) for all the characters indicating that environment had influence on the expression of these characters. The high heritability coupled with high genetic advance in percent of mean observed in plant height, leaf breadth at top, leaf per plant, pods per plant, seeds per plant, hundred seed weight and seed yield per plant which would be select for future breeding program. High heritability coupled with low genetic advance in percent of mean was observed in germination percentage, leaf breadth at middle and leaf breadth at top. Germination percentage (0.404), plant height (1.464), leaf breadth at base (0.288), leaf breadth at middle (0.401), leaf breadth at top (0.426), pods per plant 0.908), seeds per plant (0.867), hundred seed weight (0.907) and days to maturity (0.535) showed highly significant and positive correlation with seed yield at genotypic levels revealed that selection based on these traits would ultimately improve the seed yield. Path coefficient analysis revealed that hundred seed weight (0.907) had the highest positive direct effect on seed yield. Hence, thrust has to be given for these characters in future breeding program to improve the yield in soybean. Multivariate analysis based on 13 agronomic characters indicated that the twenty genotypes were grouped into five distant clusters. The inter cluster distance was maximum between cluster I and cluster III (38.541). The highest intra-cluster distance was found in cluster V (4.76). It can be concluded genotypes G7 (ASOMEME), G8 (GMOT-13), G12 (BOSS) from cluster I, G10 (BARI SOYBEAN 5) and G18 (BINA SOYBEAN 3) from cluster III, G14 (BINA SOYBEAN 4), G15 (BINA SOYBEAN 1) and G16 (SOHAGH) from cluster V could be suitable for future hybridization program or in view of seed yield for releasing as soybean verities.
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 (MS)
IN
GENETICS AND PLANT BREEDING
SEMESTER: Jan -June, 2016