physicochemical

ABSTRACTS
interaction was significant for all the characters except
number of branches per plant, pod length, number of
seeds per pod, 100 seed weight, protein content and
harvest index.
None of the genotypes showed stable
performance for all the characters studied according to
Eberhart and Russell (1966) model. Based on stability
parameters L sp 13, MRSB 345, LSb 36 and PK 1029
were found to be stable for days to 50% flowering. While,
JS 335, LSb 13, LSb 36 and RKS 18 were found to be
stable for day to maturity. M.Sc (Ag), 2008
Genetic divergence in soybean (Glycine max (L.) Merrill) genotypes
Student: Pushpa Reni. Y Major Advisor: Dr. Y. Koteshwar Rao
Department of Genetics and Plant Breeding
An investigation was conducted during
Kharif, 2007 at Regional Agricultural Research
Station, Lam Guntur, Andhra Pradesh.
The analysis of variance revealed significant
differences among the genotypes for all the
characters studied. The genotypes coefficient of
variation for all characters studies was lesser than
phenotypic coefficients of variation indicating the
masking effects of the environment. High PCV
coupled with high GCV, observed for branches per
plant pods per plant, biological yield, harvest index
and yield per plant indicate the presence of wider
adaptability for these traits in the genotypes studied.
High heritability coupled with high genetic advance
as presence of mean was observed for days to 50%
flowering plant height, number of branches per plant,
number of pods per plant, pod length, number of
seeds per pod, 100 seed weight, biological yield,
harvest index and seed yield per plant indicating
operation of additive gene action in these traits is
possible through simple selection.
The results of multivariate analysis indicating
the presence of considerable genetic divergence
among the 45 genotypes studied. The 45 genotypes
were grouped into 6 clusters. Clustering pattern of
genotypes did not follow geographical origin,
suggesting that geographical isolation may not be
the only factor causing genetic diversity. Based upon
the divergence studies, crosses may be made
between the genotypes the genotypes of cluster III
(PS 1421) and cluster VI (VLS 69) to be isolate good
recombinants.
Out of 13 characters studied day to maturity
followed by pods per plant contributed maximum
towards divergence. The principal component analysis
identified 5 principal components with eight value
more than one. The contribution by the first (PC 1
) is
maximum and loaded with maximum contributing
variables i.e days to maturity, pods per plant and
days to 50% flowering.
The clustering pattern is in accordance with
the PCA analysis during Kharif, 2007. Hierarchial
cluster analysis revealed the subgroups in the major
group of genotypes through Ward’s minimum variance
dendrogram.
Correlation studies indicating that the seed
yield per plant was positively correlated with,
biological yield per plant (g), number of pods per plant
and harvest index (%). The results of path coefficient
analysis further suggested that selection of the
characters biological yield per plant (g) number of
pods per plant and harvest index (%) will have positive
influence on seed yield per plant. As these characters
exhibits both direct effects and positive correlation
with seed yield. Thus, the present study, revealed
that major emphasis should be laid on selection for
more number of pods per plant with simultaneous
improvement of biological yield per plant (g) and
harvest index (%) through their component traits for
yield improvement of seed yield in soybean.M.Sc
(Ag) ,2008
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