MSc

An experiment was carried out in research field of Department of Vegetable
Science, College of Horticulture, Vellanikkara during October to December 2017 to study
the performance of vegetable soybean (Glycine max L.). The main objective was to
evaluate the performance of vegetable soybean accessions for yield and quality in the
humid tropics of Kerala. Twenty eight accessions were grown in randomized block design
with three replications.
The accessions were catalogued based on the NBPGR descriptor for soybean. The
analysis of variance revealed significant differences for characters like plant height, days
to 50% flowering, days to first harvest, days to vegetable maturity, pod length, pod width,
pod yield per plant, number of pods per plant, pod weight, number of harvests, starch,
carbohydrate, protein, crude fibre, vitamin C, iron, calcium, phosphorous and polyphenol
content except number of seeds per pod and number of root nodules per plant.
The accession GM-26 was found to be the highest yielder of pods (91.80 g/plant)
with a mean of 45.43 pods per plants. The accession GM-27 had highest plant height (83.03
cm). GM-12 recorded early flowering (27 days) to flowering and early harvest (35days).
Highest pod length was observed in GM-25 and lowest pod length and width was observed
in GM-21. The quality parameters like protein and crude fibre content were recorded
highest in GM-12 and GM-14 respectively.
High genotypic coefficient of variation and phenotypic coefficient of variation were
observed for plant height, number of pods per plant, pod weight, pod yield per plant and
calcium content. High heritability coupled with genetic gain was observed for all the
morphological and quality parameters.
Pod yield per plant was significantly and positively correlated with number of pods
per plant, number of harvests, vitamin C and calcium content. Since, these associated traits
are in the desirable direction, it indicated that simultaneous selection for these traits would
be useful in improving the vegetable pod yield.
Days to 50% flowering (0.0387), days to first harvest (0.1874), pod length
(0.10380), number of pods per plant (1.1017) and pod weight (0.4408) have shown positive
direct effects on pod yield per plant while, plant height (-0.115), days to vegetable maturity
(-0.0144) and pod width (-0.2330) have shown negative direct effects on pod yield per
plant.
Twenty eight genotypes were grouped into eight clusters from estimated D2 values.
Cluster II was the largest cluster having 8 genotypes followed by Cluster V and Cluster I
with 4 genotypes, Cluster III and IV had 3 genotypes and Cluster VI, cluster VII and cluster
VIII had two genotypes each. Based on distance between clusters i.e. inter-cluster distance,
the maximum distance was observed between clusters VIII and I (D2 = 51828.79) followed
by clusters VI and I (48046.45), clusters VIII and VII (45389.69), clusters VII and VI
(38638.46) and clusters II and I (38391.70). The lowest inter cluster distance was observed
between cluster VIII and II (7406.18) followed by cluster VI and II (8460.01).
The values obtained for the vegetable soybean, GM-13 which recorded highest rank
in sensory evaluation also recorded carbohydrate (8.46 g), protein (11.43 g), crude fibre
(2.55 g), iron (5.71 mg), calcium (13.50 mg) and phosphorous (613.66 mg) content.
Present study shows that based on yield and sensory evaluation, GM-12 is the
promising genotype and it is the earliest genotype with respect to days to 50% flowering,
days to first harvest and days to vegetable maturity.