CROP : SOYBEAN (Glycine max)
Soybean is a member of the family Leguminoseae
, subfamily Papilionaceae. It is annual, erect bushy plant.The
flowers are borne on short axillary or terminal racemes.
The flowers are normally self-pollinated and completely
Soybean is grown, mainly in areas where
the summer is hot and humid. However, it does not withstand
extreme summer and winter. The optimum temperature for
growing soybean is 25-30 ºC. Well-drained sandy
or clay loams and alluviums with good fertility are
generally suitable for the cultivation of the crop.
Bragg, JN-2750, EC-2661
These varieties have duration of about 4 months when sown
in May-June. The duration will be less in other seasons.
The crop will perform best when sown by the onset of south-west
monsoon. Sowing after the onset of heavy showers will
result in poor germination and growth. Though it can be
grown in other seasons under irrigation, its performance
will be poor. If flowering coincides with rainy season,
fruit set will be adversely affected.
Preparation of land
As water logging will affect germination and growth
of the crop, it may be sown in raised beds during rainy
Seeds and sowing
When taking up cultivation in a new area, inoculation
with the culture of Rhizobium is desirable.
Seeds may be sown at a depth of 2-5
cm depending on season. If the soil is sufficiently
moist at the time of sowing, shallow sowing will be
better. Seeds may be sown either in lines 45 cm apart
at a distance of 10 cm between seeds in a row, or by
giving a plant-to-plant distance of 20 cm.
Apply fertilizers to provide N:P2O5:K2O
@ 20:30:10 kg/ha. The fertilizers may be applied basally.
In soils of low fertility, application of organic manures
Weed the plots once or twice depending
on weed growth. As the crop smothers the field after initial
growth, weed control will be necessary only up to 30-40
days after sowing. Earthing up at the time of weeding
The crop is free from infestation of major
pests. The minor pests include stem fly (Melanagromyza
sp.) and leaf roller (Lamrosema sp.). The stem fly mines
into stem and the plant withers and dries up. Damage is
more serious in young plants. The leaf miner causes pale
brown patches along the lamina. The flower thrip feeds
within flowers and prevents seed formation. For control
of Melanagromyza sp. apply phosphamidon 0.05%. Leaf roller
and flower thrip are controlled by dusting carbaryl 10%
The diseases include collar rot (Rhizoctonia
solani) which causes water soaked lesions at the collar
region which later spread along the whole stem. The plant
succumbs in a few days. The disease occurs in patches
under high soil moisture and high organic matter levels.
To control the disease, provide good drainage. Anthracnose
caused by Colletotrichum lindemuthianum is also common.
The fungus causes dark brown elongate, more or less angular
spots along the veins on the petioles, stem and lamina.
When infection occurs on the hypocotyl, the plant collapses.
Seeds when infected turn brown or black. To control the
disease, select seeds from disease free plots. Spraying
with ziram 0.2-0.3% is useful to check spread of the disease.
The spread of mosaic disease, characterized by mottling,
curling and distortion of leaves and malformations of
the pod is checked by rouging out the infected plant and
spraying dimethoate 0.05% to control the insect vectors.
The pod blight (Diaporthe phaseolorum) causes irregular
spots with discoloured border on the leaves and pods.
Crop rotations, destruction of diseased plants and prophylactic
foliar application of mancozeb 0.3% are recommended to
control the disease.
The crop will be ready for harvest in about
4 months after sowing. Yellowing of leaves and their shedding
are signs of maturity. If the period of maturity is rain
free, the crop may be left in the field for about a week
after complete leaf shedding. If the period is rainy,
the crop may be harvested after leaf shedding and the
produce may then be dried in shade for about 10 days.
After drying, seeds may be separated by beating with stick.
Soybean seeds lose viability after about a year. By drying
the seeds to moisture content less than 10%, reasonable
viability can be maintained up to one year. If it is not
for sowing, the seed may be stored for up to three years
The bulk of the soybean is processed industrially
into oil and protein. It may also be used as a pulse for
direct consumption after cooking. It can be substituted
for black gram and other pulses in the common household
preparations. The soybean preparations will have the characteristic
soyodour, which can be eliminated by treatment. Soybean
may also be used for making soymilk, soymilk shake, etc.
Preparation of soybean milk
Mature dry beans are washed thoroughly and soaked in
water for 8-10 hours. Remove the husk (testa) by gently
pressing the soaked seeds. Wash thoroughly and grind
to a thick paste. Alternatively, the beans may be steamed
and ground. Add water 6-8 times the volume of seeds
and bring to boil. Strain through muslin cloth. Boil
once again under gentle stirring. This milk can be kept
for 5 days in refrigerator. Periodic boiling will increase
the storage life of soymilk.
Soybean has a characteristic "bean
flavour" which is not relished by many. The acceptability
of the soymilk can be improved by removal of the "bean
flavour". For this, soak soybean in 5% starch solution
preheated to 80ºC for 8-12 hours. The starch solution
drained from cooked rice (kanjivellam) can be used for
this purpose. Soaking the beans for half an hour in
hot starch water and then allowing a continuous stream
of cold water to overflow the rim of vessels will also
give desired results.
Soybean crop yields 3-3.5 tons of grain