CROP : COWPEA (Vigna unguiculata)
Cowpea belongs to the family Leguminoseae.
It is a twining annual herbaceous plant. The stem is
slightly ridged and glabrous. The leaves are trifoliate
and alternate.Pods are long and cylindrical.
Cowpea can be grown throughout the year under Kerala
conditions. It can be grown as a floor crop in coconut
gardens and as an intercrop in tapioca during May-Sept.
It can be grown as a pure crop in single-crop and double-crop
rice fallows during rabi and summer seasons. Cowpea
can be grown in homestead garden throughout the year
and in kole lands of Thrissur district during summer
where rice crop cannot be raised due to water scarcity.
(1) Cowpea can be grown during any season.
(2) As a rainfed crop, sowing is done in the month of
June. The most suitable time is after the first week
(3) During the second crop season (rabi), i.e., September
to December, cowpea can be grown as a fringe crop along
the rice field bunds. Sowing can be done on either side
of bunds on the day of transplanting the paddy crop.
(4) During summer, cowpea can be grown as a pure crop
in rice fallows after the harvest of paddy.
1. Vegetable type:
(a) Bushy: Bhagyalakshmy, Pusa Barsathi, Pusa Komal. (b)
Semitrailing: Kairali, Varun, Anaswara, Kanakamony (PTB-1),
Arka Garima. (c) Trailing type: Sharika, Malika, KMV-1,
Lola, Vyjayanthi, Manjeri Local, Vyalathur Local, Kurutholapayar.
2. Grain type: C-152, S-488,
Pusa Phalguni, P-118, Pusa Do Fasli, Krishnamony (PTB-2),
V-240, Amba (V-16), GC-827, CO-3 and Pournami (in summer
3. Dual purpose type: Kanakamony
(PTB 1) and New Era
4. As companion crop with tapioca:
5. Floor crop: Gujarat V-118,
For vegetable type
Bush: 20-25 kg/ha
Trailing: 4-5 kg/ha
For grain and dual purpose type
Broadcasting: 60-65 kg/ha
(45 kg for Krishnamony)
Dibbling: 50-60 kg/ha
(40 kg for Krishnamony)
Seed inoculation and pelleting
Cowpea seeds should be inoculated with Rhizobium and
pelleted with lime. Rhizobium cultures are available
from the Assistant Soil Chemist, Microbiological Laboratory,
Soil Testing Centre, Pattambi 679 306, Palakkad District.
The strains that are available at Pattambi are the two
isolates (No.11 and No.12) developed by the Kerala Agricultural
Procedure for seed inoculation
The content of each packet of Rhizobium inoculant is
sufficient for seeds to be sown in the area indicated
on the packet (250 to 375 g/ha). Use the inoculant only
for the specific leguminous crop mentioned on the packet,
before the expiry date. Do not expose the Rhizobium
culture to direct sunlight or heat. Mix the inoculant
uniformly with the seeds by using minimum quantity of
water (instead of water, either 2.5% starch solution
or kanjivellam of the previous day can be used in order
to ensure better stickiness of the inoculant with the
treated seed material). Take care to avoid any damage
to the seed coat. Dry the inoculated seeds under shade
over a clean paper or gunny bag and sow immediately.
The Rhizobium culture or the inoculated seeds should
not be mixed with chemical fertilizers.
Procedure for lime pelleting
1. Add finely powdered (300 mesh) calcium
carbonate to moist fresh Rhizobium treated seeds and
mix for 1-3 minutes until each seed is uniformly pelleted.
Depending on the seed size, the following quantity of
lime will be required.
Small seeds 1.0 kg/10 kg of seed
Medium sized seeds 0.6 kg/10 kg of seed
Large sized seeds 0.5 kg/10 kg of seed
2. Spread out the pelleted seeds on
a clean paper to harden. Sow them as soon as possible.
However, lime pelleted seeds can be stored up to one
week in a cool place prior to sowing.
(1) Lime coating is required only for seeds that are
to be sown in acid soils.
(2) Ordinary agricultural lime is not good for pelleting
because of its larger particle size.
(3) Hydrated lime should not be used for pelleting.
(4) The dry pellet should be firm enough to resist moderate
pressure. It should appear dry without loose lime on
its surface or in the container.
(5) The lime-pelleted seeds can be mixed with the fertilizer
and sown. However, the period of contact between fertilizer
and the pelleted seeds should be as short as possible.
(6) Pelleted seeds should not be sown into a dry seedbed.]
Sowing / spacing
Plough the land thoroughly 2-3 times
and remove weeds and stubbles. Make channels of 30 cm
breadth and 15 cm depth at 2 m apart to drain off excess
rainwater. For grain type and dual-purpose type, if
dibbling is adopted, spacing of 25 cm between rows and
15 cm between plants is recommended with two seeds per
hole. If broadcasting is adopted, the seeds can be sown
broadcast over the field and channels drawn after sowing.
For bush vegetable type, spacing of 30 cm between rows
and 15 cm between plants is suitable. For semi-trailing
varieties, provide a spacing of 45 x 30 cm. Trailing
varieties can be sown in pits (@ 3 plants / pit) at
2 x 2 m spacing for trailing on pandal or in channels
at 1.5 m x 45 cm spacing for trailing on trellis.
Giving two irrigations is highly beneficial;
i.e., at 15 days after sowing and at the time of flowering.
Irrigation at the flowering stage induces better flowering
and pod set.
FYM 20 t/ha
Lime 250 kg/ha or dolomite 400 kg/ha
N 20 kg/ha
P2O5 30 kg/ha
K2O 10 kg/ha
Lime may be applied at the time of the
first ploughing. Half the quantity of N, whole of phosphorus
and potash may be applied at the time of final ploughing.
The remaining N may be applied 15-20 days after sowing.
[Note: For vegetable cowpea grown as
an intercrop in the reclaimed alluvial soils of Kuttanad,
N, P2O5, and K2O at the rate of 10, 20 and 10 kg/ha
are recommended. For vegetable cowpea, fertilizers can
be applied in several split doses at fortnightly intervals]
Hoeing at the time of application of the
second dose of N will give adequate aeration to the soil
and help the root system to spread easily. For grain and
dual-purpose varieties, decapitation is found to be advantageous
as the crop shows trailing tendency. For vegetable types,
provide trellis or pandal for trailing.
The fungus Fusarium pallidoroseum can be
used for controlling black pea aphid. Bran based fungus
can be applied at the rate of 3 kg per 400 m2 immediately
after infestation is observed. Only one application is
Spray malathion (0.05%) or quinalphos
(0.03%) for controlling pea aphids.
Spray carbaryl 0.2% or fenthion 0.05%
to protect the crop from pod borers. Repeat the application,
if infestation persists. Apply the insecticides after
harvesting mature pods and pick the pods only 10 days
after the application of insecticides.
For protecting cowpea seeds against
pests under storage conditions, smear the seeds with
groundnut or coconut oil at 1%.
The root-knot nematode and reniform
nematode associated with cowpea can be effectively managed
by the application of neem and eupatorium leaves @ 15
t/ha, two weeks before sowing.
Spray 1% Bordeaux mixture in early stages
to protect the crop from fungal diseases.
For protecting the crop from anthracnose,
treat the seeds with carbendazim (0.1%) and spray the
crop with Bordeaux mixture 1% or carbendazim 0.1%.
Green pods for use as vegetable can be
harvested 45-90 days after sowing. Pods should be harvested
while tender. For grains, the crop can be harvested in
about 90-125 days after sowing.
Cowpea for fodder purpose should be cut when it attains
the age of 40-45 days.
The threshed grains should be dried in
sun before storage.
A good crop yields about 1.2-1.5 tons of
grain and 5-6 tons of straw per hectare.
Green fodder yield is about 25-35 tons per hectare.