Cowpea is a typical warm season crop adapted to tropics. The crop is used in a variety of ways. Tender pods are used as a vegetable and dry beans as a pulse. Due to its nutritive value and soil improving properties, it is also used as fodder, green manure, and cover crop. Being a legume crop, cowpea fits well in the intercropping system. In Kerala, it is grown as a floor crop in coconut gardens, as an inter-crop in tapioca, fringe crop in rice fields and garden lands. The crop is an integral part of sustainable agriculture. 100 g of green tender pods contain 4.3 g protein, 2.0 fibre, 8.0 g carbohydrates, 74 mg phosphorus, 2.5 mg iron, 13.0 mg vitamin-C,0.9 mg minerals, etc. (Africa is considered as primary center of origin of cowpea)
Scientific Name-Vigna unguiculata
Land preparation for growing Cowpea
Prepare the land by ploughing at right moisture situation and level the surface by planking to conserve the moisture using a country plough or stir the soil using a rotavator. Take care to uproot the weeds fully and allow them to dry out.
Sowing time for Cowpea
Ensure an optimal plant population for better yield potential. Use only local Cowpea selection having higher yield potential which is more economical. About 35-40 kg seed is required to plant one ha. Treat this seed with 375-500 g of Rhizobium before sowing specially in newly cultivated areas so as to ensure the benefit of biological nitrogen fixation. Open the planting lines at a required spacing (45cm for Alsondo-1 Selection and 60 cm for Goa Nadora and Goa Cowpea-3). It is better to sow in plough-sole so as to place the seed in the moist zone at a depth of 5 cm.
Varieties of cowpea
One of the main reasons for the low productivity of cowpea is a lack of a suitable high-yielding variety of the crop. Sporadic attempts to introduce few high yielding types of small seeded cowpea were although made, yet these varieties could not become popular among the farmers owing to local preferences for bold grain types. This is because Local Cowpea (Alsondo) is a delicacy in the region owing to its unique taste and bold sized seeds. ICAR Research Complex for Goa with its research efforts in the collection, cataloging, evaluation and selection for specific traits over a period of last one decade, has identified three selections of local cowpea with specific advantages.
It is a determinate type of local cowpea selection with bold pods and high yield. It grows to a height of 55 cm with 3-4 primary branches under normal conditions. It responds well to a spacing of 45 cm to accommodate more plants per unit area. Under ideal conditions, the selection produces 12-13 long pods having a length of 24-25cm with 15-16 seeds per pod. The test weight of the selection is around 20-21g/100 seeds. The harvest index of the selection is quite high (0.54). The selection has a potential seed yield of 1290 kg/ha and a haulm yield up to 3t/ha. The selection takes about 47 days to flower and matures in 90 days.
2.Goa Nadora (Nadora Bardez-4)
It is an indeterminate type of local cowpea selection with bold pods and high yield. It grows profuse with dense foliage (up to 44 trifoliate leaves/plant) with 2-3 primary branches under ideal conditions. The selection takes 63-65 days for flowering with a total crop duration of 100 days. The selection produces pods in clusters with 6 to 10 pods/plant having a length of 18 to 22cm. Normally each pod will have 10 to 14 seeds with a test weight of 24 g for 100 seeds. The selection has a potential seed yield of 1630 kg/ha and a haulm yield of 3.31 t/ha.
3.Dhulape Utorda-3 (Goa Cowpea-3)
It is also an indeterminate type of local cowpea selection with bold pods and high yield. It grows to the height of about feet with profuse dense foliage (up to 40 trifoliate leaves/plant) with vine growth up to one meter having 4-5 primary branches under ideal conditions. The selection takes 68-70 days for flowering with total crop duration of 100-105 days. Each plant produces 14-20 smooth greenish white pods in clusters measuring 23- 25cm. Each pod will have 13 to 17 light brownish seeds having a test weight of 25 g for 100 seeds. The selection has a potential seed yield up to 2000 kg/ha and a haulm yield of 4.30 t/ha.
The crop is grown extensively as a rice fallow crop under residual moisture situations in the region. However, late sown crop gives better response for 1-2 irrigations. Excess moisture availability, especially in the early stages of the crop, will not only produce more vegetative growth but also reduces yield and delays the crop.
Use of Rotary hoe in the line planted crop helps in minimization of weeds. Early weed control for first 45 days is crucial to ensure higher yield.
Harvesting of Cowpea
The crop will be ready for harvest in about 100–105 days under residual moisture situation. Pluck the pods on maturity once they turn brown, dry the pods immediately and thresh the produce. Dry the seeds to reduce the moisture level below 10–12 % and add finely grounded Tirphal / boric acid powder @ 2 g / kg of seeds to reduce the infestation by stored grain pests.
Properly dried local cowpea is relatively more tolerant to the infestation of pulse beetle than small seeded cowpea varieties like C-152. Use of insecticide carbaryl @2.5 g/kg is more effective in inhibiting the pulse beetle attack without affecting the germination of the seeds.
“ICAR Research Complex for Goa – ccari.res.in.” Central Coastal agriculture research institute. N.p., n.d. Web. 05 May. 2017 <http://www.ccari.res.in/dss/cowpea.html>.
ICAR Research Complex for Goa – ccari.res.in. (n.d.). Retrieved from http://www.ccari.res.in/dss/cowpea.html
- ICAR-CENTRAL COASTAL AGRICULTURAL RESEARCH INSTITUTE