COWPEAA grain legume crop

Weed control, disease and pestsGood seedbed preparation and weed control prior to planting is critical for good crop establishment. Cowpea is susceptible to a wide range of diseases and pests, including post-harvest insects attacking grain. Insect pests, in particular Aphids, need to be sprayed regularly. There are several insecticides available, (e.g. Metasystox, Karate and Talstar) and these should be applied following the guidelines on the label – protective clothing must be worn. Smallholder farmers have reported that repeatedly spraying the plant with a solution of crushed chilli is effective at controlling Aphids.

Harvested seed is best protected from insect pests by storage in airtight containers or bags. If seed is to be kept for planting, a fumigant treatment such as Phostoxin should be carefully applied – farmers will require proper training for its safe use.

Yield and seed qualityYield is determined by a range of environmental factors and agronomic management. In commercial dryland situations seed yield is commonly reported as greater than 1.5 t/ha. Field trial and modelling results have shown that cowpea yield under the smallholder farming systems in the Limpopo province is reliable, and will produce harvestable crop yields in approximately 90 percent of the growing seasons where good agronomy is practiced. In smallholder systems where cowpea is grown on poor or shallow soils, seed yield ranges from 0.4 to 0.6 t/ha, whereas on deeper sandy loam soils its yield ranges from 0.6 to 1 t/ha. Under good management the potential yield of the two new ARC varieties is >2 t/ha.

COWPEA

Useful websiteshttp://www.tropicalforages.info/

http://www.arc.agric.za

IntroductionCowpea (Vigna unguiculata)

(also known as Dinawa or Tinyawa) is an indigenous tropical legume that produces pods and grain that are highly nutritious and valuable.

It is well adapted to cultivation in dryland and irrigated farming systems in Limpopo province, being tolerant

to drought and poor soil conditions, but is

currently underutilised by smallholder and commercial

farmers.

Compiled byAnthony Whitbread (CSIRO), Kingsley Ayisi (Jodems Agri-Pioneers)

and Joseph Asiwe (ARC)

COWPEA

Contact numbersMr Jeffery Mkhari, Limpopo Department of Agriculture, Agronomy and Research Innovation Division. Phone: 015 294 3000Dr Kingsley Ayisi, Jodems Agri-Pioneers. Phone: 083 648 2599Dr Joseph Asiwe, Plant Breeder – Cowpeas, ARC Potchefstroom. Phone: 018 299 6100/6340

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Uses of the Cowpea plantCowpea, a legume that biologically fi xes nitrogen from the atmosphere, can be used as a vegetable crop (leaves and pods), grain crop (seeds), a source of fodder and a break crop grown in rotation with cereals. Good quality cowpea seed is readily purchased by local milling companies. Informal trading of cowpea products by smallholder farmers can be lucrative, particularly if seed is properly stored and sold late in the dry season.

Climate and soil requirementsCowpea grows best in areas that receive summer rainfall. Rapid germination requires soil temperatures above 200C. Growth, fl owering and pod formation is also best under warm temperatures (25-300C). Cowpea is adapted to a wide range of soils but with a preference for well drained sandy loams that

allow good rooting. It is tolerant of a wide range of soil pH and better adapted to strongly

acid (pH 4) low-fertility soils than most legumes.

Sowing time and growing periodUnder rainfed conditions, sowing time is dependent on rainfall- the time of sowing should ensure that pod development and seed fi lling is not reduced by falling temperatures or destroyed by frost. High temperatures during fl owering can result in fl owers being aborted. In Limpopo province, sowing time can take place from late November through to

late January. Depending on the variety, fl owering will begin in 45-80 days, pod development around 55-80 days continuing through to maturity in 90-120 days after planting.

Farming system and agronomy Commercially, cowpea is mostly grown as a sole culture. Under some low input smallholder systems, it is often intercropped with Maize. Under dryland conditions in Limpopo province, spacings between rows should be about 50 cm, with spacing between plants of about 30 cm. Seed should be planted at a depth of 3-5 cm. For planting with machinery, rates of 10-15kg/ha are recommended.

As with all legume crops, phosphorus (P) is an essential nutrient and should be applied where soil P is low. If the soil is acidic, applying lime can help make soil P more available. The application of Bradyrhizobium strain CB756 (XS21) to seed at planting may also help improve growth, although cowpea is likely to nodulate with native soil rhizobia.

VarietyWorldwide, there are hundreds of varieties of cowpea ranging from grain types (erect or bunch), through to less determinate dual purpose grain/fodder types (trailing or spreading). Many varieties are well adapted to Limpopo province with the following selections tested. There are also several well adapted local types planted by farmers in rural communities.

Commercially, cowpea is mostly grown as a sole culture.

Worldwide, there are hundreds of varieties of cowpea ranging from grain types (erect or bunch), through to less determinate

allow good rooting. It is tolerant of a wide range of soil pH and better adapted to strongly

acid (pH 4) low-fertility soils than most legumes.

Sowing time and growing periodUnder rainfed conditions, sowing time is dependent on rainfall- the time of sowing should ensure that pod development and seed fi lling is not reduced

can result in fl owers being aborted. In Limpopo province, sowing time can take place from late November through to

fi xes nitrogen from the atmosphere, can be used as a vegetable crop (leaves and pods),

COWPEA

Seed colour Habit Flowering(DAP)

Maturity(DAP)

Main use

Blackeye Cream/black eye Erect 60 90 Grain

Pan311 Cream Erect 60 90 Grain

Pan326 Dark grey Erect 65 95 Grain

Bechuana White White Trailing 45-60 70-90 Leaf/grain

Agrinawa Maroon Trailing 45-65 80-100 Leaf/grain

Glenda Brown Trailing 45-60 70-90 Leaf/grain

ARC-GCI-Cp-27 White Semi-erect 45 90 Grain

ARC-GCI-Cp-76 Brown Semi-erect 45 90 Grain

The leaves of Cowpeas are commonly dried and consumed during the dry season

The Blackeye variety of Cowpea is popular as a grain crop

Intercropping maize and a trailing variety of

Cowpea to improve soil fertility

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