Cowpea

Cowpea (Vigna unguiculata (L.) Walp.) is of vital importance to the livelihoods of millions of people in the semi-arid regions of West and Central Africa. It is the most important grain legume crop in sub-Saharan Africa. Cowpea is mostly grown by smallholders in the hot, drought-prone savannas and very arid Sahelian agro-ecological zones, often intercropped with pearl millet and sorghum. Cowpea is a protein-rich grain that complements staple cereal and starchy tuber crops. It also provides fodder for livestock, improves the soil by fixing nitrogen, and benefits households by bringing in cash and diversifying sources of income. The sale of cowpea stems and leaves for animal feed during the dry season provides vital household income.

Field workers harvesting cowpea (Photo: IITA)
Field workers harvesting cowpea (Photo: IITA)

Origin and use

Cowpea originated and was domesticated in Southern Africa and later spread to East and West Africa and Asia.

The crop can be harvested at three stages: when the pods are young and green, when the pods are mature and green, and when the pods are dry. The young leaves, immature pods, immature seeds, and the mature dried seeds are all used as food. The stems, leaves, and vines serve as animal feed and are often stored for use during the dry season. In Nigeria, farmers who cut and store cowpea fodder for sale at the peak of the dry season increase their annual income by 25%. Women prepare and sell snacks made from cowpea, and are also mainly involved in the sale of green pods.

Fifty-two percent of Africa’s production is used for food, 13% as animal feed, 10% for seed, 9% for other uses, and 16% is wasted.

Production

An estimated 14.5 million hectares of land is planted to cowpea each year worldwide. Global production of dried cowpeas in 2010 was 5.5 million metric tons; Africa was responsible for 94% of this. Nigeria is the largest producer and consumer of cowpea, producing 2.2 million metric tons of dried grain in 2010. Niger is the second largest producer, followed by Burkina Faso, Myanmar, Cameroon, and Mali. The average yield worldwide is estimated at 450 kilograms per hectare, the lowest of the major tropical grain legumes. An estimated 38 million households (194 million people) grow cowpea in sub-Saharan Africa, but productivity has not seen sustained growth over the last two decades – total area, yield, and production grew by 4.3%, 1.5%, and 5.8%, respectively.

Nutrition

The grain contains 25% protein, and several vitamins and minerals.

Impact of CGIAR Centers

The net present value of benefits from investment in cowpea research and extension by the International Institute of Tropical Agriculture (IITA) over 20 years is estimated at upwards of US$1.09 billion with an internal rate of return of between 50 and 103%.

In the semi-arid region of West and Central Africa, farmers traditionally cultivate different cowpea varieties for grain and fodder. In the early 1990s, IITA, in collaboration with the International Livestock Research Institute (ILRI), developed improved cowpea varieties that produce both grain for human consumption and fodder for livestock during the dry season. The diffusion and uptake of one of these varieties in Kano State, Nigeria, was very impressive. By 1997, only four years after its accidental release to one farmer, it had reached over 1,500 farmers. Farmers found that adopting this dry-season, dual-purpose cowpea brought many benefits. These include food security during a critical period of the year, cash income, crop diversification, fodder, and in situ grazing after harvesting, in periods when the prices of cowpea grain peak, and when good quality fodder is scarce. These dual-purpose cowpea varieties are now being widely adopted in the dry savannas of West Africa, with estimated benefits of between US$299 million and US$1.1 billion expected to accrue from 2000 to 2020.

Cowpea production and processing is propelling a silent revolution in Nigeria, as incomes from the crop improve rural livelihoods. Processing cowpea is almost exclusively undertaken by women. They produce a range of products that are sold as street food, including moin-moin (ground cowpea mixed with other ingredients and boiled or steamed to make a meat substitute), and akara, a deep-fat fried fritter – the most popular of the cowpea-based food products.

“The benefits are many,” says Mrs. Olaiya Oluwakemi, an akara vendor in Osu, a community in southwestern Nigeria, “From frying of akara alone, I have been able to afford to send my son to university. I built a house and now own a car.” Her business has grown in the last seven years and she currently employs more than 20 people. On average, she makes a profit of US$10–13 a day.

Elsewhere in northern Nigeria, home to cowpea production, the crop is improving the livelihoods of farmers. Cowpea farmers using improved cowpea varieties and management practices have seen their incomes increase by on average 55%. Besides improving incomes, interventions by IITA and its partners are helping farmers with improved technologies to meet the increasing demand for the crop.

Sources and more information