Cowpea (Vigna unguiculata) is an annual herbaceous legume of the genus Vigna. its ability to bind atmospheric nitrogen makes it a valuable crop for farmers with limited resources and is well suited to be combined with other crops. The whole plant is used for feed. for animals, its use as feed for cattle is probably responsible for its name.
Within the species, a high level of morphological diversity is found with large variations in the size, shape, and structure of plants. Thief peas can be erect, half-up (hanging), or curly. The crop is mainly grown for the seeds, which are rich in protein, although the leaves and unripe seed pods can also be eaten.
Cowpea was domesticated in Africa and is one of the oldest crops. The second domestication event probably took place in Asia before they spread to Europe and America.
Most cowpea is grown in the African continent, especially in Nigeria and Niger, which account for 66% of world production. In 1997, it is estimated that cowpeas are grown on 12.5 million hectares (31 million acres) of land, have a global production of 3 million tonnes, and are consumed by 200 million people daily. Insect infestation is a major impediment to cowpea production, sometimes causing crop losses of more than 90%. The legume bloodworm Maruca vitrata is the main pest of cowpea before harvest, and the loach weevil Callosobruchus maculatus is the main pest after harvest.
Taxonomy and etymology
A group of brown kidney-shaped peas, some showing a black spot.
Black eyed peas cowpeas – the common name for the cowpea variety – got their name from the presence of a characteristic black spot on its collar.
Vigna unguiculata is a member of the Vigna genus (peas and beans). Unguiculata is Latin for “with a small claw,” which reflects small stems on the petals of flowers. Common names for cultivated cowpeas include black peas, southern peas, nibé (alternatively ñebbe), and crowder peas. All cultivated cowpeas belong to the generally accepted classification of V. The classification of the wild relatives of V. unguiculata is more complex: more than 20 different names have been used and from 3 to 10 subgroups have been described. The parental subgroups stenophylla, dekindtiana and tenuis appear to be common to all taxonomic treatments, while the pubescens and protractor variations have been elevated to subspecies using the 1993 characterization.
Sea Island red peas are a variety of cowpea grown by the Gulla people in the Sea Islands.
The first written mention of the word “vigna” appeared in 1798 in the United States. The name was most likely derived from their use as a forage crop for cows. Black-eyed peas, a common name used for the unguiculata group of cultivars, describes the presence of a characteristic black spot on the seed gate. Black-eyed peas were first introduced to the southern states of the United States, and in some early varieties the peas were tightly flattened in the pods, leading to other common names for southern peas and common peas. Sesquipedalis is Latin for “foot and a half length,” and this subspecies, which arrived in the United States via Asia, is characterized by unusually long pods, giving rise to the common names for yardlin beans, asparagus beans, and Chinese long beans.
Description bush cowpea
Within the culture, there is great morphological diversity, growing conditions, and preferences of producers for each variety of the region from the region. However, since bush cowpea is mostly self-pollinating, its genetic diversity within varieties is relatively low. Thief peas can be short and bushy (up to 20 cm or 8 inches) or act like a vine, climbing over supports or dragging their feet along the ground (up to 2 m or 6 feet 7 inches). The main root can penetrate 2.4 m (7 ft 10 in) in eight weeks.
And the shape of the leaves varies greatly, making this an important trait for the classification and differentiation of varieties of cowpea. Another distinguishing feature of bush cowpea is its long stems, 20-50 cm (8-20 inches), containing flowers and seed pods. The color of the flower ranges from magenta, pink, yellow, white, and blue to various shades.
The seeds and pods of wild cowpea are very small, while the pods of various species can be 10 to 110 cm (4 to 43 inches) long. The pod may contain 6 to 13 seeds, which are usually kidney-shaped, although the seeds become more spherical the closer they are in the pod. Their texture and color are very varied. They can have a smooth or coarse coat, be mottled, stained, or stained.
Pests and diseases
The Maruca vitrata larva, commonly referred to as the maruca pod moth, is one of the most harmful insect pests to the wignum plant.
With severe infestation, insects lead to a loss of more than 90% of the crop. The bean pod waster, Maruca vitrata, is the primary pest of cowpea before harvest. Other important pests include pod sucking bugs, thrips, and the loach weevil Callosobruchus maculatus after harvest.
Other cowpea pests reported in northern Mali:
- Megalurothips sjostedti (cowpea flower thrips)
- Helicoverpa armigera (African scoop) infects cotton, cowpea, etc.
- Aphis craccivora (cowpea aphid),
- Genera Coreidae: Anoplocnemis, Clavigralla, Riptorus (foliar suckers)
M. vitrata causes the most damage to growing cowpea due to its large host range and cosmopolitan distribution. It causes damage to the buds, flowers, and pods of the plant, and infestation results in a 20–88% yield loss. Although the insect can cause damage during all stages of growth, most damage occurs during flowering. Biological control has had limited success, so most preventive methods are based on the use of agrochemicals.
The thief weevil (Callosobruchus maculatus) infects stored cowpea seeds, resulting in significant losses after harvest.
Severe infestation of C. maculatus can affect 100% of stored peas and cause losses of up to 60% within a few months. The weevil usually enters the vigen pod through the holes before harvest and lays eggs on dry seeds. The larvae burrow into the seed, feeding on the endosperm. The weevil inside the seed turns into a sexually mature adult. A single bruchid can lay 20-40 eggs, and under optimal conditions, each egg can develop into a reproductively active adult in 3 weeks. The most common methods of protection include the use of insecticides, the main pesticides used are carbamates, synthetic pyrethroids, and organophosphates.
Vorovina is susceptible to nematodes, fungal, bacterial, and viral diseases, which can lead to significant crop loss. Common diseases include blight, root rot, wilting, powdery mildew, root-knot, rust, and leaf blight. The plant is susceptible to mosaic viruses, which cause a green mosaic pattern to appear on the leaves. Vigen mosaic virus (CPMV), discovered in 1959, has become a useful research tool. CPMV is stable and easily multiplies to high yields, which makes it useful in the development of vectors and protein expression systems. Cowpea trypsin inhibitor (CpTI) is one of the means of protecting plants from attacks by some insects. CpTI has been transgenically introduced into other crops as pest control. CpTI is the only gene derived outside of B. thuringiensis that has been inserted into the commercially available genetically modified culture.
Besides biotic stresses, cowpea also faces various problems in different parts of the world, such as drought, heat and cold. Drought during the pre-flowering stage of cowpea can reduce potential yield by 360 kg/ha. Wild relatives of crops are an important source of genetic material that can be used to improve the biotic/abiotic tolerance of crops. The International Institute for Tropical Agriculture (IITA), Nigeria, and the Institut de l’Environment et de Recherches Agricoles are working on wild relatives of the cowpea to identify genetic diversity and transfer it into varieties to make them more stress-resistant and adaptive. to climate change.
Hoppin ‘John is a common rural food in the southern United States.
The cowpea is grown primarily for the production of edible beans, although the leaves, green seeds, and pods can also be eaten.
Nutrition and health
Cowpea seeds are a rich source of protein and calories, as well as minerals and vitamins. This complements the largely grain-based diet in countries where cowpea is a staple food crop. Seeds can be 25% protein and very low in fat. Cowpea starch is digested more slowly than starch from cereals, which is more beneficial for human health. Grains are a rich source of folate, an important vitamin that helps prevent neural tube defects in unborn babies.
Cowpea is often referred to as “the meat of the poor” because of the high protein levels in seeds and leaves. However, it does contain some anti-nutritional elements, including phytic acid and protease inhibitors, that reduce the nutritional value of the crop. Techniques such as fermentation, soaking, sprouting, de-branching, and autoclaving are used to combat the anti-nutritional properties of cowpea by increasing the bioavailability of nutrients in the crop. Although little research has been done on the nutritional value of leaves and immature pods, available evidence suggests that leaves have the same nutritional value as black nightshade and sweet potato leaves, while green pods have fewer anti-nutritional factors. than dried seeds.
Production and consumption
Most cowpeas are grown on the African continent, especially in Nigeria and Niger, which account for 66% of world cowpea production. The Sahel region is also home to other major producers such as Burkina Faso, Ghana, Senegal, and Mali. Niger is the main exporter of cowpea and Nigeria is the main importer. It is difficult to give exact figures for the production of cowpea as it is not the main export crop. Estimating world production of cowpea is difficult because it is usually grown in a mixture with other crops, but according to 1997 estimates, cowpea is grown on 12.5 million hectares (31 million acres) and world production is 3 million tonnes. Although they play a key role in subsistence farming and livestock feed, cowpea is also regarded as a staple commercial crop by farmers in Central and West Africa: about 200 million people consume cowpea daily.
According to the Food and Agriculture Organization of the United Nations, as of 2012, the average cowpea crop in West Africa was estimated at 483 kg per hectare (0.215 short tons/acre), still 50% below the estimated potential yield. the output of products. With some traditional cultivation methods, yields can be as low as 100 kg per hectare (0.045 short tonnes/acre).
Outside of Africa, the main production regions are Asia, Central America, and South America. Brazil is the second-largest cowpea seed producer in the world, accounting for 17% of annual cowpea production, although most of it is consumed domestically.