INTRODUCTION
HISTORY
1. It is very rich in protein contents because its leaves contain more proteins than its beans. Similarly it has the highest contents of proteins among rest of the legumes.
2. Other point of its success lies in its drought tolerance and tolerance to high temperature and hence it can easily be grown where other legumes cannot be grown. So it is being cultivated in cotton growing regions of Punjab, Pakistan.
The cowpea (Vigna unguiculata (L.) Walp.) has diploid chromosome number (2n = 22) and haploid chromosomes number (n = 11). Cowpea is a warm season, annual, herbaceous crop and grown as Kharif legume in Pakistan. It is a self-pollinated crop. It has different plant types like erect, semi-erect, prostrate (trailing) and climbing. The growth may be determinate or indeterminate.
1. ROOT AND SHOOT: The plant is strongly taprooted and the length of the taproot has been measured to be 95 inches 8 week after seeding. It ranges in size from small wild types to 14 inches longs stems of some cultivars.
2. LEAVES: The leaves are trifoliate and develop alternately, they are smooth and dull to shiny in appearance. There is a wide range of leafy shapes and sizes.
3. FLOWERS: Cowpea is a short-day to day-neutral plant and usually self-pollinated. The flower is white or purple. Peduncles (flower stalks) arise from the leaf axil, and 2-3 pods per peduncle are common and there may b 4-8 pods also. The long size of peduncle makes it easy to harvest the pods from the plant.
4. PODS: The cowpea pod is usually 4-10 inches long in different subspecies and cultivars. It is smooth, cylindrical and somewhat curved. As the seed matures in the pod, the pod colour also changes and it can be green, yellow or purple. And when the seeds dry the pod colour changes to tan or brown.
5. SEEDS: The seeds are kidney shaped either smooth or pigmented. White seeds are preferred by the farmers. The pigment may form a black mark around the hilum, which is called black eye. Hence the crop is also know as Black-eyed pea.
GROWTH REQUIREMENTS
1. SEASON OF GROWTH: It is a short day, summer crop.
2. ENVIRONMENTAL RESISTANCE AND TOLERANCE: It is resistant to drought and high temperature but can not tolerate frost.
3. IRRIGATION AND RAINFALL: It also give good results both with the irrigated and rainfed areas. In case of irrigated lands, there is more vegetative growth and delay in the pod formation. But it performs equally well in the dry, rainfed areas hence making it a very popular crop among the underdeveloped countries where there is shortage of water.
4. SOIL REQUIREMENTS: Cowpea can be grown on a wide variety of soils. Sandy-loams are considered best although it can be grown on hard clay soils where its vegetative growth is rich but it comes at the cost of reduction in the bean production. It is also a little tolerant to salinity and performs well in the pH range of 5.5 - 6.5. It performs well in well drained and well prepared seedbeds.
It performs good altitudes (0-1500m) but can also be sown at higher altitudes.
5. RHIZOBIUM RELATIONSHIP: It is good nitrogen fixing ability due to root nodules formation and when it is inoculated with Rhizobium it gives better yields.
6. COMPATIBILITY WITH CEREALS AND OTHER LEGUMES: It can be grown together with millet, sorghum or maize, where it does not compete with perennial crops due to its annual nature.
PESTS AND DISEASES
DISEASES: Many stem and root rots are reported. Other diseases include Fusarium wilt, Septoria leafspots and mildews. A few viruses also attack the plant producing symptoms on the leaves, stem and causing little or no yield because either pods are not formed or malformed.
PESTS: Pod borers, stem borers, leaf hoppers, aphids are common insects. Witchweed and nematodes have also been reported in Zimbabwe.
MAIN ATTRIBUTES AND DEFICIENCIES
ATTRIBUTES:
Cowpea ( لوبیا )is one of the most important legumes being cultivated in the semi-arid and sub-humid tropics for its grain and fodder purposes. Among all the legumes, cowpea has much tolerance to drought, it is a warm weather crop and hence well adapted to dry regions. So, its world production and acreage has increased dramatically in the last 25 years. In Pakistan, it is grown mainly as Kharif crop, with sorghum and millet intercropping.
Black-eyed Pea |
NOMENCLATURE
Vernacular Names: Cowpea, Southern pea (USA), Blacke-eyed pea (Common), Crowder pea (USA), Lobia (Pakistan, India), Rawan (Pakistan), other local names in different world countries include fiebe, coupe and so on.
Technical Name: Vigna unguiculata (L.) Walp. (It also has many synonyms but this name is more commonly used.)
BIOLOGICAL CLASSIFICATION
1. Vigna ungiculata subsp. cylindrica known as Catjang
2. Vigna ungiculata subsp. dekindtiana
3. Vigna ungiculata subsp. unguiculata known as Black-eyed pea
4. Vigna ungiculata subsp. sesquipedalis known as Yardlong pea (longer pod size)
HISTORY
Cowpea has its origin in Africa. Its history dates back 5-6 thousand years in West Africa where it was grown as legume crop with pearl millet and sorghum. It was also known to ancient Greeks and Romans. From Afica, it was probably take by slave trade to the North America.
IMPORTANCE
Fresh Green Leaves Used as Food |
2. Other point of its success lies in its drought tolerance and tolerance to high temperature and hence it can easily be grown where other legumes cannot be grown. So it is being cultivated in cotton growing regions of Punjab, Pakistan.
3. Cowpea is a multipurpose crop, because it can be grown for its mature beans, which serve as pulses, or it is grown for its immature pods and leaves which are used as vegetable. The stem or haulm serves as fodder for livestock.
4. Recently, it has been adopted as pulse crop by most of the African countries and in other agriculturally developed nations it is being cultivated as forage and/or cover crop.
It can be used for green manuring of the field due to its nitrogen fixing root nodules.
It can be used for green manuring of the field due to its nitrogen fixing root nodules.
Table: Percentages for different nutrients in Cowpea beans (average for 8 cultivars)
Proteins
|
24.8%
|
Fats
|
1.9%
|
Carbohydrates
|
63.6%
|
Fibre
|
6.3%
|
ECONOMIC IMPORTANCE
It is being used as pulse crop, forage crop and vegetable crop. The world annual production is more than 2.0 million ton from a cultivated area of about 6.0 million hectares. Nigeria is the leading world producer of the cowpea grain followed by Brazil. In Pakistan, it is being produced and consumed by the subsistence farmers, particularly in the barani zones. It is usually intercropped with sorghum and millet.
It is used to make dishes of different kinds according to the tradition of the local region. Its nutritional value is enhanced when cooked with cereal crops. In Pakistan, it is being cooked in to variety of dishes and served with rice also.
PLANT CHARACTERISTICS
Vigna unguiculata plant |
1. ROOT AND SHOOT: The plant is strongly taprooted and the length of the taproot has been measured to be 95 inches 8 week after seeding. It ranges in size from small wild types to 14 inches longs stems of some cultivars.
2. LEAVES: The leaves are trifoliate and develop alternately, they are smooth and dull to shiny in appearance. There is a wide range of leafy shapes and sizes.
Vigna unguiculata Flower |
4. PODS: The cowpea pod is usually 4-10 inches long in different subspecies and cultivars. It is smooth, cylindrical and somewhat curved. As the seed matures in the pod, the pod colour also changes and it can be green, yellow or purple. And when the seeds dry the pod colour changes to tan or brown.
5. SEEDS: The seeds are kidney shaped either smooth or pigmented. White seeds are preferred by the farmers. The pigment may form a black mark around the hilum, which is called black eye. Hence the crop is also know as Black-eyed pea.
GROWTH REQUIREMENTS
1. SEASON OF GROWTH: It is a short day, summer crop.
2. ENVIRONMENTAL RESISTANCE AND TOLERANCE: It is resistant to drought and high temperature but can not tolerate frost.
3. IRRIGATION AND RAINFALL: It also give good results both with the irrigated and rainfed areas. In case of irrigated lands, there is more vegetative growth and delay in the pod formation. But it performs equally well in the dry, rainfed areas hence making it a very popular crop among the underdeveloped countries where there is shortage of water.
4. SOIL REQUIREMENTS: Cowpea can be grown on a wide variety of soils. Sandy-loams are considered best although it can be grown on hard clay soils where its vegetative growth is rich but it comes at the cost of reduction in the bean production. It is also a little tolerant to salinity and performs well in the pH range of 5.5 - 6.5. It performs well in well drained and well prepared seedbeds.
It performs good altitudes (0-1500m) but can also be sown at higher altitudes.
5. RHIZOBIUM RELATIONSHIP: It is good nitrogen fixing ability due to root nodules formation and when it is inoculated with Rhizobium it gives better yields.
6. COMPATIBILITY WITH CEREALS AND OTHER LEGUMES: It can be grown together with millet, sorghum or maize, where it does not compete with perennial crops due to its annual nature.
PESTS AND DISEASES
DISEASES: Many stem and root rots are reported. Other diseases include Fusarium wilt, Septoria leafspots and mildews. A few viruses also attack the plant producing symptoms on the leaves, stem and causing little or no yield because either pods are not formed or malformed.
PESTS: Pod borers, stem borers, leaf hoppers, aphids are common insects. Witchweed and nematodes have also been reported in Zimbabwe.
MAIN ATTRIBUTES AND DEFICIENCIES
ATTRIBUTES:
- High protein contents than all other legumes.
- A very good catch crop to reclaim fertility of the soil.
- Good performance under dry conditions and hot temperature.
- Highly vigorous seedlings and can grow very fast.
- It has a rich grazing capability for the dairy animals as well as other livestock.
- Competes fairly well with the small weeds but not with tall weeds.
- It is an annual susceptible to frost.
- Thick stem making it difficult for haymaking.
- Flooding is damaging to the crop.