Description of Vigna Pygmaea R.E.Fr.
Vigna pygmaea R.E.Fr., also known as dwarf cowpea or wild cowpea, is a native of the tropical regions of East Africa. It is an annual plant and a member of the Fabaceae or pea family.
General Appearance
The plant grows up to a height of about 15-30 cm and produces small, green leaves that are usually trifoliate and oval-shaped. The flowers are small and white in color and are borne in racemes of up to about 10 flowers. The fruit of the plant is a cylindrical pod that is about 4-6 cm long and contains small, compressed seeds that are usually mottled in appearance.
Common Names
Dwarf cowpea is commonly referred to by several other names like wild cowpea, pigmy bean, and dwarf vigna. In some African countries like Kenya and Tanzania, it also goes by the local name “utekelezi”.
Uses
Vigna pygmaea R.E.Fr. is primarily used as a forage plant for livestock. The plant has high levels of protein and can be a valuable source of grazing for livestock, particularly in areas with low rainfall and poor soil quality. In some parts of the world, the young leaves, pods, and seeds are also used as a green vegetable in traditional dishes.
Light Requirements
Vigna pygmaea R.E.Fr. requires full exposure to sunlight for optimal photosynthesis. It is recommended to grow this plant in an area with at least six hours of direct sunlight daily. However, during extremely hot weather, it is ideal to provide slightly filtered light to prevent burning the leaves.
Temperature Requirements
The optimal temperature range for Vigna pygmaea R.E.Fr. is between 25°C to 35°C. It can tolerate slightly higher temperatures and low temperatures above 15°C. However, it will not survive extreme cold conditions. Therefore, it is recommended to grow this plant in regions with warm and tropical climates.
Soil Requirements
Vigna pygmaea R.E.Fr. thrives in well-draining soils rich in organic matter. It prefers sandy loam soils with a pH between 5.5 and 6.5. The ideal soil temperature range is between 25°C to 30°C, and it prefers soils that are moist but not waterlogged. The addition of organic fertilizers such as compost or farmyard manure can enhance soil fertility, which, in turn, leads to a healthy plant growth.
Cultivation Methods
Vigna pygmaea R.E.Fr. is a heat-loving plant that thrives in warm climates. It requires well-draining soil with a pH of 6-7 and plenty of sunlight. The plant can be grown from seeds or seedlings. When growing from seeds, they should be sown approximately 1-2cm deep, with a spacing of 10-15cm between each seed. For seedlings, plant them in the ground or pots at the depth of the root ball and keep the soil moist until the plant is established.
Watering Needs
Watering Vigna pygmaea R.E.Fr. can be done once or twice a week, depending on the climatic conditions and the kind of soil. It is essential to keep the soil moist but not waterlogged to avoid root rot. During the summer months or in hot climates, the plant should be watered more frequently to ensure that the soil remains adequately moist. However, overwatering should be avoided as it can lead to the plant's death.
Fertilization
Vigna pygmaea R.E.Fr. should be fertilized during the growing season to promote healthy growth and flowering. Fertilize the plant once a month using a balanced fertilizer with equal amounts of nitrogen, phosphorus, and potassium (NPK). Alternatively, organic fertilizers such as compost, bone meal, or fish emulsion can be added to the soil. However, the use of fertilizers should be moderated, and excess fertilizers should be avoided.
Pruning
Pruning Vigna pygmaea R.E.Fr. is not necessary, but it can be done to shape the plant and improve its appearance. The pruning should be done after the flowering season, and only the old and damaged branches should be pruned. It is important not to remove too many branches, as this can reduce the plant's vigour and cause a decrease in flower production.
Propagation of Vigna pygmaea R.E.Fr.
Vigna pygmaea R.E.Fr., commonly known as dwarf cowpea, is a perennial leguminous plant that is native to Kenya. It is a common food crop in East Africa and is often used in intercropping systems to improve soil fertility. Propagation of Vigna pygmaea R.E.Fr. can be done through the following methods:
Seed propagation
Seeds are the most popular method of propagating Vigna pygmaea R.E.Fr. The seeds should be planted at a depth of 1-2 cm in a well-prepared seedbed. The seeds should be spaced 10-15 cm apart with rows spaced 30-40 cm apart. The seedbed should be kept moist until the seeds germinate, which usually takes around 5-7 days.
Cuttings
Cuttings can also be used to propagate Vigna pygmaea R.E.Fr. The cuttings should be taken from healthy plants and should be around 10-15 cm in length. The cuttings should be planted in well-prepared soil and should be kept moist until they have established roots. This method is not as popular as seed propagation, but it can be useful in areas where seeds are not available.
Tissue culture
Tissue culture is a relatively new method of propagating Vigna pygmaea R.E.Fr. This method involves taking a small piece of tissue from the plant and culturing it in a laboratory. The tissue is grown in a sterile environment and is given the nutrients it needs to grow into a new plant. This method has the advantage of producing large numbers of plants in a short amount of time, but it is not commonly used due to its complexity and cost.
Disease Management
Vigna pygmaea R.E.Fr. is susceptible to various diseases that cause significant damage if not managed correctly. Some common diseases that affect the plant are as follows:
- Fusarium Wilt: It is a soil-borne disease caused by the fungus Fusarium oxysporum. The leaves of the infected plant turn yellow and wilt. The stem may also show signs of discoloration. To manage the disease, remove and destroy infected plants. Crop rotation can also help control Fusarium wilt.
- Anthracnose: It is a fungal disease that causes dark, sunken spots on leaves, stems, and pods. The pods may also have black, sunken lesions. To manage the disease, apply fungicides regularly and remove and destroy infected plant debris.
- Mosaic virus: It is a viral disease that causes yellow mottling on the leaves of affected plants. To manage the disease, remove and destroy infected plants and control insect vectors.
Pest Management
Vigna pygmaea R.E.Fr. is also susceptible to various pests that can cause significant damage. Some common pests that affect the plant are as follows:
- Aphids: They are small, soft-bodied insects that suck the sap of the plant and excrete honeydew, a sticky substance that attracts ants. To manage aphids, spray insecticidal soap or neem oil on affected plants.
- Bean leaf beetles: They are oval-shaped, yellow-green beetles with black spots that feed on the leaves of the plant. To manage the pest, apply insecticides when they appear and remove and destroy infected plant debris.
- Cutworms: They are nocturnal, caterpillar-like insects that cut off the seedlings at the soil line. To manage the pest, place collars around the base of the seedlings, remove weeds and plant debris from the garden, and apply insecticides.
