Overview
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. is a subspecies of the cowpea plant, which belongs to the Fabaceae family. It is primarily grown in West Africa, where it plays a significant role in local cuisine and traditional medicine.
Common Names
The plant is commonly known as Kindia cowpea, Guinea cowpea, and ugba among the Igbo people of Nigeria.
General Appearance
The plant is a creeping vine that typically grows up to 1.5 meters tall. It has trifoliate, oblong or ovate, pubescent leaves that are 6-16cm long and 3-9 cm wide. The flowers are small, yellow, and borne in axillary clusters of two to five. The seeds, which are the primary product of interest, are small and reddish-brown.
Uses
The Kindia cowpea is primarily cultivated for its seeds, which are usually boiled and eaten whole or peeled before being used in various dishes. The seeds are often used in the preparation of ugba (ukpaka), a traditional Igbo delicacy made from oilbean seeds. The plant's leaves and stems are also used in traditional medicine for treating various ailments, including dysentery, diarrhea, and fever.
Light Requirements
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. requires ample sunlight to grow. It is recommended to provide at least 6-8 hours of sunlight exposure daily to ensure healthy growth. The plant can grow under partial shade but may experience stunted growth and reduced crop yield. If growing indoors, a grow light can be used to supplement natural light.
Temperature Requirements
The plant can grow in tropical and subtropical regions with average temperatures ranging from 25°C to 35°C. However, it can tolerate a wider range of temperatures from 18°C to 38°C. It is essential to protect the plant from frost, as it is not frost tolerant. In colder regions, the plant can be grown in greenhouses to maintain the optimum temperature.
Soil Requirements
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. requires well-draining soil with ample organic matter. The ideal soil pH range is 6.0 to 7.5. The plant can grow in a variety of soil types but prefers loam or sandy loam soil. It is recommended to add compost or well-rotted manure to improve soil fertility. The plant is sensitive to waterlogging, so it is advisable to ensure adequate drainage in areas with heavy rainfall.
Cultivation Methods
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. is a warm-season crop and requires a hot and humid environment for optimal growth. The plant can be grown in a wide range of soil types, including sandy soils, loamy soils, and clay soils. However, a well-draining soil with a pH of 6.0 to 6.5 is ideal for this crop. The seeds can be sown directly in the field or in seedbeds, and the optimal temperature for germination is around 25°C.
Watering Needs
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. requires regular and uniform watering. The crop should be watered immediately after sowing the seeds, and thereafter, the crop should be watered when the topsoil becomes dry. The frequency of watering may vary depending on the climate, but the crop can be irrigated once in two to three days during the early stages of growth and once a week during the pod development stage. The crop should also be irrigated before the application of fertilizers to avoid the leaching of nutrients.
Fertilization
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. requires proper fertilization to achieve higher yields. The crop requires nitrogen, phosphorus, and potassium in adequate quantities. Farmyard manure can be added to the soil before sowing, and inorganic fertilizers can be applied in split doses during the growth stages of the crop. However, excessive use of nitrogen can lead to prolonged maturity and lower yields.
Pruning
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. generally does not require pruning, but selective pruning of diseased or damaged leaves and branches can improve the plant's health and productivity. The pruning should be done during the early stages of growth and after each harvest. The pruning should be done with sterilized tools to prevent the spread of diseases.
Propagation of Vigna unguiculata (L.) Walp. subsp. dekindtiana auct.
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. can be propagated by both sexual and asexual methods.
Sexual Propagation:
The plant produces seeds that can be used for propagation. The seeds must be cleaned and stored properly before sowing. The best time to sow the seeds is during the rainy season when the soil is moist and temperature is around 25-30°C. The seeds can be sown directly in the field or in containers. They must be covered with soil and kept moist until they germinate.
Asexual Propagation:
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. can be propagated asexually by using stem cuttings. Cuttings must be taken from healthy plants. The best time to take cuttings is during the rainy season. Cuttings of 10-15cm in length with 2-3 nodes are ideal. The lower leaves must be removed and cuttings need to be treated with rooting hormone before planting in the soil. The cuttings must be planted in a well-drained soil mix under shade. The soil must be kept moist but not waterlogged. Cuttings must be protected from excessive sunlight and temperature fluctuations until they establish roots.
Disease Management
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. can be affected by several diseases. The most common ones are:
- Anthracnose: This disease is caused by the fungus Colletotrichum spp. The symptoms include dark spots on the leaves, stems, and pods. The affected tissues may also become sunken and cracked. To manage anthracnose, it is recommended to remove and destroy infected plant debris and to apply fungicides.
- Mosaic virus: This virus is transmitted by aphids. The symptoms include yellowing and curling of leaves, stunted growth, and reduction in yield. To manage mosaic virus, it is recommended to control aphids and to remove and destroy infected plants.
- Rust: This disease is caused by the fungus Uromyces vignae. The symptoms include orange-yellow pustules on leaves and stems. To manage rust, it is recommended to remove and destroy infected plant debris and to apply fungicides.
- Southern blight: This disease is caused by the fungus Sclerotium rolfsii. The symptoms include wilting and yellowing of leaves and stems, and the appearance of white mycelium and brown sclerotia at the base of the stem. To manage southern blight, it is recommended to remove and destroy infected plant debris and to rotate crops.
Pest Management
Vigna unguiculata (L.) Walp. subsp. dekindtiana auct. can also be affected by several pests. The most common ones are:
- Aphids: These pests suck plant sap and transmit viruses. The symptoms include curled leaves and stunted growth. To manage aphids, it is recommended to remove them manually or to apply insecticides.
- Bean fly: This pest lays eggs on the soil surface near the base of the plant. The larvae feed on the roots, causing wilting and yellowing of leaves. To manage bean fly, it is recommended to apply insecticides and to rotate crops.
- Cutworms: These pests feed on the seedlings, cutting them at the base. To manage cutworms, it is recommended to apply insecticides and to protect the seedlings with collars made of paper or plastic.
- Mites: These pests suck plant sap, causing yellowing and mottling of leaves. To manage mites, it is recommended to apply insecticides and to improve plant nutrition.
