Origin
Dioscorea praehensilis Benth. is a species of yam that is native to Africa, specifically in the western part of the continent. It can be found in countries such as Nigeria, Cameroon, Ghana, and Sierra Leone.
Common Names
This plant has several common names depending on the region where it is found. In Nigeria, it is called "Isu Ewura," while in Cameroon, it is known as "Akume." The Ghanaian name for this plant is "Akokoduro," and in Sierra Leone, it is referred to as "Kponya."
Uses
The tubers of Dioscorea praehensilis Benth. are rich in carbohydrates and are a source of food for many communities in Africa. They are commonly eaten boiled, fried, or roasted, and are a staple food in some regions. The plant also has traditional medicinal uses and is believed to have anti-inflammatory properties that can help relieve pain. In addition, the leaves and stem of the plant are used in some areas for weaving baskets and making ropes due to their strength and durability.
General Appearance
Dioscorea praehensilis Benth. is a climbing plant that can grow up to 10 meters long. It has heart-shaped leaves that can reach up to 15 cm in diameter. The plant produces underground tubers that can be as large as 2 kg in weight and have a rough, brown exterior. The tubers have a white flesh that can be either dry or moist depending on the specific variety. The plant also produces small, greenish-yellow flowers that are not particularly showy.
Growth Conditions of Dioscorea praehensilis Benth.
Light: The plant requires a significant amount of sunlight to grow. It is best to grow the plant in areas where it can access full sunlight or partial shade. A minimum of 6 hours of direct sunlight is required daily for optimal growth.
Temperature: The plant does well in tropical and subtropical areas. It requires temperatures of between 20-30°C (68-86°F) for optimum growth. Temperatures below 15°C (59°F) and above 35°C (95°F) can be detrimental to the plant's growth.
Soil: Dioscorea praehensilis Benth. requires well-drained soils that are rich in organic matter. The optimal soil pH for growth is between 5.5 and 7.0. The plant can tolerate a range of soil types, including sandy, clay, or loam soils. However, the soil should be able to retain moisture well.
Water: The plant requires moderate watering, especially during the growing season. The plant should be watered generously at least once a week, especially in dry seasons. Overwatering of the plant can cause root rot, while under-watering can stunt growth.
Fertilizer: A balanced fertilizer high in potassium and nitrogen should be used to fertilize the plant. The plant should be fertilized at a frequency of once a month during the growing period.
Propagation: Dioscorea praehensilis Benth. can be propagated through seeds or vegetative means. The plant is propagated through rhizomes or stem cuttings planted about 5-10cm deep into the soil.
Overall, providing the appropriate growth conditions for Dioscorea praehensilis Benth. is crucial for successful growth and development.
Cultivation Methods
Dioscorea praehensilis Benth. is mainly propagated through tubers. It can be grown in both sandy and loamy soil types. Plant the tubers at a depth of 10-15cm and cover with soil. Ensure that the planting is done during the rainy season when the soil is moist.
Watering Needs
Watering should be done regularly to keep the soil continuously moist. However, avoid waterlogging the soil as it can cause the roots to rot. It is recommended to water the plants early in the morning or late in the evening.
Fertilization
Dioscorea praehensilis Benth. requires frequent fertilization. Apply balanced fertilizers during planting and later add nitrogenous fertilizers once a month for the first three months of growth. Afterward, phosphorous and potassium-rich fertilizers can be used to promote tuber growth.
Pruning
Pruning is not necessary for Dioscorea praehensilis Benth. However, it is crucial to manage the vines during growth to avoid entangling with other plants. This can be done by training the vines to grow along bamboo or wire trellises.
Propagation of Dioscorea praehensilis Benth.
Dioscorea praehensilis Benth. can be propagated vegetatively using tubers. However, seed propagation is also possible, but it may take a longer time and may not always guarantee the same characteristics as the parent plant. Here are the different propagation methods:
Tuber propagation
Tuber propagation is the most common method for propagating Dioscorea praehensilis Benth. It involves planting the tubers in soil or a growing medium. The tubers should be planted around 10-15 cm deep into the soil and spaced at least 60 cm apart. This is to give enough room for the vines to grow and spread out. The best time to plant the tubers is during the rainy season when the soil is moist and there is enough water for the plant to grow.
After planting the tubers, it is important to provide support for the vines to grow. This can be done using stakes, trellises or other support structures, as the vines can grow up to 10 meters long. The vines will start to grow after a few weeks, and it is important to keep the soil moist throughout the growing season.
Seed propagation
Seed propagation of Dioscorea praehensilis Benth. involves collecting the mature seeds from the parent plant and planting them in a growing medium. The seeds should be planted around 2-3 cm deep into the soil and spaced at least 30 cm apart. The best time to plant the seeds is during the rainy season.
The seeds will germinate after a few weeks, and it is important to keep the soil moist throughout the growing season. As the seedlings grow, it is important to thin them out and space them adequately to prevent overcrowding. The seedlings should also be protected from pests and diseases.
Overall, Dioscorea praehensilis Benth. can be propagated using tubers or seeds. Tuber propagation is the most common method and involves planting the tubers in soil or a growing medium, while seed propagation involves planting mature seeds in a growing medium.
Disease and Pest Management for Dioscorea praehensilis Benth.
Dioscorea praehensilis Benth., commonly known as the water yam, is a tropical plant that is often used for its edible tubers. Like many plants, it is susceptible to a range of pests and diseases, which can impact yields and quality. Effective disease and pest management practices are essential if you want to keep your water yam plants healthy and productive.
Common Diseases
The water yam can be affected by a range of diseases, including:
- Anthracnose: Anthracnose is a fungal disease that causes lesions on the leaves, stems, and fruits of the plant. It can impact plant growth and yield.
- Bacterial wilt: Bacterial wilt is a disease that causes wilting, yellowing, and eventual death of the plant. It is caused by the bacterium Erwinia chrysanthemi.
- Leaf spot: Leaf spot is a fungal disease that causes circular spots on the leaves. It can cause defoliation and impact plant growth.
- Root rot: Root rot is a fungal disease that causes the roots of the plant to rot. It can stunt plant growth and reduce yields.
Pest Management
Water yam plants can also be affected by a range of pests, including:
- Spider mites: Spider mites are tiny pests that suck the sap from the leaves of the plant. They can cause yellowing and curling of the leaves, as well as stunting of plant growth.
- Caterpillars: Caterpillars can be a problem for young water yam plants, as they can eat the leaves and bore into the stem of the plant.
- Whiteflies: Whiteflies are small, sap-sucking insects that can cause yellowing and wilting of the leaves, as well as the spread of viral diseases.
Disease Management
Preventative measures are the best way to manage water yam diseases. Here are some ways to avoid common diseases:
- Clean planting material: Use clean planting material that is free from disease.
- Proper irrigation: Overwatering can lead to fungal diseases, so it's important to provide proper irrigation. Water yams should be watered deeply but infrequently.
- Fungicides: Fungicides can be used to prevent and manage fungal diseases. They should be applied according to the label instructions.
- Cultural practices: Cultural practices, such as crop rotation and proper spacing, can help to prevent diseases from taking hold in your water yam plants.
Pest Management
Here are some ways to prevent or manage pests affecting water yam plants:
- Clean planting material: Use clean planting material that is free from pests.
- Beneficial insects: Encourage beneficial insects, such as ladybugs and lacewings, which can help to control pest populations naturally.
- Pesticides: Pesticides can be used to manage pests, but they should be used judiciously and only when necessary. Always follow label instructions and take precautions to protect beneficial insects.
- Cultural practices: Cultural practices, such as removing weeds and debris, can help to reduce pest populations.
By implementing effective disease and pest management practices, you can help to keep your water yam plants healthy and productive, ensuring a bountiful harvest for years to come.
