Origin
Isolona pleurocarpa Diels subsp. nigerica Keay is a plant species that belongs to the family Annonaceae. This plant is endemic to Nigeria, particularly in the Obudu Plateau region of Cross River State.
Common Names
Isolona pleurocarpa Diels subsp. nigerica Keay is commonly referred to as the African Black Plum or Obudu Plum in English, "Utele" in Igbo, and "Utien" in Efik.
Uses
The African Black Plum has significant medicinal properties. The bark, leaves, and fruit of the plant are used to treat various ailments such as malaria, dysentery, and stomach complications. The plant's extract is believed to have anticancer, antimalarial, and antifungal properties. The fruit of the plant is edible and has a sweet taste, making it suitable for making jams, jellies, and marmalades.
General Appearance
Isolona pleurocarpa Diels subsp. nigerica Keay is a small tree that grows up to 6 meters tall. The tree has a dense crown, and its leaves are glossy, oblong-shaped, and dark green. The flowers are small, yellow, and hermaphroditic. The fruit is a drupe, and it is round or oval-shaped, at maturity, it turns dark purple to black, and it contains a single seed.
Light Requirements
The plant Isolona pleurocarpa Diels subsp. nigerica Keay prefers bright indirect sunlight to thrive. It is best to keep the plant away from direct sunlight as it can scorch the leaves.
Temperature Requirements
The ideal temperature range for the Isolona pleurocarpa Diels subsp. nigerica Keay is between 18°C to 26°C. The plant is susceptible to cold temperatures, and temperatures below 12°C can be fatal.
Soil Requirements
The Isolona pleurocarpa Diels subsp. nigerica Keay prefers a well-draining, slightly acidic soil mix. The pH of the soil should be around 5.5 to 6.5. The soil should be kept moist but not waterlogged, as the plant is sensitive to root rot.
Cultivation Methods
Isolona pleurocarpa Diels subsp. nigerica Keay requires a warm and humid environment to grow. It is advisable to grow the plant in a partially shaded area, as it is susceptible to sunburn.
The soil should be well-draining and rich in nutrients. A mix of peat moss and perlite or sand is a good option. It is also ideal to plant the Isolona pleurocarpa Diels subsp. nigerica Keay in a container with drainage holes to prevent waterlogging.
The plant can be propagated by seeds or cuttings. Seeds should be planted immediately after harvesting, and cuttings should be taken during the warm and humid season.
Watering Needs
The Isolona pleurocarpa Diels subsp. nigerica Keay requires regular watering. The soil should be kept consistently moist but not waterlogged, as excess water can rot the roots.
It is essential to check the soil's moisture level periodically to prevent either under-watering or over-watering. The amount of water the plant needs depends on its location, the container's size, and the climate.
Fertilization
The Isolona pleurocarpa Diels subsp. nigerica Keay plant requires regular fertilization to promote healthy growth. A balanced fertilizer with equal nitrogen, phosphorus, and potassium (NPK) is recommended to be applied every two weeks during the growing season.
It is important to follow the manufacturer's instructions when applying the fertilizer to avoid burning the plant's roots.
Pruning
Pruning helps to maintain the plant's size and shape. It is ideal to prune at the end of the dormant season, as this will encourage new growth in the following season.
Dead or diseased branches should be removed as soon as possible to prevent the spread of the disease to the rest of the plant.
When pruning, it is advisable to use clean pruning tools to prevent the transfer of diseases.
Propagation of Isolona pleurocarpa Diels subsp. nigerica Keay
The plant Isolona pleurocarpa Diels subsp. nigerica Keay can be propagated using both sexual and asexual methods. The following are some of the propagation methods for this plant:
Seed Propagation
The plant produces viable seeds that can be planted in a well-drained potting mix. The seeds should be sown in a seed tray or pot, and they should be covered lightly with soil. It is advisable to keep the soil moist and well-drained until the seeds germinate. Once the seedlings have emerged, they should be transplanted into larger pots or directly into the garden.
Cuttings Propagation
The plant can also be propagated using cuttings. Select healthy stems without any signs of damage or disease. Cut the stem at a node, and remove all the leaves except two or three at the top. Dip the bottom end of the cutting in rooting hormone, and plant it in a well-drained potting mix. Water the cutting and cover it with a plastic bag to maintain high humidity. Place the cutting in a warm and bright location, but out of direct sunlight. Once the roots have formed, the cutting can be transplanted into a larger pot or directly into the garden.
Division Propagation
If the Isolona pleurocarpa Diels subsp. nigerica Keay has formed clumps, it can be propagated through division. Carefully dig up the clump and separate it into smaller sections, making sure that each section has enough roots. These sections can be planted directly into the garden or in pots filled with well-drained potting mix. It is essential to water the newly planted divisions well to ensure they establish quickly.
Disease Management
Isolona pleurocarpa Diels subsp. nigerica Keay is typically a hardy plant that is not prone to many diseases. However, there are a few diseases that this plant is susceptible to. Some common diseases include:
- Leaf spot: Leaf spot appears as small, brown spots on the leaves of the plant. This is caused by a fungal infection and can be treated with a fungicide.
- Root rot: Root rot occurs when the soil around the roots stays too wet for too long. The roots of the plant will start to turn brown and mushy. If caught early, the plant can be rescued by removing it from the soil, removing any affected roots, and repotting it in fresh soil.
- Powdery mildew: Powdery mildew appears as a white powder on the leaves of the plant. This is caused by a fungal infection and can be treated with a fungicide.
The best way to manage diseases is through prevention. Ensure that the plant is watered adequately, but not overwatered, and that it is planted in well-draining soil. Keeping the plant in a well-ventilated area can also help prevent fungal infections.
Pest Management
Just like with diseases, Isolona pleurocarpa Diels subsp. nigerica Keay is not highly susceptible to pests. However, there are a few common pests that can affect the plant:
- Mealybugs: Mealybugs are small, white, fluffy bugs that suck the sap of the plant. They can be treated with insecticidal soap and a fine brush to remove them from the plant.
- Spider mites: Spider mites are small, reddish-brown mites that leave a fine webbing on the plant. They can be treated with insecticidal soap or neem oil.
The best way to manage pests is through prevention and early detection. Regularly inspect the plant for any signs of pest infestation, and remove any affected leaves or branches. Keeping the plant in a well-ventilated area and avoiding over-fertilization can also help prevent pests.
