Overview:
Strychnos unguacha A.Rich. var. dschurica Gilg, also known as the "Tanzanian arrow poison plant," is a poisonous plant species that belongs to the plant family Loganiaceae. This plant is indigenous to the tropical and subtropical regions of Africa and is widely used by local indigenous people for medicinal and poisonous purposes.
Origin:
The Tanzanian arrow poison plant is native to tropical and subtropical regions of Africa. It grows naturally in Tanzania, Kenya, and Uganda, specifically in the forested regions and areas near rivers.
Common Names:
Strychnos unguacha A.Rich. var. dschurica Gilg is known by various common names depending on its location. Some of these names include Tangunzuin, Mululu, Mweru, and Muzungu in Tanzania; Munzizi in Kenya; and Engada, Kiyaruzi, Kimwara, and Kinyalu in Uganda.
Uses:
The Tanzanian arrow poison plant is widely used by local indigenous people for medicinal and poisonous purposes. The plant's bark, roots, and leaves have potent therapeutic properties that have been utilized to treat various ailments such as fever, malaria, and stomach upset. The plant's seeds, on the other hand, are highly poisonous and are commonly used to make arrow poison by many indigenous cultures.
General Appearance:
The Tanzanian arrow poison plant is a small to medium-sized tree that can grow up to 20 meters in height. Its leaves are bright green and glossy, with a leathery texture and an elliptical shape. The plant's bark is smooth and greyish-brown, and its fruits are small, round, and green, turning yellow when ripe. The plant's flowers are small and white, with a tube-like shape, and blooming in clusters.
Light Requirements:
Strychnos unguacha A.Rich. var. dschurica Gilg requires a moderate to high level of sunlight to grow properly. It is suited to grow in areas with partial or full exposure to sunlight. Extreme conditions such as direct sunlight or complete shade may have adverse effects on its growth.
Temperature Requirements:
The plant grows best in warm to hot climates with temperatures ranging from 24°C to 33°C. It can still survive in lower temperatures down to 10°C, but growth may be stunted or halted altogether. Temperatures exceeding the threshold of 33°C may cause damage to the plant.
Soil Requirements:
The Strychnos unguacha A.Rich. var. dschurica Gilg prefers well-draining soil with a pH ranging from 5.5 to 7.5. It can tolerate a wide range of soil types, including sandy, loamy, and rocky soils. However, the soil must contain sufficient nutrients, specifically nitrogen, potassium, and phosphorus. Generally, a nutrient-rich soil with good drainage is most ideal for its growth.
Cultivation Methods
Strychnos unguacha A.Rich. var. dschurica Gilg is a tropical plant that prefers hot and humid conditions. It grows best in well-drained soil with a pH level ranging from 6 to 7.5. The seeds are usually sown in seedbeds and kept in a warm place for germination. Once they have grown, the seedlings can be transplanted into pots or the ground, preferably in an area with partial shade. The plant can also be propagated by stem cuttings or layering.
Watering Needs
Strychnos unguacha A.Rich. var. dschurica Gilg requires regular watering, especially during periods of dry weather. However, it is essential not to overwater the plant, as this can cause root rot. Water the plant thoroughly and ensure that the soil is moist but not waterlogged. Mulching around the base of the plant can help to retain moisture and prevent weed growth.
Fertilization
Fertilization with a balanced fertilizer can help to enhance the growth of Strychnos unguacha A.Rich. var. dschurica Gilg. Apply fertilizer during the growing season, and make sure to follow the recommended dosage on the package. Too much fertilizer can cause damage to the plant, so it is necessary to exercise caution.
Pruning
Strychnos unguacha A.Rich. var. dschurica Gilg benefits from regular pruning, which helps to maintain its shape and prevent overcrowding. The best time to prune this plant is during the dormant season when it is not actively growing. Remove any dead, diseased, or damaged branches, as well as those that are crossing or rubbing against each other. You can also trim the tips of the branches to encourage bushier growth.
Propagation of Strychnos unguacha A.Rich. var. dschurica Gilg
Strychnos unguacha A.Rich. var. dschurica Gilg can be propagated through various methods such as seed propagation, vegetative propagation, and tissue culture.
Seed Propagation
Seed propagation is the most common method used to propagate Strychnos unguacha A.Rich. var. dschurica Gilg. The seeds must be collected from mature fruits and are then treated with hot water (about 50-60°C) for 1-2 minutes to break their dormancy. The seeds can then be sowed in seedbeds, and they usually take about 2-3 weeks to germinate. The seedlings can then be transplanted to containers or directly to the field.
Vegetative Propagation
Vegetative propagation is another feasible method of propagating Strychnos unguacha A.Rich. var. dschurica Gilg. This can be done through cuttings or grafting. Cuttings are taken from the tree's branches and rooted in the right medium. The plants' branches must be pruned at the end of the wet season to facilitate rooting and establishment during the dry season. However, the success rate of vegetatively propagated plants is low. Therefore, grafting onto rootstock should be considered.
Tissue Culture
Tissue culture is an alternative method of propagating Strychnos unguacha A.Rich. var. dschurica Gilg. This method is not commonly used due to its high cost. However, it has several advantages over traditional methods such as the production of disease-free plants and the production of a large number of plants in a short period. It involves the use of plant tissues or cells on a nutrient medium under controlled conditions to regenerate into plantlets. The resulting plantlets can be hardened in the greenhouse before transplanting into the field.
Disease Management
Strychnos unguacha A.Rich. var. dschurica Gilg may be susceptible to a number of diseases. Below are some common diseases that may affect the plant and management options for each:
- Leaf Spot: Leaf spot is a common fungal disease that affects many plants, including Strychnos unguacha A.Rich. var. dschurica Gilg. Infected leaves will exhibit small yellow or brown spots that may merge together and eventually cause the leaf to drop off. Proper sanitation, including removing infected leaves and debris from around the plant, can help prevent the spread of the disease. Fungicides may also be used as a preventative measure.
- Powdery Mildew: Powdery mildew is another fungal disease that affects many plants, including Strychnos unguacha A.Rich. var. dschurica Gilg. Symptoms include a powdery white coating on leaves, stems, and flowers. Good air circulation around the plant can help prevent the disease, as well as removing any infected plant material. Fungicides may also be used to prevent and treat powdery mildew.
- Root Rot: Root rot is a fungal disease that affects the roots of the plant. Symptoms include wilting, yellowing leaves and stunted growth. Overwatering and poorly drained soil can contribute to the disease. To prevent root rot, ensure proper drainage and avoid overwatering the plant. Fungicides may also be applied as a preventative measure.
Pest Management
In addition to disease, Strychnos unguacha A.Rich. var. dschurica Gilg may also be susceptible to a variety of pests. Below are some common pests that may affect the plant and management options for each:
- Aphids: Aphids are small, soft-bodied insects that can cause yellowing and distortion of leaves. They are typically found on the undersides of leaves and can be sprayed off with a strong blast of water. Insecticidal soap can also be used as a treatment.
- Spider Mites: Spider mites are tiny arachnids that can cause stippling of leaves and produce webbing. They prefer dry, dusty conditions and can be controlled by ensuring proper moisture levels and humidity around the plant. Insecticidal soap or neem oil can also be used to control an infestation.
- Mealybugs: Mealybugs are small, white insects that leave a white, cottony residue on the plant. They can be controlled by removing them with a cotton swab dipped in alcohol. Insecticidal soap or neem oil can also be used to control an infestation.
