Origin
Strychnos subaquatica De Wild. is a plant species in the family Loganiaceae, native to Africa, particularly the Democratic Republic of Congo, Cameroon and Angola.
Common Names
Some of the common names of Strychnos subaquatica De Wild. include Mukundwe, Kondowe, Lekwe and Nwole.
Uses
The plant has a variety of medicinal uses among African communities. It serves as a natural remedy to treat a range of illnesses such as stomach pain, malaria, toothache, and snakebites. The bark of S. subaquatica is often used as a condiment in food to give it a tangy taste. The timber of the Strychnos subaquatica De Wild. has commercial values as it is durable and has good resistance to pests and rotting.
General Appearance
Strychnos subaquatica De Wild. is an evergreen tree that grows up to 30 meters tall and with a bole diameter of up to 80 cm. The bark is brown-reddish in color with a rough and deeply furrowed texture. The leaves are glossy and leathery, with a rounded or elliptical shape, and arranged alternately along the branches. The flowers are small, white, and fragrant, with a five-pointed star shape. The fruits are spherical or slightly elongated, measuring 2 to 3 cm in diameter, and contain up to four seeds. The outer layer of the fruit is hard, green when fresh but turns yellow when ripe, and splits open to reveal the seeds.
Growth Conditions for Strychnos subaquatica De Wild.
Light Requirements: Strychnos subaquatica De Wild. requires full sunlight to partial shade to grow and thrive. The plant can withstand direct sunlight, but it grows better in partial shade.
Temperature Requirements: This plant prefers tropical to subtropical climates. The optimum temperature range for Strychnos subaquatica De Wild. is between 20°C to 35°C (68°F to 95°F). It cannot withstand frost or cold temperatures and requires high humidity of over 60% to grow well.
Soil Requirements: The plant grows better in well-drained, slightly acidic to neutral soils. It prefers nutrient-rich soils with organic matter content. Sandy soils mixed with organic matter give the best results. However, it can also adapt to a range of soils like loamy, clayey, or sandy soils but does not grow well in heavy, compacted soils.
Water Requirements: Strychnos subaquatica De Wild. requires frequent and consistent watering to maintain its growth and lush green foliage. It is relatively drought-tolerant, but watering should be done during the dry season to prevent drying of the plant. Too much waterlogging can cause root rot, leading to poor growth and development.
Fertilizer Requirements: The use of organic fertilizers like compost, well-rotted manure, and leaf litter can give the best results in the growth and development of Strychnos subaquatica De Wild. It is advisable to use a slow-release fertilizer to avoid the buildup of salinity in the soil.
Propagation: Strychnos subaquatica De Wild. can be propagated through seeds and vegetative propagation methods like stem cuttings, grafting, and air layering. Seed propagation is the most preferred method, and it requires effective seed treatment to break the seed dormancy.
Cultivation Methods
Strychnos subaquatica De Wild., commonly known as the river orange or monkey orange, is a tropical evergreen tree that grows in humid and wet forest regions. The tree requires a warm and humid environment with well-drained, rich soil. It is best grown in areas with a constant temperature and high humidity throughout the year.
Propagation of the plant is mainly through the use of seeds and vegetative cuttings. When using seeds, it is best to soak them in water for 24 hours to increase their germination rate. Vegetative cuttings should be taken from healthy and mature trees for better results.
Watering Needs
Strychnos subaquatica De Wild. requires frequent watering during its growing season, which is usually from spring to autumn. However, it is essential to ensure that the soil is not excessively watered or waterlogged, as this can cause root rot and damage the plant.
Avoid watering the plant during the winter months when it is dormant. Instead, allow the soil to dry out slightly between watering sessions. In general, it is essential to maintain a consistent level of moisture for the tree to thrive.
Fertilization
Regular fertilization is necessary to provide the necessary nutrients for Strychnos subaquatica De Wild. The tree should be fertilized every two to three months during its growing season, which usually begins in spring and ends in autumn.
When fertilizing the plant, it is best to use a balanced, slow-release fertilizer and to apply it at the base of the tree. Ensure that the fertilizer is distributed uniformly around the tree, avoiding direct contact with the trunk.
Pruning
Pruning of Strychnos subaquatica De Wild. is necessary to maintain its shape, promote growth, and remove any dead or diseased branches. The best time to prune the tree is during the winter months when it is dormant.
When pruning, it is essential to use sterile and sharp tools to avoid damaging the tree. Cut back any dead or diseased branches to the nearest healthy branch or section of the tree. Additionally, remove any branches that cross or rub against each other, as this can cause injury to the tree.
Regular pruning helps to improve the overall health and vigor of the tree, resulting in better growth and fruit production.
Propagation of Strychnos subaquatica De Wild.
Strychnos subaquatica De Wild. can be propagated both by seed and vegetatively.
Propagation by Seed
Seeds of Strychnos subaquatica are best collected when they are mature. The seeds should be cleaned and soaked in water for a few days. The soaked seeds should be planted in a well-draining mix in a pot or a seed bed. The seeds can take up to 6 weeks to germinate depending on the temperature and humidity. Once germinated, the seedlings can be transplanted into individual containers or directly into the field.
Vegetative Propagation
Strychnos subaquatica can be propagated vegetatively by stem cuttings and air layering. Stem cuttings should be collected from new growth and should be 10-15cm long. The cuttings should be planted in a well-draining mix and kept in a humid environment until they develop roots. Air layering is another method of vegetative propagation where a section of the stem is wounded and wrapped with moist soil or sphagnum moss and held in place until roots develop. The rooted section is then separated from the mother plant and planted in a container or in the field.
Overall, Strychnos subaquatica De Wild. can be propagated by both seed and vegetative methods. Each method has its advantages, but the success of propagation depends on several factors including the age of the plant, the environment, and the propagation method used.
Disease and Pest Management for Strychnos subaquatica De Wild.
Strychnos subaquatica De Wild. is a medicinal plant that is native to tropical Africa, specifically in Cameroon, Congo, Gabon, and Nigeria. Like any other plant species, it is vulnerable to various diseases and pests that impede its growth and affect its yield. Understanding the common diseases and pests associated with S. subaquatica and their management is crucial for the success of cultivating this plant.
Common Diseases
One of the most prevalent diseases that affect S. subaquatica is leaf spot, which is caused by the fungus Cercospora spp. The symptoms of this disease include numerous small, grayish-brown spots on the leaves, which eventually turn black and cause the leaves to wither. To manage this disease, it is recommended to remove and destroy the affected leaves, avoid overhead irrigation, and apply fungicides.
Another common disease that attacks S. subaquatica is root rot, which is caused by the soil-borne fungus Phytophthora spp. This disease is characterized by the rotting of the roots, which results in stunted growth and wilting of the above-ground parts of the plant. To prevent this disease from spreading, it is crucial to provide proper drainage and avoid waterlogging the soil. The use of fungicides may also help manage this disease.
Common Pests
The two most damaging pests that affect S. subaquatica are stem borers and leafhoppers. Stem borers are the larvae of insects that bore into the stems, causing girdling and eventual death of the plant. To control this pest, it is essential to inspect the plants regularly and remove the affected stems. Additionally, applying insecticides may also help manage this pest.
Leafhoppers, on the other hand, are small, sap-sucking insects that feed on the leaves, causing stunted growth and yellowing of the leaves. To manage this pest, it is important to monitor the plants and apply insecticides if necessary. Additionally, the use of reflective mulch or floating row covers may also deter the leafhoppers from attacking the plants.
In conclusion, disease and pest management are critical components of cultivating S. subaquatica. By implementing proper management practices, growers can reduce the impact of diseases and pests on the plant's health and achieve optimal yields.
