Origin and Common Names
Dialium quinquepetalum Pellegr., also known as Suan in the local language, is a species of plant in the family of Fabaceae. This plant is native to Central Africa and can be found in countries such as Cameroon, Gabon, and Congo-Brazzaville.
Uses
The Dialium quinquepetalum plant is highly valued for its medicinal properties. The bark is used to treat various ailments such as fever, diarrhea, and cough. The leaves and roots have anti-inflammatory and diuretic properties, useful for treating rheumatism and edema, respectively.
Additionally, the fruit of the Dialium quinquepetalum plant is edible and is used in traditional African cuisine. The fruits are a rich source of vitamin C, calcium, and iron, making them a valuable addition to the diet. They can be eaten raw or cooked, and are also used to prepare a local beverage called tangy juice.
General Appearance
The Dialium quinquepetalum plant is a small to medium-sized tree, growing up to 15m tall with a trunk that can reach up to 50 cm in diameter. The bark is smooth and grey-brown in color. The leaves are alternate, compound, and imparipinnate, with 5-7 leaflets. The leaflets are ovate to elliptical in shape and have a leathery texture. The flowers are small, pale yellow, and are borne in clusters at the end of the branches. The fruits of the Dialium quinquepetalum plant are drupes, about the size of a cherry, and have a hard, woody shell. They contain one large seed, which is edible and has a sweet and slightly sour taste.
Light Requirements
The Dialium quinquepetalum plant typically requires partial to full sunlight exposure to grow well. It thrives in areas with bright, indirect light exposure, preferably receiving sunlight in the morning but shaded in the afternoon. Direct sunlight exposure for extended periods may cause leaf burn and stunted growth.
Temperature Requirements
The ideal temperature range for the growth and development of Dialium quinquepetalum ranges from 20°C to 30°C. The plant can tolerate temperatures above this range provided there is adequate moisture in the soil. Extremely high temperatures can cause wilting or even death of young plants. Low temperatures below 5°C can cause leaf drop and slow down growth.
Soil Requirements
The Dialium quinquepetalum plant prefers well-draining soils with rich organic matter content. The soil must be loose, deep, and well-aerated. It can grow in a wide range of soil types, including loamy, sandy loam, and clay. However, the plant does not thrive in waterlogged or dry soil conditions. The pH level of the soil should range from 6.0 to 7.5, which is slightly acidic to neutral. Proper soil preparation and drainage are essential to prevent root rot and waterlogging.
Cultivation methods
Dialium quinquepetalum Pellegr., also known as Black Velvet, is a tropical tree that prefers a warm climate with a temperature range of 20-35°C. It is generally grown from seeds that require pre-sowing treatment. Before sowing, the seed should be soaked in hot water overnight to soften the seed coat and promote germination. Sow the seeds in a well-draining potting mix and place them in a warm and humid location. The seedling should be transplanted into the main field in about six months when it reaches a height of about 30 cm.
Watering needs
Dialium quinquepetalum Pellegr. prefers a moist but well-draining soil. During the active growth period, it requires regular watering. However, overwatering should be avoided, as it can lead to root rot. Allow the soil to dry slightly between watering to prevent waterlogging, especially in the rainy season. It is essential to adjust the watering schedule according to the climate and individual plant needs.
Fertilization
To promote a healthy growth rate, Dialium quinquepetalum Pellegr. requires regular fertilization. During the growing season, use a balanced fertilizer that contains equal amounts of nitrogen, phosphorus, and potassium, along with micronutrients like iron, manganese, and zinc. Application of organic manure also helps to improve the soil's fertility and structure, leading to healthy growth.
Pruning
Pruning is essential to maintain the tree's shape and health. It is best to prune during the dormant season, i.e., winter, from December to February. Dead, diseased, and weak branches should be removed, leaving only the healthy ones. Pruning should be done appropriately, avoiding severe cuts, as they can lead to stress and susceptibility to pests and diseases. Additionally, regular pruning improves the quality and quantity of fruit production.
Propagation of Dialium quinquepetalum Pellegr.
Dialium quinquepetalum Pellegr. can be propagated through various methods. The following are some of the most common propagation methods:
Seed Propagation
Seeds are a cost-effective method of propagation. They can be collected from ripe fruits and cleaned before sowing. The seeds should be sown in well-draining soil with a mixture of sand and compost. Cover the seeds with a light layer of soil and water regularly to keep the soil moist. Germination can take up to 4 weeks.
Cuttings Propagation
Cuttings propagation is another effective way to propagate Dialium quinquepetalum Pellegr. Take cuttings of 15-20 cm length from semi-hardwood stems. Ensure that at least 2-3 nodes are present on the cutting. Treat the lower end of the cutting with rooting hormone before planting in well-draining soil. Water the cuttings regularly and provide partial shade for optimal growth.
Air Layering Propagation
Air layering is a common propagation method for Dialium quinquepetalum Pellegr. Choose a healthy branch from the parent plant and cut off a 2-3 cm strip of bark from the middle of the branch. Apply rooting hormone in the exposed area and wrap it with moist sphagnum moss or peat moss. Cover the moss with plastic wrap to keep it moist and secure it with twine or a rubber band. Roots will start to form in about 3-4 weeks. Once roots have developed, cut the branch below the moss, plant it in soil, and water it regularly.
Disease and Pest Management for Dialium quinquepetalum Pellegr.
Dialium quinquepetalum Pellegr., commonly known as the black velvet tamarind, is a tree species native to Africa. It is grown for its edible fruit and also serves as an ornamental plant. However, like any other plant, it is susceptible to diseases and pest infestations that can damage its growth and yield. In this article, we will discuss the common diseases and pests that affect Dialium quinquepetalum and suggest ways to manage them.
Common Diseases
1. Anthracnose: This disease is caused by the fungus Colletotrichum gloeosporioides. It affects the leaves, stems, and fruits of the plant, causing dark, sunken lesions. It can lead to defoliation, premature fruit drop, and reduced yield. To manage anthracnose, remove and destroy infected plant debris. Apply fungicides containing copper to protect the plant from further infection.
2. Leaf spot: Leaf spot is caused by the fungus Cercospora spp. It causes small, circular spots on the leaves that can merge into large, irregular lesions. The affected leaves turn yellow and drop prematurely. To manage leaf spot, remove and destroy infected leaves. Improve air circulation by pruning overcrowded branches. Apply fungicides containing copper to protect the plant from further infection.
Common Pests
1. Ambrosia beetle: The ambrosia beetle attacks weakened or stressed plants, including Dialium quinquepetalum. It bores into the trunk and creates tunnels where it lays its eggs. This can lead to girdling of the tree, causing wilting and death. To manage ambrosia beetle, maintain tree vigor through proper cultural practices such as watering and fertilization. Treat infested trees with insecticide containing carbaryl.
2. Fruit fly: The fruit fly is a common pest that affects Dialium quinquepetalum fruit. The adult female lays eggs in the fruit, and the larvae feed on the pulp. This can lead to fruit rot and reduced yield. To manage fruit fly, remove and destroy infested fruit. Use pheromone traps to monitor the population. Apply insecticide containing spinosad or deltamethrin to protect the fruit from further infestation.
In conclusion, Dialium quinquepetalum Pellegr. can suffer from diseases and pest infestations that can damage its growth and yield. However, with proper disease and pest management practices, it is possible to protect the plant from further damage and ensure its healthy growth and development.
