Introduction
Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill, also known as the African oriental crotalaria, is a plant species belonging to the family Fabaceae. The plant's native range is in Africa, particularly in the eastern and southern regions of the continent.Common Names
The African oriental crotalaria has several common names, including Congo jute, sunn hemp, Madagascan sunn, and Bengal hemp.General Appearance
The plant is an erect, herbaceous annual that can reach a height of up to 3 meters. It has a taproot system, and its leaves are arranged alternately, with a length of 6-12 cm and a width of 2-6 cm. The flowers are yellow and grow in long, slender racemes, which are 20-30 cm in length. The fruit of the plant is a cylindrical pod, which measures up to 15 cm in length and contains several seeds.Uses
The African oriental crotalaria has several practical uses. The plant is used as a source of fiber, and its stems are often used to make rope, twine, and paper. The plant is also considered a valuable forage crop for livestock. Additionally, the plant is known to improve soil fertility and can be used in crop rotation systems to enhance soil productivity. In traditional medicine, certain parts of the plant are used for various ailments. The plant has been used to treat conditions such as fever, cough, and rheumatism. However, caution must be taken when using the plant for medicinal purposes as it can be toxic if consumed in large quantities.Light Requirements
Crotalaria cylindrica A.Rich subsp. afrorientalis Polhill requires full sunlight to flourish. It's a sun-loving plant that is commonly found in open fields, pastures, and other sunny habitats. When grown indoors, it is recommended to provide it with adequate light to mimic natural conditions.
Temperature Requirements
Crotalaria cylindrica A.Rich subsp. afrorientalis Polhill is adapted to tropical and subtropical regions. It grows best in temperatures of 25–32 °C but can tolerate temperatures of up to 40 °C. It's also sensitive to frost and low temperatures, and hence it doesn't thrive in cold climates. The plant requires a warm and humid environment to support optimal growth and productivity.
Soil Requirements
Crotalaria cylindrica A.Rich subsp. afrorientalis Polhill grows well in a wide range of soils but typically performs well in well-draining, loamy soils that are rich in organic matter. The plant's pH tolerance ranges from acidic to neutral, making it suitable for a wide range of soil types. It can also withstand periods of drought but needs regular watering to ensure continuous growth and development.
Cultivation Methods
Crotalaria cylindrica A.Rich. subsp. afrorientalis or the oriental rattlepod is a perennial herb that grows up to one meter high. The ideal soil to grow this plant is well-draining, rich in organic matter, and with a pH range of 5.5 to 7.5. Oriental rattlepods need full sun exposure for optimal growth. These plants can be propagated using seeds or cuttings. If you are growing from seeds, sow them directly into the ground during the rainy season. Oriental rattlepods need six to eight hours of sunlight daily for growth and flowering.Watering Needs
Oriental rattlepods require moderate watering. Water the plants deeply once a week, ensuring that the soil is moist. When the plants establish, reduce watering to once every two weeks. It is essential to avoid overwatering the plants as they are susceptible to root rot. During the rainy season, reduce the frequency of watering.Fertilization
To promote optimal growth and flowering, apply a balanced fertilizer once every two months. Use a fertilizer that has equal quantities of nitrogen, potassium, and phosphorus. Before applying the fertilizer, water the soil around the plants. Avoid applying too much fertilizer as it can cause excess foliage growth and fewer flowers.Pruning
To promote bushy growth, pinch off the tips of young plants when they reach a height of 10-15 cm. Trim off the dead or yellowing leaves and stems to encourage healthy growth. During the flowering season, deadhead or remove faded flowers to promote the growth of new ones. To prevent the plant from self-seeding, cut off the seed pods before they mature.Propagation of Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill
Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill can be propagated through various methods such as seed, stem cuttings, and layering.
Seed propagation
The most common method of propagation is through seeds. These seeds can be sown directly in the field during the rainy season. The seedlings will emerge within 7 to 10 days after planting, and they should be thinned to ensure that each plant has enough space to grow.
For indoor planting, the seeds should be soaked in water for 24 hours before sowing in a mix of compost and sand. The seeds should be covered lightly with soil and kept moist. They will take about 10 to 14 days to germinate, and the seedlings should be transplanted to individual pots once they have two sets of leaves. After the last frost, the seedlings can be planted outdoors.
Stem cuttings
Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill can also be propagated through stem cuttings. The cuttings should be taken from mature healthy plants and should be 6-8 inches long. The bottom leaves should be removed, and the cutting should be dipped in rooting hormone before planting it in a pot with a mix of compost and sand. The cutting should be kept moist and in a warm, shaded area until it develops roots. Once the roots have formed, the cutting can be transplanted outdoors.
Layering
Layering is a propagation technique where a stem is bent to the ground and covered with soil to allow new roots to grow. This technique can also be used for Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill. The stem should be bent to the ground, and a shallow trench should be dug where the stem will be covered with soil. Once the new roots have formed, the stem can be cut from the parent plant and transplanted elsewhere.
Disease Management for Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill
One of the major diseases of Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill is Fusarium wilt. This disease is caused by the soil-borne fungus Fusarium oxysporum f. sp. crotalariae. It leads to wilted plants that eventually die. Crop rotation can help manage the disease. Farmers should avoid planting Crotalaria species in fields that previously had the disease. In addition, practicing good field sanitation can help control Fusarium wilt.
Another disease that affects Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill is leaf spot. The disease is caused by a fungus called Cercospora crotalariae. It leads to yellowish-brown spots on the leaves, which may eventually turn brown and fall off. To manage this disease, farmers can apply fungicides as a preventative measure. Fungicides such as chlorothalonil and mancozeb can help control leaf spot.
Pest Management for Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill
Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill is susceptible to damage from various insect pests. One common pest that attacks this plant is the soybean pod borer, Maruca vitrata. The larvae of this insect bore into the pods of the plant, damaging the seeds and reducing the yield. To control this pest, farmers can use chemical insecticides such as carbaryl or chlorpyrifos. However, it is essential to use these insecticides judiciously, minimizing their negative impact on beneficial insects.
Another insect pest that can affect Crotalaria cylindrica A.Rich. subsp. afrorientalis Polhill is the legume pod borer, Maruca testulalis. This pest can cause significant damage to the crop, leading to reduced yield. Farmers can use biocontrol methods such as releasing parasitoids like Trathala flavoorbitalis, which can help control legume pod borers. Biological control methods can be more effective and sustainable than chemical pesticides in managing insect pests.
