Origin and Common Names
Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill, commonly known as "Stuhlmann's yam", is a species of flowering plant in the family Dioscoreaceae. It is native to tropical Africa, particularly in East Africa including Tanzania, Kenya, and Uganda. The plant was first described by French botanist Achille Richard in 1847 and was later named after Franz Stuhlmann, a German explorer and botanist who collected the plant in Tanzania in the late 1800s.
General Appearance
Stuhlmann's yam is a climbing vine that can grow up to six meters long. It has a thick, cylindrical, and tuberous root that can weigh up to 20 kilograms. The stem is slender, green, and smooth, while the leaves are heart-shaped with pointed tips and are typically 10 to 30 centimeters long. The plant produces small, greenish-yellow flowers that are arranged in clusters along the stem. The fruit is a three-winged capsule that contains up to six black seeds.
Uses
Stuhlmann's yam is an important food crop in East Africa, where the tubers are boiled or roasted and served as a staple food. The plant has high nutritional value and is rich in carbohydrates, fiber, and various minerals and vitamins. In addition to being used for food, the tubers of the plant are also used for medicinal purposes in traditional African medicine, where they are used to treat various ailments including menstrual disorders, diarrhea, and stomach problems. The plant is also used in agroforestry systems to prevent soil erosion and provide shade for other crops.
Growth Conditions of Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill
Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill is a climbing plant that requires specific growth conditions to thrive. Here are some essential growth conditions:
Light
The plant requires moderate to bright, indirect sunlight for optimal growth. Too much direct sunlight can burn the leaves of the plant, while too little sunlight can cause the leaves to yellow.
Temperature
Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill prefers warm temperatures between 18°C and 27°C. Temperatures below 15°C can cause the plant's growth to slow down or become dormant. It is essential to shield the plant from drafts and sudden temperature changes.
Soil Requirements
The plant thrives in well-draining, fertile soils with a pH range of 6.5 to 7.5. The soil should be rich in organic materials and should not be prone to waterlogging. It is critical to ensure adequate drainage to avoid root rot, which can harm the plant.
In conclusion, ensuring that the growing conditions of Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill are met is essential for the plant's optimal growth and health. The above-discussed elements, including light, temperature, and soil requirements, should be considered when growing this plant.
Cultivation Methods
Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill is a tropical plant that requires a warm and humid environment to thrive. It is best grown in well-draining soil that is rich in organic matter. The plant does well in full sun, but partial shade is also suitable, especially during the hottest parts of the day.
Propagation from cuttings or seeds is possible, with cuttings being the more common method used. Seeds should be planted in a nursery bed and transplanted to their permanent location after approximately six months. Cuttings should be planted directly into their permanent location after being dipped in rooting hormone.
Watering Needs
Watering should be regular but not excessive. The plant prefers moist soil but cannot tolerate waterlogged conditions, which can lead to root rot. During the active growing season, watering should be done two to three times a week, depending on weather conditions and soil drainage. In the dormant season, watering frequency should be reduced to avoid waterlogging.
Fertilization
Fertilization is necessary to maintain plant health, growth, and productivity. The plant requires a balanced fertilizer, such as a 20-20-20 NPK, or a fertilizer high in nitrogen during the vegetative stage. Fertilizer applications should be done every two to three weeks during the growing season. However, It is important to avoid overfertilization, which can lead to excessive vegetative growth, reduced fruiting, and possible nutrient toxicity.
Pruning
Pruning is not necessary for Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill, but it can be beneficial to promote growth and productivity. If pruning is done, It should be done in early Spring before new growth begins. Pruning should involve cutting back the shoots to promote lateral branching and fruiting. Any old or diseased stems should be removed to maintain plant health. Regular monitoring of the plant and pruning selectively to achieve the desired shape and size is recommended.
Propagation of Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill
Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill can be propagated using both vegetative and sexual methods.
Vegitative propagation
The most common vegetative method is through the use of tubers. The tubers are dug up during the dormant season and are cut into sections with each segment having at least one bud. The cuttings are then planted in well-draining soil, with each segment positioned horizontally at a depth of about 5 cm. The plants will establish roots and start growing when the temperature and humidity are suitable.
Sexual propagation
The plant can also be propagated through direct-seeding. The ideal time for direct-seeding is when the rain has started and the soil is still moist. The seeds are collected from fully mature fruits and are sown directly into the soil about 2 cm deep in rows with spacing of 50 cm. Germination will occur between the first and third weeks. The soil must be kept moist to avoid the seeds from drying out.
Seedling transplants can also be used for propagation. Seeds are sowed in seedbeds and the young plants are then transplanted to the field once they reach a proper size.
Disease and Pest Management of Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill
Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill, commonly known as the wild yam, is a tropical plant that is commonly grown for its tuberous roots, which are a good source of food in many parts of the world. The plant is vulnerable to several diseases and pests, which can cause significant damage to the crop if not managed carefully.
Common Diseases:
Anthracnose: Anthracnose is a fungal disease that causes dark, sunken lesions on the leaves, stems, and fruits of the plant. The lesions can spread quickly and cause the plant to wither and die. To manage anthracnose, it is important to remove and destroy all infected plant material and treat the remaining plants with a fungicide.
Leaf Spot: Leaf spot is a fungal disease that causes small, circular lesions on the leaves of the plant. The lesions can merge to form larger, irregularly shaped spots that can cause defoliation. To manage leaf spot, it is important to remove and destroy all infected plant material and treat the remaining plants with a fungicide.
Common Pests:
Root-Knot Nematodes: Root-knot nematodes are microscopic roundworms that can cause significant damage to the roots of the plant. Infected plants may show signs of stunted growth and yellowing leaves. To manage root-knot nematodes, it is important to rotate the crop with non-host plants and treat the soil with a nematicide.
Yam Beetle: Yam beetles are small, black beetles that can cause significant damage to the leaves and stems of the plant. Infected plants may show signs of defoliation and wilting. To manage yam beetles, it is important to apply a suitable insecticide to the plants and their surroundings.
Conclusion:
In conclusion, the management of disease and pests in Dioscorea quartiniana A.Rich. var. stuhlmannii (Harms) Burkill is essential to ensure the healthy growth and development of the plant. It is important to practice good hygiene, remove and destroy all infected plant material, use suitable fungicides and insecticides, and rotate the crop with non-host plants to prevent the buildup of pests and diseases in the soil.
