Overview
Dioscorea hirticaulis Bartlett, also known as hairy yam, is a species of yam native to Africa. It is a perennial plant that is widely cultivated for its edible tubers. The plant belongs to the family Dioscoreaceae and is closely related to other yam species such as Dioscorea alata and Dioscorea rotundata.
Appearance
The hairy yam is a climbing vine that can reach up to 6 meters in height. The stems are woody and may be twisted or branched. The leaves are alternate, heart-shaped, and sometimes lobed. The plant produces small, greenish-yellow flowers that are arranged in clusters. The fruit is a capsule that contains many seeds, each surrounded by a fleshy aril.
Common Names
The Dioscorea hirticaulis is commonly known as the hairy yam, African yam, and bitter yam.
Uses
The tubers of the hairy yam are an important food source in many parts of Africa. They are high in carbohydrates and can be prepared in many ways, including roasting, boiling, or frying. The leaves are also used as a vegetable and can be cooked like spinach or added to soups and stews. In traditional medicine, the yam is used to treat various ailments such as digestive problems, fever, and constipation. The plant's extract is also used in cosmetics and soap-making.
Light Conditions
Dioscorea hirticaulis Bartlett thrives in areas with plenty of sunlight. This plant requires at least 6 hours of direct sunlight daily, making it an ideal choice for planting in areas with full sun exposure. Adequate sunshine promotes optimal growth and enhances its natural beauty.
Temperature Requirements
Dioscorea hirticaulis Bartlett prefers warm temperatures and cannot tolerate frost. The optimal growth temperature range for the plant is between 20 and 30°C. Cold temperatures below 10°C can lead to stunted growth or death of the plant. Additionally, hot temperatures above 35°C can also cause damage to the plant.
Soil Requirements
The plant does well in well-draining soils that are rich in organic matter. It prefers fertile soils with high moisture and nutrient retention capabilities. Additionally, pH levels should fall within the range of 5.0 and 6.5, which refers to soil with a slightly acidic nature. The plant can be vulnerable to waterlogged soils and soil with poor drainage.
Cultivation Methods for Dioscorea hirticaulis Bartlett
Dioscorea hirticaulis Bartlett, commonly known as the hairy yam, can be cultivated either through seed or vegetative propagation. Propagation using smaller tubers is more common, as larger ones have a lower sprouting success rate. The plant grows best in a soil pH of 5.5 to 6.5 and in areas with well-draining soil. It requires a warm, humid environment and can grow in both full sun and partial shade.
Watering Needs for Dioscorea hirticaulis Bartlett
The hairy yam requires regular watering, especially during the growing season, to keep the soil moist. Under-watering could result in reduced yields, while over-watering could cause rotting of the tubers or even death of the plant. Mulching around the base of the plant can help retain moisture and suppress weed growth.
Fertilization of Dioscorea hirticaulis Bartlett
Dioscorea hirticaulis Bartlett responds well to fertilizers high in nitrogen and potassium, which can increase both the size and number of tubers produced. Fertilizer should be applied during the growing season, ideally at least once a month, using a combination of organic and inorganic fertilizers.
Pruning of Dioscorea hirticaulis Bartlett
To encourage better branching and increased tuber production, pruning is recommended. Pruning should be carried out after tuber formation and after the plant has died down naturally. Remove diseased, damaged or dead leaves and stems, and allow the healthy ones to remain.
Propagation of Dioscorea hirticaulis Bartlett
Dioscorea hirticaulis Bartlett, commonly known as the hairy yam, is a popular staple food crop in West and Central Africa. Propagation of Dioscorea hirticaulis Bartlett can be achieved by various methods including:
Vegetative propagation
This is the most common method used in the propagation of Dioscorea hirticaulis Bartlett. It involves the use of plant parts such as tubers, bulbils, and vine cuttings.
Tubers: The most commonly used method of propagation is through tubers. Tubers are cut into small pieces of approximately 50 g each and each piece is planted individually. The tubers should be planted in well-drained soil and should be covered with a layer of soil about 5 cm thick. Ensure that the soil is moist but not waterlogged.
Bulbils: Bulbils are small, aerial tubers that form at the base of the stem of the plant. They can be used to propagate new plants. The bulbils are removed from the stem and planted in well-drained soil. The soil should be kept moist but not waterlogged.
Vine cuttings: Vine cuttings from the plant can also be used to propagate Dioscorea hirticaulis Bartlett. The cuttings should be taken from well-developed vines and should be planted in well-drained soil. The base of the cutting should be placed in the soil at a depth of about 5 cm and the soil should be kept moist but not waterlogged.
Seed propagation
Dioscorea hirticaulis Bartlett can also be propagated from seeds, but this method is not commonly used because the seeds are rare and difficult to obtain. The seeds are usually produced after the flowers have been pollinated, and they take several months to mature. Once the seeds have matured, they can be collected and planted in well-drained soil. The soil should be kept moist, and the seedlings should be protected from direct sunlight until they are well-established.
In conclusion, vegetative propagation is the most common and efficient method of propagating Dioscorea hirticaulis Bartlett. It requires less time and effort and produces plants that are genetically identical to the parent plant. Seed propagation, on the other hand, is time-consuming and produces plants that are not identical to the parent plant.
Disease and Pest Management for Dioscorea hirticaulis Bartlett
Dioscorea hirticaulis Bartlett is a tuberous plant that belongs to the Dioscoreaceae family. The plant is relatively easy to grow, but it can be susceptible to diseases and pests. The following are some of the common diseases and pests that affect Dioscorea hirticaulis Bartlett and how to manage them effectively.
Common Diseases Affecting Dioscorea hirticaulis Bartlett
Root Rot: This is a common disease that affects Dioscorea hirticaulis Bartlett. It is caused by a fungus, and it affects the roots of the plant, leading to decay. Symptoms of root rot include yellowing of leaves, wilting, and stunted growth. To manage this disease, remove the affected plants and dispose of them properly. Also, ensure proper drainage, avoid overwatering, and use fungicides in severe cases.
Leaf Blight: This is another common disease that affects Dioscorea hirticaulis Bartlett. It is caused by fungal pathogens and affects the leaves of the plant. Symptoms of leaf blight include the appearance of lesions and spots on the leaves, which turn yellow and fall off. To manage this disease, prune the affected leaves, avoid overhead irrigation, and use fungicides in severe cases.
Common Pests Affecting Dioscorea hirticaulis Bartlett
Root Knot Nematodes: These are microscopic worms that affect the roots of the plant, leading to stunted growth and decreased yield. To manage this pest, rotate crops, use resistant cultivars, and apply nematicides.
Cutworms: These are larvae of certain moth species that cut off the plants' stems at or below the soil surface. To manage this pest, use physical barriers, such as collars made of cardboard or plastic, and apply insecticides.
Beetles: There are several beetle species that can affect Dioscorea hirticaulis Bartlett, such as flea beetles and leaf beetles. These pests feed on the leaves of the plant, leading to defoliation and decreased yield. To manage this pest, use insecticides and practice good sanitation, such as removing plant debris from the field.
In conclusion, Dioscorea hirticaulis Bartlett is a tuberous plant that can be affected by several diseases and pests. Proper crop management practices, such as crop rotation, sanitation, and the use of resistant cultivars and pesticides, can help manage these problems effectively, leading to higher yields and improved crop health.
