Overview
Striga schimperiana Hochst. ex A.Rich., also known as Purple Witchweed, is a parasitic plant belonging to the family Orobanchaceae. This plant is native to Africa, specifically in the tropical and subtropical regions of East and West Africa.
Common Names
Aside from Purple Witchweed, Striga schimperiana is also known by other common names such as African Witchweed, Schimper's Witchweed, Ethiopian Witchweed, and Tropical Witchweed.
Appearance
Striga schimperiana is a slender, leafless, and parasitic plant that grows up to 50 cm tall. The stem of the plant is purple in color with numerous small branches and small yellow flowers. The plant also produces small capsules containing seeds that can easily spread through the wind or by attaching themselves onto animals or humans, making it a dangerous weed especially to crops such as maize and sorghum.
Uses
Despite its parasitic and harmful nature to other plants, Striga schimperiana is known for its medicinal properties. The plant contains bioactive compounds that possess antimicrobial, antifungal, and antioxidant properties, making it useful in traditional medicine for treating various illnesses such as coughs, bronchitis, and rheumatism. However, the plant should be used with caution and under the guidance of a medical professional due to its parasitic nature and potential toxicity.
Light Requirements
Striga schimperiana Hochst. ex A.Rich. is a parasitic plant that requires a host plant for survival. It does not have specific light requirements as it obtains its nutrients from the host plant. However, the host plant should be exposed to adequate sunlight to facilitate photosynthesis and make nutrients available to the parasite.
Temperature Requirements
This plant thrives in tropical and subtropical regions, including areas with warm temperatures between 20°C to 30°C. It can also tolerate high temperatures of up to 45°C for a short period. Low temperatures below 10°C limit the germination and growth of Striga schimperiana Hochst. ex A.Rich.
Soil Requirements
Striga schimperiana Hochst. ex A.Rich. grows in a range of soil types, including sandy, loamy, and clay soils. However, it prefers well-drained soil with a neutral pH of between 6 and 7. It cannot survive in waterlogged soils. Due to its parasitic nature, the plant requires a host plant for optimal growth, and the type of host plant affects soil requirements. Some host plants such as maize and sorghum thrive in sandy soils, while others such as soybean prefer loamy soils.
Cultivation of Striga schimperiana Hochst. ex A.Rich.
Striga schimperiana is a parasitic plant that attaches itself to the roots of other plants. Therefore, it should not be cultivated in the same planting with other crops.
Striga schimperiana prefers to grow in areas with well-draining and fertile soil. It thrives in a warm and humid climate with temperatures ranging from 25°C to 30°C. However, it can also grow in cooler temperatures, but growth is slower.
The ideal time to sow the seeds of Striga schimperiana is at the beginning of the rainy season, typically around March to April.
Watering Needs of Striga schimperiana Hochst. ex A.Rich.
Striga schimperiana requires regular watering, but care should be taken to avoid water-logging the soil as it can lead to root rot.
The frequency of watering depends on the weather conditions and the drainage of the soil. During dry spells, Striga schimperiana should be watered more frequently to keep the soil moist.
Fertilization of Striga schimperiana Hochst. ex A.Rich.
Striga schimperiana does not require fertilization as it is a parasitic plant. However, it is important to maintain the fertility of the soil to provide other beneficial plants with nutrients.
Organic matter such as compost or manure should be added to the soil periodically to maintain its fertility.
Pruning of Striga schimperiana Hochst. ex A.Rich.
Striga schimperiana does not require pruning as it is a parasitic plant that does not produce any above-ground structures.
However, any infected plants should be removed immediately to prevent the spread of the parasite to other beneficial plants.
Propagation of Striga schimperiana Hochst. ex A.Rich.
Striga schimperiana Hochst. ex A.Rich. can be propagated through both seeds and vegetative means.
Seed propagation
Seeds from the plant can be collected when the capsules turn brown and start to split open. The seeds must be separated from the capsule and allowed to dry in a shaded and well-ventilated area. The dried seeds can be sown in a mixture of soil and sand, and kept moist with regular watering. Germination of the seeds usually occurs within 2-3 weeks, and the seedlings can be transplanted to a bigger container or directly to the ground when they are few inches tall.
Vegetative propagation
Striga schimperiana Hochst. ex A.Rich. can also be propagated through vegetative means such as stem cuttings or root cuttings. For stem cuttings, cut a healthy stem from the parent plant that is a few inches long and remove the lower leaves. Dip the cut end in rooting hormone and plant the cutting in a pot or container with well-draining soil. Water the cutting regularly and keep it in a shaded area until new growth appears. For root cuttings, select a few healthy roots from the parent plant and cut them into sections a few inches long. Plant the sections in a pot or container with well-draining soil and water regularly. New growth should appear within a few weeks, at which point the new plant can be transplanted to a bigger container or directly to the ground.
Disease Management
Striga schimperiana Hochst. ex A.Rich. is susceptible to various diseases that can affect its growth and yield. The most common diseases that affect this plant are:
- Root rot: This is a fungal disease that affects the root system of the plant, leading to the death of the plant. To prevent this disease, ensure that the plant is grown in well-draining soil and avoid overwatering.
- Leaf spot: This is a fungal disease that affects the leaves of the plant, causing the leaves to have spots. To prevent this disease, avoid overcrowding of plants and ensure proper ventilation.
- Powdery mildew: This is a fungal disease that affects the leaves of the plant, causing a white powdery substance to appear on the leaves. To prevent this disease, ensure that plants are not overcrowded, and provide proper ventilation.
To manage these diseases, it is essential to practice good crop hygiene, remove infected plant material, and avoid overwatering. In severe cases, it may be necessary to use fungicides, but this should be done as a last resort.
Pest Management
Striga schimperiana Hochst. ex A.Rich. can also be affected by pests that can cause significant damage to the plant. Some common pests that affect this plant include:
- Leafhoppers: These pests feed on the sap of the plant, causing yellowing of leaves and stunted growth. To prevent this, remove weeds around the plant and use insecticides if necessary.
- Spider mites: These pests also feed on the sap of the plant, causing yellowing of leaves and webbing. To prevent this, ensure the plant is adequately watered and remove any infested plant material.
- Aphids: These pests suck the sap from the plant, which can lead to stunted growth. To prevent this, avoid over-fertilizing the plant, remove any infected plant material, and use insecticides if necessary.
To manage these pests, it is essential to practice good crop hygiene, remove any infected plant material, and use insecticides if necessary. It is also necessary to monitor the plant regularly for signs of pest infestation.
