Overview:
Colocasia esculenta (L.) Schott var. aquatilis Hassk. is a perennial aquatic plant that belongs to the family Araceae. It is also commonly known as Elephant Ear or Taro. It is widely cultivated in Southeast Asia, Oceania, and other tropical and subtropical regions of the world for its edible corms and leaves.
Appearance:
The plant has broad, heart-shaped leaves that grow up to 1 meter in length and 50-75 cm wide. The leaves are green in color and have prominent veins. The corms are approximately 5-10 cm in diameter and covered with a brownish sheath. The flowers are small and are clustered at the base of the leaf stalk. The fruit is small and contains several small seeds.
Origin:
The plant is believed to have originated in Southeast Asia, particularly in India and Malaysia. It has been cultivated in these regions for thousands of years for its food and medicinal uses. It has also spread to other tropical regions including Africa, South America, and the Caribbean.
Common Names:
Colocasia esculenta is commonly known by different names in different regions. In Southeast Asia, it is known as Taro or Dasheen. In West Africa, it is called Cocoyam or Eddoe. In South America, it is known as Malanga and in the Caribbean, it is known as Eddo or Coco.
Uses:
The plant has multiple uses. The corms are the most commonly used part of the plant and are consumed as a staple food in many cultures. They can be boiled, roasted, fried, or baked and are used in a variety of dishes such as stews, soups, and dumplings. The leaves are also edible and are used in many dishes, including as a wrap for various foods. They are also used for medicinal purposes as they contain high levels of antioxidants and anti-inflammatory properties. The plant is also commonly used for ornamental purposes and is grown for its attractive leaves in gardens and landscapes.
Light Requirements
Colocasia esculenta var. aquatilis Hassk., also known as water colocasia, prefers full sunlight to partial shade. However, excessive direct sunlight may harm the plant.
Temperature Requirements
The plant grows best in warm temperatures, ranging between 26°C and 35°C. The minimum temperature required for the plant's growth is around 21°C. Anything below this temperature may slow down the growth.
Soil Requirements
The water colocasia grows best in well-drained, fertile soils. The soil should be rich in organic matter and slightly acidic or neutral, with a pH range between 5.5 and 7.5. The soil should also be continuously moist; however, it should not be waterlogged, as this can cause root rot and lead to plant death.
Cultivation Method for Colocasia Esculenta (L.) Schott var. Aquatilis Hassk.
Colocasia esculenta var. aquatilis is commonly known as water colocasia. It is a semi-aquatic plant and needs to be cultivated in a wet environment. The plant grows well in waterlogged or swampy areas. It requires a slightly acidic soil pH between 6.0 and 6.7 for optimal growth. Colocasia aquatilis can tolerate partial shade and full sun exposure, but it prefers partial shade. When planting, ensure the soil is rich in organic matter. Also, plant at a depth of 10 cm to prevent drying out.
Watering Needs
Colocasia aquatilis needs to be constantly moist to promote optimal growth. The plant can survive well in standing water as long as the water remains within its tolerance level. However, avoid overwatering as it may lead to rotting of the tubers. Regularly check the soil moisture and add water when necessary.
Fertilization
Colocasia aquatilis requires regular fertilization for healthy growth. Add organic matter such as compost and manure to the soil before planting. Apply a balanced fertilizer with micronutrients during the growing season to promote healthy foliage and root growth. Fertilize the plant every six to eight weeks during the active growing season such as summer and spring.
Pruning
Colocasia aquatilis requires minimal pruning as it grows naturally. You can remove yellowed or damaged leaves by cutting them at the base of the petiole. Pruning should be done regularly to maintain good airflow and prevent fungal and bacterial diseases. Remove any unwanted suckers by cutting them at the soil level.
Propagation of Colocasia esculenta (L.) Schott var. aquatilis Hassk.
Propagation is the process of generating offspring or new plants from the parent plant. Colocasia esculenta (L.) Schott var. aquatilis Hassk. can be propagated through the following methods:
Seed Propagation
Colocasia esculenta (L.) Schott var. aquatilis Hassk. can be propagated through seeds. The seeds are collected, cleaned, and dried before being sown in the field. The recommended spacing for the seedlings is 1.5 feet to 2 feet, and a depth of 1 inch. The seeds germinate within 7 to 10 days, and the seedlings take about 6 to 8 months to mature. Seed propagation is a slow and unreliable method of propagation.
Corm Division
Corm division is the most common and efficient method of propagating Colocasia esculenta (L.) Schott var. aquatilis Hassk. It involves separating the corm into smaller sections, with each section having at least one bud, or growing point. The corm sections are planted in a well-prepared field, with a spacing of 3 to 4 feet between each plant. Corm division is usually done during the dormant season, either just before the rainy season or just after the harvesting season.
Vegetative Propagation
Colocasia esculenta (L.) Schott var. aquatilis Hassk. can also be propagated through vegetative means such as stem cuttings or suckers. Stem cuttings are taken from mature plants, cut into 6-inch to 8-inch sections, and planted in well-prepared soil. The cuttings should be planted in such a way that one-third of the section is above the soil level. Suckers, which are small plantlets growing from the corm, can be removed carefully and planted.
Overall, corm division is the most efficient and recommended method of propagating Colocasia esculenta (L.) Schott var. aquatilis Hassk. It is less prone to disease transmission and ensures uniform plants, which are essential in commercial production.
Disease Management for Colocasia Esculenta
Colocasia esculenta is prone to various diseases that can pose a threat to its growth and yield. Here are some common diseases and ways to manage them:
Phytophthora Leaf Blight
Phytophthora leaf blight can affect the leaves, stems, and roots of Colocasia esculenta. Symptoms include yellowing and wilting of leaves, root rot, and stunted growth. To manage this disease, it is advisable to use clean water and soil when planting the crop. Also, practice crop rotation, avoid over-fertilizing, and use resistant varieties.
Dasheen Mosaic Virus
Dasheen mosaic virus causes mottled leaves and stunted growth. It can also lead to the deformation of leaves. To prevent this viral infection, always ensure to plant clean and disease-free bulbs. Also, avoid planting in fields that have a history of the virus, control aphids, which spread the virus, and remove infected plants immediately.
Root Knot Nematodes
Root knot nematodes can cause significant damage to Colocasia esculenta by attacking the roots, leading to poor growth. The nematodes can also cause discoloration and distortion of leaves. To manage this disease, it is advisable to use resistant varieties, practice crop rotation, and improve soil structure and hygiene by intercropping with non-host crops.
Pest Management for Colocasia Esculenta
Colocasia esculenta is also prone to pests that can cause significant damage to the plant. Here are some common pests and ways to manage them:
Spider Mites
Spider mites can cause yellowing, stippling, and webbing on leaves. They also suck plant sap, leading to stunted growth. To manage spider mites, keep the fields clean, use mulch to maintain moisture levels, and use insecticidal soap or oil sprays to control populations.
Cutworms
Cutworms are larvae of moths that attack young Colocasia esculenta plants, cutting them at the base and killing them. To prevent the attack of cutworms, use physical barriers such as collars around the plants, handpick them at night, and avoid planting near old plant debris, which harbors cutworms.
Armyworms
Armyworms can cause severe damage to Colocasia esculenta plantations by feeding voraciously on young plants and mature leaves. To prevent armyworm attacks, use insecticide sprays, practice crop rotation, and use pheromone traps to monitor their populations and prevent mating.
