Overview of Citrullus vulgaris Schrad.
Citrullus vulgaris Schrad., commonly known as watermelon, is a flowering plant that belongs to the cucumber family. It is native to Southern Africa but is now cultivated globally in tropical and sub-tropical areas for its juicy, sweet fruit.
Common Names for Citrullus vulgaris Schrad.
Aside from watermelon, the plant is also referred to by other common names, such as:
- Wild watermelon
- Desert watermelon
- West African watermelon
- Citrullus
Appearance of Citrullus vulgaris Schrad.
The plant has a vining growth habit and can spread up to 10 feet long. Its leaves are lobed and somewhat hairy, while the flowers are yellow and grow in clusters. The fruit of the watermelon plant is round or oblong, and its rind can range in color from light green to dark green with stripes or spots. The juicy, sweet flesh inside can vary in color, from red and pink to yellow and white, and contains numerous black seeds.
Uses of Citrullus vulgaris Schrad.
Citrullus vulgaris Schrad. is primarily cultivated for its fruit, which is enjoyed fresh or processed into juice, jam, and pickles. Moreover, its seed kernels are edible and can be roasted and seasoned like pumpkin seeds. In traditional medicine, watermelon is purported to have diuretic, cooling, and anti-inflammatory properties, among others.
Moreover, watermelon is also used decoratively in some cultures and is sometimes carved into sculptures or used as a makeshift container.
Light Requirements
Citrullus vulgaris Schrad. requires full sun exposure for optimal growth and fruit production. A minimum of six hours of direct sunlight is necessary each day. The absence of sufficient sunlight will result in poor overall growth and smaller fruit.
Temperature Requirements
Citrullus vulgaris Schrad. is a warm-season crop and requires warm temperatures to grow. The optimum temperature range for growth is between 22°C-32°C. Temperatures below 16°C can impact fruit quality, and temperatures below 11°C can be fatal. High humidity levels can also lead to disease development and fruit cracking.
Soil Requirements
Citrullus vulgaris Schrad. prefer well-draining soils that are rich in organic matter with a pH ranging from 6.0-6.5. The plant can tolerate a wide range of soil types, but it thrives in loamy soils with good drainage. Adding compost or aged manure can improve soil fertility and provide essential nutrients for growth. The soil temperature must be between 20°C-25°C for seeds to germinate correctly.
Cultivation methods
Citrullus vulgaris Schrad., commonly known as watermelon, is a warm-season crop that thrives in well-drained soils with a pH ranging from 6.0 to 6.8. The plant requires full sunlight exposure for optimum growth and development. The ideal temperature for seed germination is between 25°C to 35°C. Watermelons can be grown using direct seeding or transplants.
Watering needs
Watermelon is a water-loving plant that requires frequent watering throughout the growing season. The plant needs an inch of water per week to develop strong roots, healthy foliage, and well-formed fruits. However, be careful not to overwater the plant as excess water can lead to root rot and other fungal diseases. It is advisable to water the soil in the morning to prevent waterlogged conditions during the night.
Fertilization
Watermelons are heavy feeders that require high levels of nutrients to produce large and sweet fruits. It is recommended to use well-composted manure or organic fertilizers such as bone meal, blood meal, and fish emulsion to provide the plant with sufficient nutrients. A balanced fertilizer with an N-P-K ratio of 4-4-4 is also suitable for watermelon cultivation.
Pruning
Pruning is an essential practice that involves removing excess foliage and secondary shoots to improve air circulation and sunlight penetration in the plant canopy. The primary stem of the watermelon plant should be left intact, and only the lateral shoots should be pruned. The pruning should be done when the plant develops two to three true leaves, and the lateral shoots are about three inches long. This practice helps to reduce the competition for nutrients and water, resulting in larger and sweeter fruits.
Propagation of Citrullus vulgaris Schrad.
Citrullus vulgaris Schrad., commonly known as watermelon, is a sweet and juicy crop grown for its edible fruit. It is propagated both sexually and asexually to yield a higher quantity of fruit-bearing plants.
Sexual Propagation
Sexual propagation of Citrullus vulgaris Schrad. involves the use of seeds produced from sexually mature plants. The seeds can be obtained either from F1 hybrid, open-pollinated, or self-pollinated plants. Sexual propagation is a cost-effective method, and the resulting plants are genetically diverse. The seeds are sown at a depth of 2-4 cm in well-drained soil with good organic matter content and slightly acidic pH. The seeds usually germinate within 5-10 days at a temperature of 25-30 °C.
Asexual Propagation
Asexual propagation methods are commonly used to obtain true-to-type plants with identical genetic makeup to that of the parent plant. Two popular asexual propagation methods for Citrullus vulgaris Schrad. are stem cuttings and tissue culture.
Stem cuttings: The stem cuttings are collected from mature plants in the early morning and dipped in hormone rooting powder. The cuttings are planted in well-drained soil, and the soil is kept moist. The cuttings develop roots in 2-3 weeks, and once the roots are established, the plants can be transplanted in the field.
Tissue Culture: Tissue culture is a more advanced method of propagation that involves the use of plant tissue to produce multiple genetically identical clones. In this method, small pieces of plant tissue, such as leaves or shoot tips, are taken from selected plants and placed in a nutrient-rich culture medium. The plants are grown in sterile conditions with controlled humidity, light, and temperature. After several weeks, the tissue culture produces multiple shoots and roots, which are transplanted in the field.
Both sexual and asexual propagation methods can be used for Citrullus vulgaris Schrad., depending on the objectives of the grower. With proper attention to the methods employed, it is possible to propagate healthy plants with high-quality fruit.
Disease and Pest Management for Citrullus vulgaris Schrad. Plants
Citrullus vulgaris Schrad. is a plant species that is commonly known as watermelon. It is a popular crop, but it is susceptible to certain diseases and pests that can adversely affect yield and quality. Being a gardener or farmer, it is important to understand the most common diseases and pests that can afflict the watermelon plant and ways to manage them.
Common Diseases Affecting Citrullus vulgaris Schrad.
1. Anthracnose: Anthracnose is a fungal disease that affects the leaves, stems, and fruit of the watermelon plant. Symptoms include brown, sunken lesions on the fruit, and yellowing and wilting of the leaves. To manage anthracnose, you should use disease-free seeds, avoid overhead irrigation, and apply fungicides before and after flowering.
2. Fusarium Wilt: Fusarium wilt is a soil-borne fungal disease that causes yellowing and wilting of the leaves and stunted growth of the watermelon plant. The fungus can persist in the soil for several years, so crop rotation is essential to avoid the disease. You can also use resistant varieties of watermelon and treat the soil with biocontrol agents or fungicides.
3. Gummy Stem Blight: Gummy stem blight is a fungal disease that affects the stem, leaves, and fruit of the watermelon plant. Symptoms include black or brown spots on the leaves and water-soaked lesions on the stem. You can manage gummy stem blight by using disease-free seeds, avoiding overhead irrigation, and applying fungicides before and after flowering.
Common Pests Affecting Citrullus vulgaris Schrad.
1. Aphids: Aphids are small insects that suck the sap from the leaves and stem of the watermelon plant, causing them to curl and yellow. They also excrete a sticky substance that attracts ants and can lead to the growth of sooty mold. You can manage aphids by using insecticidal soap, neem oil, or horticultural oils as well as by encouraging natural predators like ladybugs and lacewings.
2. Cutworms: Cutworms are moth larvae that live in the soil and feed on the stem of the watermelon plant at night. They cut the stem at the soil level, causing the plant to die. To manage cutworms, you can use collars made of cardboard or plastic around the base of the plant or apply insecticides or biocontrol agents.
3. Squash Bugs: Squash bugs are flat, gray or brown insects that feed on the leaves of the watermelon plant, causing them to wither and die. They also inject toxins into the plant that can lead to wilting and death. You can manage squash bugs by manually removing them, using insecticides, or by introducing natural predators like tachinid flies and spined soldier bugs.
Effective management of pests and diseases is essential for growing healthy and productive watermelon plants. Regular monitoring of the plants for signs of these pests and diseases is the first step towards their management. A combination of cultural, biological, and chemical control measures can help you manage these problems and ensure a successful watermelon harvest.
