Description of Phaseolus aureus Roxb.
Phaseolus aureus Roxb., commonly known as the mung bean, is a small-seeded leguminous plant that is native to India, but has been introduced and naturalized in most tropical and subtropical regions around the world. It belongs to the family Fabaceae and is widely cultivated for its edible seeds.
General Appearance
The mung bean is an annual plant that typically grows up to 30-120 cm tall. It has a slender stem that is light green in color and is covered with fine hairs. The leaves are trifoliate, with each leaflet being oval or lance-shaped, measuring 5-15 cm long and 2-8 cm wide. The flowers are small, pea-like, and usually yellow or light green in color. The fruit is a thin, cylindrical, and hairy pod that contains 10-15 seeds.
Common Names
Aside from mung bean, Phaseolus aureus Roxb. is known by different names depending on the location. In India, it is called 'moong dal' or simply 'moong', while in China, it is referred to as ‘lü dou’. Other common names include green gram, golden gram, and mash bean.
Uses
The mung bean is a highly nutritious food source that is popular in many cuisines around the world. The seeds are rich in protein, fiber, and a wide range of vitamins and minerals. They can be eaten whole or split, and can be cooked in a variety of ways such as boiling, sprouting, and stir-frying. Mung bean sprouts are a common ingredient in many Asian dishes and are widely used in salads, sandwiches, and soups. The leaves and pods of the plant are also used as animal feed. Aside from its culinary uses, the mung bean has also been traditionally used in Ayurvedic medicine as a remedy for various illnesses such as digestive disorders, fever, and inflammation.
Light Requirements:
Phaseolus aureus Roxb. requires full sun exposure for optimal growth and yield. The plant needs at least 6-8 hours of direct sunlight daily. Limited sunlight exposure can lead to stunted and weak plants with reduced yields.
Temperature Requirements:
The plant can grow well in tropical and subtropical climates with temperatures ranging from 25 to 35 degrees Celsius. The minimum temperature requirement for growth is 16 degrees Celsius. Lower temperatures may hamper seed germination, while higher temperatures can stress the plant and reduce yield.
Soil Requirements:
The plant prefers well-drained, loamy soil with a pH range of 5.0 to 6.5. It can tolerate moderately acidic soil but does not grow well in alkaline soils. The ideal soil temperature for seed germination is between 20 to 25 degrees Celsius. The plant requires adequate soil moisture for growth; however, waterlogged soil can stunt its growth and reduce yield.
Cultivation of Phaseolus aureus Roxb.
Phaseolus aureus Roxb., also known as mung bean, is an important legume crop grown for its edible seeds. The following are some cultivation methods for this plant:
- Choose a well-draining soil with a pH level of 6 to 7.5 for optimal growth.
- Plant the seeds during the warm season, as mung beans require a minimum temperature of 15°C for germination.
- Ensure the seeds are sowed at a depth of 1-2 inches, with a spacing between 6-8 inches apart between rows and 2-4 inches between seeds.
- Mulch around the plants with straw or grass clippings to keep the soil moist and cool.
- Weed regularly, as mung beans are susceptible to competition from weeds.
Watering Needs
Mung beans require regular watering during their growing season to ensure healthy growth and good seed production. Here are some tips for watering:
- Water the plants deeply and infrequently to promote deep root growth and a healthy plant structure.
- Ensure the soil is evenly moist but not waterlogged, as mung beans do not tolerate waterlogging and it can lead to root rot.
- Give the plants 1 to 2 inches of water per week, depending on weather conditions.
- Do not let the soil dry out completely, as this can cause the plants to wilt and reduce their yield.
Fertilization
Applying the right fertilizers at the right time is essential for getting the best yield from your mung bean plants. Here are some fertilizer tips:
- Before planting, incorporate well-rotted manure or compost into the soil to enrich it with organic matter.
- Apply a balanced fertilizer such as 10-10-10 during the early stages of growth.
- Increase the nitrogen content in the soil by side-dressing the plants with a nitrogen-rich fertilizer such as urea, at the beginning of flowering.
- Do not over-fertilize, as this can lead to excessive vegetative growth and poor pod development.
Pruning
Pruning helps to control the growth of the mung bean plant and encourages the development of pods. Here are some tips on pruning:
- Pinch off the growing tip of the main stem after the plant has reached a height of 6 inches to encourage branching and more flowers.
- Remove any yellow or diseased leaves to prevent the spread of disease.
- Pinch off any developing flowers before they turn into pods to direct the plant's energy towards existing pods.
- Harvest the pods as they mature to encourage new growth and prolong the plant's production period.
Propagation of Phaseolus aureus Roxb.
Phaseolus aureus Roxb., commonly known as mung bean or green gram, is a hardy plant that can be propagated through various methods such as:
Seed Propagation
Seed propagation is the most common method of propagating mung beans. The seeds should be planted in a well-drained soil mix with a pH range of 6.0-7.0. The seeds should be sown in rows about 15-20cm apart, and the depth of the seeds should be around 2-3cm. Water the soil immediately after planting and water the seedlings regularly to ensure that the soil remains damp but not waterlogged. Seedlings usually emerge within a week or so of planting.
Cuttings Propagation
Mung beans can also be propagated through cuttings, though this is less common than seed propagation. To propagate mung beans through cuttings, take cuttings from healthy plants with a sharp, sterile knife. Cuttings should be around 10-15cm long, with a few leaves attached to the stem. Dip the cuttings in rooting hormone and plant them in a well-drained soil mix, keeping the soil around the cuttings damp but not waterlogged. Cuttings should root in about 2-3 weeks.
Tissue Culture Propagation
Tissue culture propagation of mung beans is a more advanced method and is typically done in a laboratory setting. This method involves taking small pieces of plant tissue, called explants, and placing them in a nutrient-rich medium. The explants then grow into new plants, which can be transferred to soil once they're big enough.
Disease Management
Phaseolus aureus Roxb. is susceptible to various fungal, bacterial, and viral diseases that can cause significant yield losses. The most common diseases that affect this plant are:
- Anthracnose: This fungal disease causes leaf spots, defoliation, and pod rot. To manage anthracnose, plant resistant varieties, practice crop rotation, and apply fungicides.
- Rust: Rust is a fungal disease that causes powdery orange or reddish-brown pustules on leaves and stem. To manage rust, plant resistant varieties, remove infected plant debris, and apply fungicides.
- Bacterial blight: This bacterial disease causes water-soaked lesions on leaves, stems, and pods. To manage bacterial blight, plant resistant varieties, practice crop rotation, and apply copper-based bactericides.
- Mosaic viruses: Several viruses can infect Phaseolus aureus Roxb. and cause mosaic patterns on the leaves, stunted growth, and reduced yield. To manage mosaic viruses, plant disease-free seeds, remove infected plants, and control the insect vectors.
It is essential to monitor the plants regularly to detect any disease symptoms and take prompt actions to prevent the spread of the disease.
Pest Management
Phaseolus aureus Roxb. is susceptible to various insect pests that can cause significant economic losses. Some of the common pests that affect this plant are:
- Aphids: Aphids are small, soft-bodied insects that feed on the sap of the plant, causing stunted growth and yellowing of leaves. To manage aphids, use insecticidal soaps or oils and plant companion crops that attract natural enemies.
- Bean beetle: Bean beetles are small yellowish-green beetles that feed on the leaves and pods of the plant. To manage bean beetles, handpick and destroy the beetles and apply organic insecticides.
- Cutworms: Cutworms are caterpillars that cut the seedlings at the soil level. To manage cutworms, avoid planting in weedy fields, use collars around the plants, and apply Bacillus thuringiensis-based insecticides.
- Spider mites: Spider mites are tiny arachnids that suck the sap from the leaves and cause yellowing and bronzing of leaves. To manage spider mites, use insecticidal soaps or oils and maintain high humidity around the plants.
It is crucial to monitor the plants regularly for insect pest infestations and take prompt actions to prevent the spread of the infestation. Crop rotation, intercropping, and use of resistant varieties can also help manage insect pests effectively.
