Amaranthus is leafy vegetable grown commonly in Terai region of Nepal. High yield per unit of area & high nutritional value are beautiful characteristics of this crop. Amaranthus blitum & Amaranthus tricolor are most common species commonly grown in Nepal & world.
This crop is very popular due to high vitamin A content along with vitamin C, protein & minerals too. Young & tender leaves are eaten as cooked vegetables.
Amaranthus is originated from India. (Thompson & Kelly, 1957)
The commonly available & recommended varieties are:
- Coimbotire-1 (Co-1) – Amaranthus dubium: This variety was released from Tmil Nadu University, India. It is usually grown for its green leaves as well as mature stem. Seeds are small and black, tolerates pests & diseases.
- Coimbotire-2 (Co-2) – Amaranthus tricolor (Badi chauli): Stem is thick green, large leaves, green colored and suitable for summer crops. It responds well to cuttings.
- Coimbotire-3 (Co-3)
- Coimbotire-5 (Co-5)
- Pusa kiran
- Pusa Kirti
- Pusa lal
Amaranthus are influenced much by day length & responds differently to the change in photo & thermo-periodism. It is warm season crop and can be cultivated from Terai to Mid-Hills with adjustment of planting time. It is susceptible to frost and requires hot & humid climate.
Soil & field preparation:
It can be grown in wide range of soils but sandy loam soil with slightly acidic pH is better for growth & development. Well drained, fertile & rich in organic matter sort of soil is best suited for this crop. The soil pH should be 5.5-7.5 for better crop & for this 3-4 ploughing followed by planking is necessary for good tilth.
Manuring & fertilizer:
Incorporate 20 tons of well decomposed FYM or compost during field preparation. Inorganic fertilizers of 50: 30: 20 kg NPK/ha is recommended where P & K are applied as basal dose where N is applied in 3 split doses. Initially at 20 days after sowing, 2nd & 3rd after second & third cuttings.
Amaranthus can be grown in different season according to geographical locations.
- Direct sowing of seed in the field in the rows or broadcasting.
- Raising of seedlings and then transplanting in the main field.
- Since seeds are very small, these should be sown very carefully.
2-2.5 kg/ha is sufficient for direct sowing method & 1-1.5 kg/ha for transplanting.
Recommended spacing is 20 cm * 15 cm (row to row * plant to plant) is maintained in the field for easy intercultural operations. Sowing should be 1 cm deep with adequate moisture.
Irrigation & Inter-cultural operations:
Light irrigation followed by sowing of seed for germination of seed. It requires adequate water for growth & higher yield during summer irrigation is given at 3-5 days interval. 2-3 weeding are essential.
Harvesting & yield:
Clipping starts from 25-30 days of seed sowing & continues until 60 days at an interval of 7-10 days.
Yield depends upon the type of cultivar, management practices, followed and growing seasons. Yield vary from 20-30 tons/ha.
Since it is leafy vegetables, its storage is a problem and it cannot be stored for long time under ordinary condition. But they can be stored for 10-14 days at 0 degree Celsius with 90-95% RH. Well dried leaves of Amaranthus can be stored for 1 year. Pre-harvest spray of Benzoic acid at 5-10 ppm helps Amaranthus to retain fresh green color for an additional 3-5 days.
Amaranthus is cross-pollinated crop, which requires isolation distance of about 400 m between two cultivars. It is quick growing crops & forms seed in about 10-12 weeks. After taking a number of leaf cuttings, only a few last cuttings can be omitted to produce seeds. After harvesting, initial drying of spikes can be done in sun and drying the seeds to a 15% moisture content are usually practiced so that the seeds can be threshed with pliable bamboo sticks. Seed yield is about 200 kg/ha.
Mosaic of broad leaf mustard:
- Use disease free seeds for planting.
- Use insecticide for controlling aphids.
Alternaria leaf spot of broad leaf mustard & spinach:
- Long crop rotation
- Spraying of crop with fungicides (Dithane Z-78 0.25% or Blitox-50 @ 0.3%) is recommended.
Leaf spot disease:
- Spray Blitox @ 0.2% or Bordeaux mixture @ 1% at 15 days interval.
- Follow crop rotation.
- Remove crop debris of previous crops.
- Adopt proper crop rotation.
- Spraying of crop with fungicides (Dithane Z-78 0.25% or Blitox-50 @ 0.3%) is recommended for asparagus.
- Leaf eating caterpillar : they are the major insect pest affecting asparagus plant.
Source Book: Vegetable production technology