Key points of open field cultivation techniques for high quality and high yield of cowpea

Cowpea likes warmth and has strong tolerance to drought, but not to waterlogging. The cowpea planting mode of plastic film mulching on the ridge is usually adopted, the yield per mu can reach 3148 kg, the average output value per mu is 3148 yuan, according to the average physicochemical input cost of 1800.8 yuan per mu, the average income per mu is 1347 yuan.

1 Variety selection

Excellent varieties with exuberant stem growth, strong heat tolerance, early maturity, high yield and strong adaptability were selected. The purity of the seed is not less than 95%, the germination rate is not less than 90%, and after careful selection, the seed should be dried before sowing, and if necessary, the seed can be mixed with 50%, and the dosage is 0.2% of the amount of seed used.

1.1 sowing

It is generally divided into two ways: direct seeding and seedling transplanting. The sowing time in the small arch shed is late March, the transplanting time in open field is late March, and the open field direct seeding time is mid-April. The local temperature reaches 12: 14 ℃, which can be broadcast live on a continuous sunny day. Before sowing, make a small high border with a depth of 25 inches, a width of 40 inches and a width of 70cm, then spread plastic film and sow two rows of cowpeas on both sides of the ditch wall. Plant distance 22cm, sowing depth 3~4cm, 3-4 seeds per hole, seed amount 2.5~3kg per mu, diammonium carbonate as seed fertilizer.

2. Land preparation

In late March, depending on soil moisture irrigation, 2 tons of high-quality mature farm manure and calcium superphosphate 20~30kg were applied per mu. The ploughing depth is 20 times, and the quality of soil preparation is flat and without stubble, which is to be sown.

3. Field management

In case of heavy rain after the current direct seeding, release the seedlings in time to seal the air and break the hardening. When transplanting seedlings, it is common to open holes before the fourth pair of true leaves, pour live water after planting, and fill the planting holes.

Cowpea is a crop that likes fertilizer and water, so less nitrogen fertilizer should be applied in the early stage, and podding fertilizer should be applied again in the flowering and podding stage. Irrigation adopts the principle of a small number of times to prevent rotting roots, falling leaves, falling flowers and so on. Cowpea seedlings and trailing period are generally topdressing urea 1 times twice, each time 5kg/ mu. At the early flowering stage, urea 5~10kg/ mu and potassium dihydrogen phosphate 2kg/ mu were applied. During the harvest period, urea 1~2kg/ mu was applied every 4-5 days.

3.1 pruning

The lateral branches below the first inflorescence were removed when they reached 3 years old to ensure that the main stem was stout, and the lateral branches above the first inflorescence were left with 1 leaf and 2 leaves. When the main vine reaches the top of the shed, pick the heart to control the growth and promote the lower side branches to form flower buds.

3.2 harvesting

Cowpea is a raceme, each inflorescence has 2-5 pairs of flowers, usually only one pair of pods, adequate fertilizer and water, good management, strong plant growth, all flowers can bear pods. After the first pair of pods were harvested, the second pair of flower buds set fruit or developed. The pods are full at 10-12 days after flowering, and can be picked manually when the seeds are not visible. At the initial stage of picking, the pods can be picked every 4-5 days.

(4) Disease and pest control

The main diseases of cowpea are rust, leaf spot and root rot.

Rust and leaf spot: in the early stage of the disease, remove the diseased leaves in time to reduce the spread of the disease, and spray as soon as possible. The main medicament has 50% carbendazim 500 times liquid, or spray control with 75% chlorothalonil 600 times liquid, spray to the leaf surface and back all wet, spray once every 7-10 days, spray 2 times 3 times continuously. It can also be used to control rust and methyl topiramate to control leaf spot.

Root rot: control root rot with carbendazim, dimethazone and germicidal king.

Cowpea pod borer: after entering the flowering stage, when the petals open at 7: 9 a.m., aim at the flowers, spray 1000 times of 50% fenitrothion in time, spray once every 5 days or so, and pick up the fallen flowers in the field at the same time. You can also spray the plant after 5 o'clock in the evening.

Aphids: acetamiprid can be sprayed for spray control, spray to the leaf surface and back all wet, spray about 7 days, spray 2-3 times in a row.

Underground pests: spray with 1000 times of phoxim and sulfur to control underground pests such as ground tigers.