How can cotton be grown well? Key points of planting management techniques

To grow cotton well, you should master the following key techniques.

I. Strictly control the quality of sowing

1. Choose high-quality, high-yield varieties. Choose improved varieties promoted by the local agricultural technology department.

2. Sun the seeds before sowing. Choose a sunny day, spread the seeds on non-cement ground, and sun them for 4-5 days to promote after-ripening of the seeds and increase the germination rate.

3. Sow at the right time. Generally, sowing begins when the soil temperature at 5 cm steadily passes 16 degrees C. The suitable sowing period for film-mulched cotton is April 20-30, and for open-field cotton it is after April 25.

4. Choose a suitable sowing method. Generally, sandy soil should be sown first and then covered with film to prevent surface crusting from pressing the seedlings; clay soil and saline-alkali soil should be covered with film first and then sown, which helps raise soil temperature and prevent salt return. After emergence, the seedlings should be released in time to prevent burning damage to the seedlings.

5. Increase the sowing rate. For manual hole sowing, use 1.5 kg of seed per mu, sowing 3-4 seeds per hole, placed together; for machine sowing, use 2-2.5 kg of seed per mu.

II. Strengthen scientific management

1. Determine the suitable density. Choose different planting densities according to different varieties, different soil fertility, and different cultivation methods. For example, for the nationally approved variety Ji 668, generally 2500-2800 plants per mu on ordinary soil; on poor soil and dry land, more than 3500 plants per mu; for simplified cultivation plots, about 2000 plants per mu. For the variety Jiza 3268, 2000-2200 plants per mu under conventional cultivation; about 1800 plants per mu under simplified cultivation. For the variety Jiza 566, 1800 plants per mu under conventional cultivation; about 1500 plants per mu under simplified cultivation. For DP99B, more than 3500 plants per mu.

2. Top pruning at the right time. For plots using conventional cultivation, top pruning on July 15-20; for plots using simplified cultivation, top pruning on July 10-15. For DP99B, attention should also be paid to removing the side tips in early to mid-August.

3. Remove the film in time. To prevent premature aging in the later stage, the film should be removed in time, with the timing controlled in late June.

III. Promote applicable techniques

(1) Balanced fertilization technique To improve the comprehensive stress resistance of cotton, the balanced fertilization technique should be vigorously promoted. According to the principle of "adequate nitrogen, increased phosphorus, emphasis on potassium, supplementing microelements", adjust the ratio of nitrogen, phosphorus, and potassium to 1:0.5-0.6:1. At the same time, supplement trace fertilizers such as boron and zinc to increase the boll-setting rate.

1. Apply heavy base fertilizer. Apply all phosphorus and potassium fertilizer and 50%-60% of the nitrogen fertilizer as base fertilizer, applying 10 kg of urea, 15-20 kg of diammonium phosphate, 15-20 kg of potassium sulfate, 1 kg of boron fertilizer, and 2 cubic meters of decomposed organic fertilizer per mu.

2. Apply flower and boll fertilizer as topdressing. In early to mid-July, apply 10-15 kg of urea per mu as topdressing. For plots with little base fertilizer and poor growth, an additional 15 kg of diammonium phosphate can be applied. After topdressing, water promptly; where there is no water source, apply fertilizer during rain.

3. Foliar spraying. In the middle and late stages, use 0.5-1.0 kg of urea, 0.2 kg of potassium dihydrogen phosphate, or 15 ml of Fuwanjia per mu, add a small amount of boric acid, and dilute with 50 kg of water for spraying. Spray once every 7-10 days, for a total of 2-3 sprays.

(2) Systematic chemical regulation technique

Systematic chemical regulation is beneficial to root growth and increases stress resistance; it helps control excessive vegetative growth, coordinate the relationship between vegetative and reproductive growth, and reduce shedding of buds and bolls. Therefore, the systematic chemical regulation technique for cotton should be promoted, with special attention to chemical control at the bud stage. Generally, follow the principle of "small amounts and multiple applications, light first and heavy later, gradually increasing the amount", and spray mepiquat chloride 3-4 times during the whole growth period: the 1st time in mid-June, using 1.5 g per mu; the 2nd time in early July, using 2.0 g per mu; the 3rd time at the end of July, using

I. Strictly control the quality of sowing

IV. Do a good job in controlling diseases, insects, and weeds

1. Insect pests. Focus on controlling aphids and thrips at the seedling stage and cotton bollworm and mirids in the middle and late stages. For aphids and thrips, imidacloprid can be selected for control; for cotton bollworm and mirids, a 1:1 mixture of chlorpyrifos and Saibokai can be selected, diluted 1500-2000 times for spraying.

2. Diseases. For damping-off and anthracnose at the seedling stage, control can be carried out by adjusting the sowing date, avoiding low temperatures, seed or soil treatment, and spraying Bordeaux mixture or carbendazim; for verticillium wilt and fusarium wilt, use crop rotation sowing, increase potassium fertilizer application, and pull out diseased plants for control; for red-leaf yellow-wilt disease, solve it by increasing potassium fertilizer application.

3. Weeds. Use 70-90 ml of 48% trifluralin emulsifiable concentrate per mu diluted with 50 kg of water, spray on the ground before sowing, and shallowly harrow 3-5 cm to mix into the soil. Acetochlor or Dual can also be used for weed control.