Ministry of Agriculture: Guidance on cotton production technology in the middle and later period of 2017

In order to ensure the stable production and income increase of cotton this year, according to the climate characteristics and actual situation of different production areas, the National Agricultural Technology Promotion Service Center, together with the cotton expert guidance group of the Ministry of agriculture, studied and formulated the guidance on cotton production technology in the middle and later period of 2017.

——Northwest inland cotton area

The growth of cotton is generally good, so the field management should be strengthened in the later stage to solve the problems of early senescence and late maturity.

1. Fertilizer and water management. In the normal cotton field, drip irrigation was carried out 3-4 times from August to September, and the strength of fertilizer and water was medium. The management of fertilizer and water should be strengthened in the early aging cotton field, and 2-3kg of potassium fertilizer should be added per mu to postpone the water cut-off time; the fertilizer and water should be controlled in the late maturing cotton field.

2. Pest control. It mainly aims at the control of cotton bollworm, autumn aphid and spider in the middle and later period. The cotton fields with serious diseases and insect pests should be treated with medicine in time and controlled by spray.

3. Recovery management. Remove obstacles and sundries (mulch, weeds, drip irrigation belt, etc.) in cotton field before harvesting. Spray defoliant timely when the top cotton boll is basically mature, the rate of Bolling is over 40%, and the temperature is stable at 18 ℃ - 20 ℃. According to the standard, pay attention to prevent the pollution of the opposite fiber.

——Cotton area in the Yellow River Basin

Affected by the high temperature and drought in the early stage, the growth process of cotton was more than 10 days earlier than that of the whole year. In view of the problems of early aging and rotten bolls in cotton field, the management of cotton in the middle and later period should be strengthened.

1. Fertilizer and water operation research. 3% urea solution and 0.5% potassium dihydrogen phosphate solution can be used for the early aging cotton field. Spray once every 5-7 days, 2-3 times in succession. Cotton fields with irrigation conditions shall be watered timely according to the moisture content. As soon as possible, we should strengthen the dredging of ditches to ensure the smoothness of the three ditches, so as to prevent the cotton fields from being damaged by waterlogging.

2. Field management. In the late stage of early aging cotton field, secondary growth is easy to occur, so the new buds should be removed in time. Attention should be paid to the control of cotton bollworm. This year, the occurrence of grey planthopper in cotton field has been widespread. Cotton bollworm should choose pesticides (such as Saidan, etc.) which have little killing effect on natural enemies, and spider can choose special killing agent. The control of Boll disease in cotton field should be carried out by spraying carbendazim, chlorothalonil and thiophanate methyl.

3. Ripening and harvesting. The application of ethephon in Late Maturing Cotton Fields and those that need early stubble should be promoted. Harvest in time, 5-7 days after wadding, implement separate collection, separate sun, separate storage, separate sale, control the mixing of heterosexual fiber into seed cotton. The time of pulling firewood should be postponed in the area of garlic cotton double cropping, and the straw should be returned to the field or pulled firewood as soon as possible after the flowers are collected in other cotton areas.

——Cotton area in the Yangtze River Basin

The growth period of cotton was delayed about 10 days due to the influence of rainy days and high temperature and drought. In view of the problem of late development and late maturity, we should strengthen the management in the middle and later stages.

1. Top dressing and pruning. In the early aging cotton field, 0.03% potassium dihydrogen phosphate should be used for foliar topdressing before the middle of September, and spraying once a week. Remove the invalid branches, middle and lower old leaves and vegetative buds in time, enhance the transparency and ventilation, increase the boll forming rate and boll weight of the upper part, and prevent the boll from rotting.

2. Pest prevention and mitigation. Pay close attention to the occurrence of the four generations of cotton bollworm, pink bollworm, red spider, mirid bug and Bemisia tabaci, and control them according to the situation. Pay close attention to the weather change and prepare the disaster prevention plan in advance.

3. Ripening and harvesting. For cotton fields that can not normally crack and boll, such as live or late sowing and late ripening, ethephon can be sprayed to accelerate ripening. It's better to harvest cotton bolls 5-7 days after normal boll discharge. The links such as harvesting, drying and packaging should adhere to the principle of separate collection, separate drying, separate storage and separate sale. Attention should be paid to prevent the mixing of heterosexual fibers to ensure the quality of cotton.