Application methods of several Chemical Control agents for Cotton

The chemical regulators commonly used in cotton production are meth, butene, ethephon, triacontanol, chitin and so on. Some of these chemical regulators can shape ideal plant types and form groups with high light efficiency per unit area; some can promote plant growth and reduce the occurrence of diseases and insect pests; and some can promote ripening and effectively regulate the mature period. so as to reduce the harm of disastrous weather. In short, the scientific use of various chemical control agents in cotton production is beneficial to the improvement of yield and quality.

1. Thalidomide can not only reduce cotton plant height, reduce fruit branch number and cotton boll shedding, increase boll number, but also effectively coordinate the contradiction between ontogeny and population development, improve photosynthetic efficiency and promote high yield. Generally, cotton can be applied 4 times during the growth period, the first time used in the bud stage, every 667 square meters with 0.51 grams of water 20 kg spray, controlled up and down, steady growth and bud growth. The second time in the early flowering stage, spray 1.51 grams of water with 30 kilograms of water every 667 square meters to prevent vigorous growth and bolls. For the third time in the flower and boll stage, 34 grams of water was sprayed at the top of the crown and fruit node with 34 grams of water every 667 square meters to regulate the growth of plant type. The fourth time is that before entering the boll opening period, there is a trend of prosperity and growth can be re-controlled, capping with 34 grams of water for every 667 square meters, in order to control late buds, shorten the upper fruit nodes, and prevent the proliferation of ineffective nodes and superfluous buds.

2. Zhuangzhu can not only avoid, resist and dispel insects, but also control the overgrowth of cotton, make the individual growth compact and robust, enhance the physiological resistance of the plant, and reduce the shedding of buds and bolls. In order to improve the effect of Zhuangzhuangsu spraying, it is necessary to look at the soil and seedlings, but the "three kinds of seedlings" with poor soil, water shortage and poor growth should not be applied. Fertilizer and water conditions are good, the performance of overgrowth can be applied in the full bud stage and early flowering stage every 667 square meters with 25% Zhuangzhuangsu 5 ml to 40 kg of water spray once. In full bloom, 10 ml of 25% zhuangsu is sprayed on 40 kg of water every 667 square meters.

3. Ethephon is mainly used in all kinds of late-maturing cotton fields and cotton fields that need ripening and early stubble. Spraying should be carried out when the temperature is higher than 20 ℃ in order to facilitate the decomposition and release of ethylene. Use time and method: it should be sprayed after the boll period of the upper cotton boll reaches more than 40 days, and the northern cotton area should be sprayed about 20 days before the arrival of the dry frost period. generally, 40% ethephon 300 800 times liquid 60 kg spray is used for every 667 square meters. Pay attention to the use of ethephon to promote ripening, the liquid should be directly attached to the boll body to minimize leaf interception, should not be mixed with alkaline pesticides, and should not be used in cotton fields and seed fields that can open bolls normally and with low productivity.

4. The use of triacontanol before sowing can increase the germination energy and germination rate of seeds, and the use of triacontanol and triacontanol before sowing can reduce the shedding of buds and bolls. The method is as follows: soaking seeds with 0.1 mg / kg triacontanol for 8 hours before sowing, spraying 0.1 mg / kg triacontanol solution at full flowering stage and late flowering stage respectively. When cotton is sprayed with triacontanol, it can also be mixed with pesticides (such as dimethoate) to control wheat aphids. The middle and late growth potential can be mixed with available fertilizers (such as urea, potassium dihydrogen phosphate, etc.).

5. Chitin can be used in the whole growth period of cotton. The application in the early stage can make the root system developed, the stem plant strong, the leaf hypertrophy, relieve the adverse effects of drug injury, fertilizer injury and disastrous weather, enhance the stress resistance of cotton and promote the balanced growth of cotton. It has a remarkable control effect on cotton damping-off, blight, anthracnose, especially on soil-borne diseases such as Fusarium wilt. In the middle and later stage, cotton buds were enlarged, bolls fell less, cotton peach expanded rapidly, and cotton quality was good. The method of use is as follows: mixing seeds with 50 times solution, soaking seeds for 12 hours for 20 hours, then sowing seeds slightly, irrigating roots with 600 times solution at seedling height of 10 cm 20 cm and budding stage, and spraying with 600 times 800 times solution for 2 times in the middle and later stage.