How to cultivate cotton during the squaring stage? A detailed explanation of the key technical points

In 2008, the climate during the cotton squaring stage was extremely unfavorable for cotton growth, with low temperatures and high humidity, causing cotton growth to lag 3-5 days behind the same period in previous years, with severe cotton diseases and generally weak growth. How to strengthen management during the squaring stage and build a good framework for high yield? The following points should be noted in management:

Apply squaring fertilizer steadily: Apply fertilizer scientifically according to soil fertility conditions, base fertilizer application, and cotton growth. Focus on phosphorus and potassium fertilizers. For cotton fields with high soil fertility, sufficient base fertilizer, and vigorous growth, it is not suitable to apply nitrogen fertilizer as a top dressing; instead, 25-40 kg of cake fertilizer per mu may be appropriately applied. For fields with ordinary soil fertility and normal growth, apply 15-20 kg of compound fertilizer per mu as a top dressing. Especially for cotton fields with poor growth and insufficient soil fertility this year, nitrogen fertilizer may be appropriately applied as a top dressing to promote strong plants and early development. When applying fertilizer, it should be applied deeply and pressed down.

Implement scientific chemical regulation: In cotton fields in areas with excessive rainfall, attention should be paid to chemical regulation. In principle, observe the sky, the soil, and the cotton, and base it on the daily growth increment of the main stem. When the daily growth increment of the main stem exceeds 1 cm at the early squaring stage and exceeds 2 cm at the full squaring stage, use the method of small amounts applied multiple times, controlling waterlogging but not drought, and controlling excessive vigor but not healthy growth. At the early squaring stage, generally use 2-3 ml of 25% mepiquat chloride per mu each time; at the full squaring stage, use 4-6 ml, mixed with 15-30 kg of water for overhead spraying.

Prune cotton in time and retain leaf branches skillfully: After cotton squaring and the obvious extension of fruiting branches, promptly remove the leaf branches below the first fruiting branch, removing only the branches and not the leaves, to reduce unnecessary consumption of cotton nutrients. In areas of missing plants and broken rows caused by severely diseased plots this year, leaf branches should be skillfully retained. On both sides of the missing plant area, 1-2 robust leaf branches may be selected and retained to fill the gap with branches and make full use of space. When selecting and retaining leaf branches, attention should be paid to retaining the upper leaf branches as much as possible.

Focus on disease control: The squaring stage is the period when Fusarium wilt occurs heavily. Timely intertillage and loosening of the soil to dissipate moisture are important, and the quality of intertillage is most critical. Deep intertillage promotes root penetration, increases temperature and dissipates moisture to improve cotton growth, and destroys the conditions for pathogen reproduction and spread. Do a good job in chemical control, focusing on prevention and combining prevention with control. Spray fungicides plus foliar fertilizer promptly before or after rain to achieve the goals of preventing and treating diseases and strengthening plants, and promote cotton growth.

Do a good job in removing plastic film and hilling soil: After removing the film, it is beneficial for dissipating moisture, improving root penetration, and strengthening the ability to absorb water and nutrients. The time should mainly be late June, and operation is strictly prohibited after entering the full flowering stage. At the same time, combine with watering on rainy days or after film removal, and combine with hilling soil to effectively prevent cotton lodging.

The above management measures are key to achieving high cotton yields. It is hoped that the majority of cotton farmers will carry them out according to their own conditions and lay a solid foundation for high cotton yields this year.