A Complete Guide to Management Key Points During the Cotton Yield Formation Period

This year, the light and heat conditions in the early stage were relatively favorable for cotton growth, but the recent low temperature, scant sunlight, and rainy weather have been extremely unfavorable to cotton growth, and boll shedding has increased noticeably. We are currently in the critical period for cotton yield formation. To secure a high cotton yield, the following management measures should be strengthened:

1. Supplemental application of top-covering fertilizer and foliar spraying. For cotton fields with many set bolls and fields showing premature senescence, apply 5-7.5 kg of urea per 667 sq m, or combine this with pest control for foliar spraying.

2. Reasonable pruning and chemical regulation. Due to the recent excessive rain, cotton fields have suffered from poor ventilation and light penetration, so plants should be pushed together into ridges. At the same time, for overly vigorous cotton fields, use 2-3 g of 98% mepiquat chloride per 667 sq m; for cotton fields with steady growth, use 1-2 g of 98% mepiquat chloride per 667 sq m; for cotton fields with poorer growth, use 0.5-1.0 g of 98% mepiquat chloride per 667 sq m. It is best to do this after fertilizing and before irrigation.

3. Integrated pest and disease control. Strengthen control of cotton bollworm, mirids, whiteflies, and others. Pyrethroid and organophosphorus pesticides can be used in rotation, and care should be taken to protect natural enemies; generally apply after 5 p.m. For Verticillium wilt and Fusarium wilt, prevention should be the main approach. In the early stage of disease onset, a 500-fold 25% Shibaike solution can be used for root drenching, applying 50-100 mL per diseased plant. For severely affected fields, drench again after an interval of 5-7 days. At the same time, use a 0.2% potassium dihydrogen phosphate solution plus 1% urea solution for foliar spraying every 5-7 days, for 2-3 consecutive sprays.