Questions and answers on cotton management technology in the later stage

1. When will the post-management of cotton begin?

Answer: the cotton field management after the end of the flowering and boll period is called cotton late management. The Yellow River basin in China generally begins in early September and the Yangtze River basin in late August.

2. What are the main tasks of cotton management in the later stage?

Answer: boll opening period is the key period to determine the quality of cotton fiber, so first of all, we should give priority to protecting bolls, increasing boll weight and increasing lint percentage; secondly, we should give priority to protecting roots and leaves, promoting precocious maturity and preventing premature senility; third, we should solve the contradiction between high yield and bumper harvest and rotten bolls in overcast and rain, greedy green late maturity and too much ossified cotton.

3. What is the basic appearance of high yield and early maturity without premature senility in the later stage of cotton?

Answer: the red pole and green leaves are well ventilated, the leaf green veins are yellow and not greedy, the peach shell is not shaded, and the peach shell and thin leaves are smooth. The End of Heat saw the double flowers, and the leaves gradually yellowed after White Dew.

After harvesting the flowers, the batch of leaves were dropped at once, and Frosts Descent put out the catkins before and after. Normal cotton fields require half of the peaches to open on National Day and half of the cotton leaves after the middle of October. If after the middle of October, the longer the cotton leaves are, the better they look, then it is easy to form green peaches, green stalks, greedy green late ripening and not high yield.

4. How to master the water and fertilizer management in the later stage of cotton?

The temperature dropped in the later stage of cotton, and the water demand gradually decreased. At this stage, the water demand accounted for 10% of the total water demand, and the field capacity should be maintained at 60%. In case of drought in the early flocculation period, we should adhere to watering, but the amount of water should not be too large, so as to avoid greedy green and late ripening, generally only half of the ditch water is needed. Due to improper management in the early and middle stages, or cotton fields with exuberant growth due to too much water and fertilizer, serious shedding of cotton bolls in the middle and lower parts, or cotton fields with loose autumn peaches, tall, large and empty cotton trees, and green buds in the later stage, the cotton fields should not be fertilized in the later stage. In general, insect-resistant cotton fields with normal management in the early stage are more sensitive to the demand for potash fertilizer, so sufficient potash fertilizer should be applied when topdressing. According to the experience of my association for many years, it is found that when there are symptoms of potassium deficiency in cotton fields, the effect of extra-root topdressing every 5 days is more obvious. Application method: 22 taels of potassium dihydrogen phosphate per mu + half jin of potassium sulfate + 2 taels of urea and 60 jin of water. It is best to spray after 4 p.m. For the cotton fields with many peaches in the middle and lower parts, or lack of fertilizer and premature senescence, liquid fertilizer should be sprayed as soon as possible, and other liquid fertilizers can also be sprayed to supplement the nutrients needed for cotton in time, prevent premature senescence, increase upper peaches, increase boll weight and increase cotton yield.