Plum rain season has arrived, cotton needs early prevention and control of the "three harms"

Currently, cotton seedlings have entered the squaring stage, and at the same time have stepped into the annual plum rain season. According to meteorological data, from May 30 to 31, in some major cotton-producing counties, cities and districts of Wuhan, Xiaogan, Suizhou, Ezhou and other cities, rainfall reached over 100 mm, causing some cotton fields to be flooded by heavy rain, and in some low-lying sections of cotton fields the cotton seedlings were completely submerged. While cotton seedlings suffer from waterlogging damage, diseases and weed damage also follow one after another. The "three harms" of cotton have struck cotton farmers simultaneously. According to surveys, some cotton fields now have more than 100 weeds per sq m, with weeds taller than the cotton seedlings, and weeds competing with cotton for fertilizer, light and living space. Although it is gradually clearing after the rain, the air humidity is very high and the temperature has dropped, which is suitable for the occurrence and damage of Fusarium wilt. In some old cotton fields with residual Fusarium wilt bacteria and some cotton fields with non-resistant varieties, Fusarium wilt has already appeared, and in severe cases cotton seedling death has occurred, causing gaps and broken rows. If the "three harms" are allowed to spread, cotton yield and income will inevitably be reduced. Facing the "three harms" that have already occurred in cotton fields, the vast number of cotton farmers must prevent and control them early, and for the potential "three harms", they must also take preventive measures early. The specific measures are as follows: First, drain the waterlogged fields promptly and straighten and wash the seedlings. The heavy rain exposed the fact that the water systems of some of our cotton fields are not adequately matched, especially some newly added cotton fields, whose water systems are even less matched. The water system facilities of some old cotton fields have also aged. Fortunately, due to the severe drought in the previous period, local reservoirs do not hold much water, which is conducive to pumping and draining the waterlogged fields. Therefore, leaders in cotton areas at all levels should promptly organize farmers to drain the waterlogged fields and improve water system facilities. At the same time, organize farmers to quickly straighten and wash the submerged cotton seedlings. According to experience over the years, as long as the water is drained promptly, the cotton seedlings are straightened and washed clean with water sprayed from a sprayer, and fertilizer is applied to promote seedling growth when soil moisture is suitable, the cotton seedlings can quickly recover normal growth. Second, apply both fertilizer and pesticide, and prevent disease early. Applying squaring fertilizer can, first, supplement cotton nutrition and enhance cotton's stress resistance; second, applying organic fertilizer can improve resistance to Fusarium wilt. In particular, applying organic compound fertilizer has a very good function of inhibiting pathogens, improving soil and building soil fertility. At the same time, applying general K, fulvic acid and similar pesticides can also prevent and control Fusarium wilt, and can reduce or alleviate the harm. Third, cultivate and hoe frequently, so that the soil is loose and the weeds are clean. The cotton squaring stage is also a favorable period for intertillage to break up soil compaction. For cotton fields with insufficient base fertilizer, various fertilizers should also be applied deeply by breaking the hardpan during deep intertillage. For farmers planting insect-resistant cotton, special emphasis should be placed on applying potassium fertilizer, with no less than 15 kg of potassium applied per mu. Deep intertillage also requires frequent intertillage and frequent weeding, so that the soil is loose and the weeds are clean, with the top layer loose and the lower layer firm. For some large cotton-growing households, or households short of labor, herbicides such as glyphosate can be sprayed in the wide rows of cotton, but special attention must be paid to fitting the spray head with a plastic safety cover to prevent killing the weeds while also injuring the cotton seedlings.