Management of cotton field after rapid change of drought and flood

At present, it is the cotton vegetative growth into the peak, and gradually turn to the stage of reproductive growth, but also to absorb more fertilizer and water and is very sensitive period. Since June 4, there have been many rainy days, the air humidity is very high, and the temperature hovers at 25: 30 ℃. Fusarium wilt has been induced in many old cotton fields that have been planted for many years. The general wilt disease rate is about 5%, the serious field disease rate is about 10%, and the incidence rate in some areas is about 20%. Some cotton field bugs, cotton bollworms, red spiders and aphids are also doing harm.

At the same time, for the cotton with partial application of nitrogen fertilizer, under the abundant environmental conditions of Rain Water, the extreme reversal of fertilizer and water can easily lead to crazy growth, and the average daily growth of the main stem is often more than 3 cm overnight. In this way, cotton will be closed prematurely, the cotton field will be shaded seriously, and a large number of buds and bolls will fall off. In some waterlogged cotton fields, cotton suffers from waterlogging after drought, and the ecological environment is even worse. Therefore, the local cotton areas should adopt measures according to the local seedling system, strengthen the management of cotton bud stage and flower and boll stage, and strive to resist disasters and achieve a bumper harvest.

First, promote the combination of control and balance growth. For cotton seedlings that have not entered the bud stage, the application of available fertilizer should be given priority to to speed up the growth of cotton seedlings. For cotton seedlings entering the bud stage and flower and boll stage, we should mainly apply high-content compound fertilizer and slow-release fertilizer, 15-25 kg per mu, 15 kg potash fertilizer, swing moisture in ditches or burrowing, and avoid spreading in the field. At this time, fertilization is aimed at building a high-yield shelf of cotton as early as possible, so that cotton can be closed in late July. For flourishing or crazy-growing cotton, it is necessary to choose zhuangzhuangsu or medroxyamine spray as soon as possible, in the early stage, 4 milliliters per mu or 1 gram of megalomide, and then gradually increased to 8 milliliters or 2 grams of 3 grams. Last year, some farmers blindly increased their consumption and excessive chemical control, so that the peach rate of cotton decreased sharply, and lessons must be learned.

Second, prevent diseases and insects and grow safely. For the cotton fields with Fusarium wilt, rotten organic fertilizer, bio-organic compound fertilizer and potash fertilizer should be applied to enhance the ability of defense and recovery against Fusarium wilt, and some pesticides to alleviate Fusarium wilt, such as Fusarium wilt, should be applied. For the pests that have been seen, we should give priority to the prevention of blind bugs and control other pests. You can choose to kill (speed) bug bugs 20: 30 milliliters per mu, or 5000 times of 2% methylaminoavermectin benzoate wettable liquid, or acetamiprid 3% EC 1500-2000 times, or imidacloprid wettable powder 1500 times.

Third, dredge the "four ditches" and let the rain stay in the fields. The surrounding ditches, chamber ditches, waist ditches and surrounding drainage ditches in the cotton field should be cleaned thoroughly so that the stains can be drained and drought can be resisted. At the same time, it is necessary to break the board and loosen the soil after the rain, cultivate the soil to build ridges and prevent lodging.