This year’s cotton field

The period from the beginning of the voicing to the end of the vomiting of cotton, known as the late cotton growth period, is an important period for determining cotton yield and quality. This year, the Huanghuai cotton area is affected by bad weather, and the proportion of Futao and Qiutao is relatively large. Therefore, the later management of cotton fields is particularly important. Specifically, the following aspects should be done:

Drought-proof and flood-proof cotton vegetative growth slowed down in the late growth stage, the stress resistance became worse, and it was very sensitive to drought and flood. The drought and flood had a great impact on yield and quality. Timely watering, drought resistance, drainage and flood control are the key measures to prevent premature aging of cotton, multi-grow early peach, increase boll weight and improve fiber quality. In the northern part of China, most of the years are dry and rainy from September to October. According to the agricultural department's investigation of the autumn drought year: from late August to late September, the water is poured once, and the number of plants per plant is 1.2~1.8, and the single boll is heavy. Increasing 0.13~0.24g, fiber length increasing by 1.2~1.7mm, increasing yield by 15.3%~19.7%; pouring twice water, 1.9~2.87 single boll, single boll weight increasing by 0.15~0.25g, fiber length increasing by 1.9 ~2.4 mm, an increase of 20.3% to 27.7%. When the water content of the 20~40 cm soil layer in the cotton field is lower than 60% of the maximum water holding capacity in the field, it should be watered immediately, but avoid flooding with large water to prevent the rain after the pouring, causing the bud to fall off and the bell Big happens. In case of heavy rain, the fallen cotton plant should be taken care of in time to drain the water in the field within 24 hours.

Spraying topping fertilizer With the popularization of insect-resistant cotton, the premature aging of cotton plants is increasing. The key to preventing premature aging is to apply more topping fertilizer in addition to drought prevention and drainage work. In the late growth stage of cotton, the root absorption capacity is reduced, the soil topdressing is easy to damage the roots, and the fertilizer efficiency is slow, while the root top dressing is adopted, the fertilizer is saved, the fertilizer efficiency is fast, and the yield increase is remarkable. According to the test, from the end of August, spray 0.3% potassium dihydrogen phosphate solution or 1% urea and 2% calcium superphosphate mixture every 7 days, spraying 45~60 kg per mu. Even spraying 2~3 times, the number of peaches per plant can be 1.2~2.1, increasing the yield by 4.6%~6.9%. Spraying the topping fertilizer should be carried out on a cloudy day and evening without strong winds. When spraying fertilizer, it should be aligned with the back of the middle and upper leaves. In order to reduce the loss of fertilizer solution, 100 grams of neutral detergent powder can be added to 50 kg of fertilizer solution, which can be fully dissolved and mixed, and can not only improve the fertilizer efficiency, but also treat pests such as aphids and cotton aphid.

Timely prevention and control of pests and diseases With the weakening of resistance to pests and diseases in the late growth stage of insect-resistant cotton, combined with the increase in the proportion of late-maturing cotton fields this year, and the uneven weather of droughts and floods from July to August, the environment in the late cotton field is extremely beneficial to the occurrence of pests and diseases. Prevention and treatment. When the fourth generation of cotton bollworm has 6 to 10 young larvae, it can be controlled with 4.5% beta-cypermethrin 2000 times solution or 2.5% cyhalothrin 1500 times solution. Red spider damage, when the rate of yellow spotted leaves in the leaves reaches 10%, it can be controlled by 1.8% avermectin 1500 times solution or 20% chlorpyrifos 2000 times solution, and can treat the blind mites. Cotton whitefly on the upper, middle and lower 3 leaves of the cotton plant, the average number of nymphs is 10-15, 20% imidacloprid 1500 times solution, or 48% lesperine 1500 times solution, or 25% chlorpyrifos 1000 times Liquid, or 1.8% avermectin 1500 times solution control. Using the tendency of cotton aphid, the yellow plate is good for hanging. It is necessary to pay attention to the prevention and control of rotten bells, pick up the spots and diseased bells in time, and bring them to the field to strip the sun, which can reduce losses and prevent the spread of diseases.

Correct use of ripening measures should be carried out in a timely manner on the closed cotton fields where the growth is prosperous, such as buds, cut branches, and old leaves, and bring them to the field for centralized treatment. This can reduce the unnecessary consumption of nutrients and water, concentrate nutrients to increase early autumn peaches, improve ventilation and light transmission conditions in cotton fields, promote cotton maturity, increase yield and quality, and reduce pests and diseases. For cotton fields with normal fertility, pruning should be simplified to prevent premature aging caused by excessive pruning. For the cotton fields that are late in maturity, using ethephon ripening, the cotton bolls can be vomited 7 to 10 days earlier, the flowering rate before frost is increased by 9.5%~16.8%, the yield is increased by 6.4%~10.2%, and the income per mu is increased by 40~80 yuan. The key to the correct use of ethephon ripening is to master the upper cotton boll with a bell period of more than 40 days, a daily average temperature of 20 °C or more, and a spray of about 20 days from the frost period. The specific application time depends on the late maturity of cotton. Use 40% ethephon 100~150 ml per acre, 20~30 kg of water, and evenly spray the blue bell in the middle and upper part of the cotton plant. Do not use ethephon in the field, so as not to reduce the germination rate of the seeds; the normal cotton field can not be sprayed, so as not to cause a reduction in production.