Late growth management technology of cotton

After the "great heat" has passed, "starting autumn" is approaching. In the south of Fujian, cotton has entered the peak period of full flowering and there are currently major problems. First, due to the high rainfall in the early stages and the delay in chemical control, individual plots are growing stronger and the cotton plants are higher. Second, due to the recent high temperatures. , resulting in some cotton field aphids, spider mites and other pests are more emphasis on the growth of cotton to bring adverse effects. The current positive value of the cotton flowering period is also a critical period for the management of cotton in the middle and later stages. According to the climate characteristics of this year, we should seize the favorable opportunity, adjust measures to local conditions, and provide guidance on classification, effectively strengthen the management of cotton in the middle and later stages, and seize the cotton harvest.

First, fertilizer and water management in the middle of July on the basis of re-application of flower and bell fertilizer, should apply top cover fertilizer. First, before the "Autumn Festival", Urea urea 10-15 kilograms; Second, before the "summer heat" according to the seedlings Mushi urea 5 to 10 kilograms; Third, after August 20th combined pest control full promotion foliar spray fertilizer, that is, with 1 % ~ 2% of urea and 0.2% ~ 0.3% potassium dihydrogen phosphate mixture, spray once every 7 to 10 days, has been sprayed to the middle and late September, in order to facilitate the maintenance of the root leaves, to achieve the top peach autumn peach.

After flowering, the cotton field enters the peak period of water demand, and it will be affected by drought and water according to the weather and the actual conditions of the cotton field. The indicator for watering is watering at 4 o'clock in the afternoon with the wilting of the top leaves of the cotton plants. Generally, in the case of continuous raining for 7 to 10 days during the high temperature period in Fuqiu, grab the drought immediately before the outcrop in the dry phase to ensure the timely supply of water. In order to prevent cracking, the drought resistance of cotton plants can be improved and the shedding of bells can be reduced.

Second, pruning The current cotton fields have mostly played top. The time for cotton to hit the top is generally before August 10. The lower fruit branch leaves 2 to 3 fruit sections, and the middle fruit branch leaves 3 to 4 fruit sections. The upper fruit section number depends on the growth of the cotton plant. Pay attention to the leaves on the last fruit branch when you hit the tip of the flock. It is necessary to remove empty plants and empty branches in a timely manner to improve the ventilation and light transmission conditions. For axillary buds, follow along. After entering the flowering and boll period, the overgrowth of the cotton field can easily cause field canopy closure. The old leaves in the middle and lower parts of the main stem can be destroyed in batches. At the same time, the empty fruit branches can be removed and the fruit branches and leaves should not be avoided.

3. Pest Control In August and September, it was a period of multiple pests of cotton, and it was also a crucial period for Baole Baoling and insect population to seize cotton. Prevention and control of pests and diseases should adhere to the prevention and control strategy of "mainly attacking cotton bollworm, verticillium wilt, and other diseases and insect pests", and ensure that pests and diseases, especially bollworms, are harmed by principles of insects, disease application, mixed use, and cross-consumption. Control in the primary stage.

1. Cotton bollworm. When 100 larvae over 3 years old reach 5 heads, chemical control should be carried out. Chrysanthemums, organophosphorus pesticides or compound preparations with contact toxicity or stomach toxicity should be selected. The amount of liquid used for mu should not be less than 60 kg.

2. Fuxi. With 10% imidacloprid spray control 15 grams per acre, can also be used 3% acetamiprid 2000 times spray or 0.3% matrine spray 1000 times spray; prolonged drought, we must pay attention to the prevention of the occurrence of spider mites, the need for medication In the prevention and treatment, 15% broom scavenger (anthraquinone) 1500 times liquid + 8% abamectin 2000 times liquid mixture can be used, and the control effect on cotton leafhopper is significant, and can achieve “one spray and multiple treatment”. Effect.

3. Verticillium wilt in cotton. Flood irrigation should be changed to trickle furrow irrigation, the incidence can be reduced by 50%, timely drainage, to do irrigation, row matching. Field investigations were conducted in time to spray the diseased plants with 2% or 4 times of hymexazil or ethyl allicin to control the spread of the disease and mitigate the harm. At the same time as the spraying, the root canal treatment with one of the above-mentioned drugs within the range of one square meter of the diseased bacterium can significantly improve the effect of the spray.

Fourth, the chemical control of fertilizer and water conditions are good, growing strong enough cotton, should be 7 to 10 days after the top to be topped fruit branches or to grow 2 to 3 fruit sections, mu with 25% of Zhuang Zhuangsu 8 ~ 10 ml 50 to 75 pounds of water is sprayed once to control the fall of axillary buds, reduce fall-off, and achieve the top of autumn peach; for late-yielding and late-maturing cotton fields, when most cotton bolls reach 45 days or more, they can choose between “cold dew” and “frost”. For a period of 3 to 5 days, when the maximum daily temperature is above 20°C, mu 40% ethephon 100-150 ml, water 40-50 kg, evenly spray on sunny days.

Fifth, fine collection of fine picking In order to improve the quality and grade of cotton, it is imperative that fine fines be collected. In the process of cotton harvesting and sale, one must “pay attention to three searches, adhere to cleanliness, and implement five points.” That is, pay attention to three to find: find floor flowers, flowers, flowers, "eyes" flower (referring to the small flower head left in the shell); adhere to the net as: shell net, stalk net, Tian Jing, road net; implementation of five points : Grading, splitting, splitting, rolling, and sub-sales ensure that the flaps are returned to the warehouse and yields are harvested in abundance. Secondly, cotton bags should be used when harvesting and selling cotton, and chemical fiber bags should be banned to prevent the intrusion of foreign fibers.