Technical guidance on Field Management of Wheat before Winter in 2015

At present, the sowing of winter wheat is basically over, and most of them are in the emergence stage. Generally speaking, the soil moisture in various places is better this year, the sowing time is suitable, the sowing is concentrated, and the sowing quality is good. According to the forecast of the meteorological department, this autumn and winter will have the strongest El Nino event in 17 years, and will last until next spring, which is characterized by high winter temperature, reduced precipitation in some areas and sharp fluctuations in winter and spring temperature, which is disadvantageous to winter wheat production. In view of the abnormal climatic conditions, the National Agricultural Technology extension Service Center, together with the wheat expert guidance group of the Ministry of Agriculture, put forward technical guidance for field management before winter to strengthen "drought resistance, prosperity control, and frost prevention." do a good job in winter irrigation, suppression, chemical control, and pest control, cultivate strong seedlings before winter, and ensure safe overwintering.

(1) timely winter irrigation to resist drought and protect seedlings. In Huang-Huai, northern and northwest winter wheat areas, the wheat fields lacking soil moisture, returning straw, rotary tillage and unsolid soil should be watered at the right time to keep the seedlings safe through the winter. The winter irrigation time is generally chosen when the daily average temperature is stable at 3-4 ℃, the night freezes and the day dissipates, and the water can seep in time to ensure that it is completed before the heavy freezing. Advocate water-saving irrigation, prohibit flood irrigation, hoe in time after irrigation, loosen the soil to preserve soil moisture, prevent surface cracking, and prevent ventilation from damaging roots and seedlings.

(2) suppression and conservation of soil moisture, chemical control and prevention of prosperity. Timely suppression before overwintering, especially for wheat fields with cracks after straw returning and watering, can stabilize the soil, close gaps, reduce soil moisture, benefit seedling growth, and control prosperity and promote strength. Wheat seedling suppression should pay attention to dry but not wet, and should not be suppressed when the soil surface is wet or wheat seedlings are dewy; smooth surface ballast should be used, and corrugated ballast should not be used to prevent mechanical damage to wheat seedlings. For the wheat fields where sowing is too early and the population is too big and too prosperous, the growth inhibitor is sprayed to control the growth and become strong, and the seedlings can survive the winter safely.

(3) adjust the temperature with water to prevent the cold wave. For the high temperature, lack of cold resistance exercise of wheat, and early sowing and growing wheat fields, once they encounter cold wave weather, it is easy to freeze and kill the seedlings. It is necessary to pay close attention to weather changes, timely irrigation before cooling, improve soil moisture, adjust the microclimate near the ground layer, reduce the range of temperature change, and prevent cold wave frost damage. Once freezing injury occurs, appropriate amount of nitrogen fertilizer should be applied in time, and then watered to promote the growth of frozen wheat.

(4) Prevention and control of diseases and insect pests and chemical weeding. Pay close attention to the occurrence of diseases and insect pests such as red spiders, ground tigers and sheath blight, and make timely forecasts and control. Based on the treatment of spring grass in autumn, according to the grass phase, grass age, soil moisture and other appropriate use of chemicals, do a good job of chemical weeding before winter. From the middle of November to the first ten days of December in Huang-Huai-Hai and Northwest China, 3-4 leaf stage of wheat and 2 leaves and 1 heart to 3 leaf stage of weeds were carried out in Huang-Huai-Hai and Northwest China, and the daily average temperature in the middle and lower reaches of the Yangtze River was more than 5 ℃ before overwintering to ensure that the frost temperature below 0 ℃ would not be encountered within 7 days, so as to improve the chemical removal effect and avoid drug damage.

In addition, the northern wheat areas should prevent livestock and poultry from gnawing, ensure the normal growth of wheat seedlings and survive the winter safely, and the rice stubble wheat fields in the middle and lower reaches of the Yangtze River and southwest wheat areas should timely clear ditches and manage soil moisture, dredge the drainage and irrigation system, and ensure that drought and waterlogging can be drained.