Eight-character formula for field management of winter wheat in spring

Spring is the key period to determine the number of spikes per mu, grain number per spike and grain weight of wheat. Strengthening field management in spring according to seedling situation is the key to realize high yield of wheat. In terms of management, we should focus on implementing the eight-character key points of "pressing, hugging, clearing, chasing, pouring, controlling, preventing and resisting".

Press: press wheat in early spring. Pressing wheat in early spring can settle the soil, bridge the soil gap, increase soil moisture, preserve soil moisture, prevent cold, control prosperity and prevent toppling, and promote the root system to return to green early. In the appropriate period of suppression, the wheat was pressed twice from the surface layer of the wheat field from thawing and returning to the green stage to the green stage, and the overgrown wheat field was suppressed for 2 or 3 times from turning green to starting stage, which could restrain the aboveground growth and play the role of controlling prosperity and strengthening and preventing toppling. Wheat fields with extensive and bumpy soil preparation during autumn sowing should be suppressed in time after soil thawing in early spring. Repression should be carried out "two should be early and three should not be suppressed". That is, the wheat field with poor soil preparation quality should be suppressed early, and the wheat field with bad soil moisture should be suppressed early, turn on the soil capillary to increase soil moisture; do not press wheat in the early morning, do not press wheat when soil moisture is too large, and do not press wheat when the plant freezes, so as not to crush wheat leaves and destroy soil structure.

Cuddle: that is, hoe and cuddle wheat. Hoing and loosening soil has the functions of raising temperature, preserving soil moisture, promoting weak to strong, controlling prosperity and turning to health, and promoting early root development and rapid growth of new tillers of wheat seedlings. Generally before and after turning green, first suppress and then hoe and cuddle wheat, the general wheat field hoe depth of 1 cm 2 cm, there is lodging danger of hoe depth of 3 cm.

Clear: that is to clean up the winter mulch in time. If the measures of covering soil and manure against cold are taken in winter, the wheat will be cleaned twice in the period of returning to green, so as to prevent the dung from affecting the photosynthesis of leaves.

Topdressing and watering: that is, topdressing and watering. Topdressing and watering should be done "five looks", and fertilizer and water should be checked scientifically.

The operation of fertilizer and water in spring depends on soil moisture, seedling situation, period, weather and soil fertility.

For those wheat fields that rush to sow soil moisture and seal off frozen water too early before winter, or that are not irrigated with frozen water, or where the temperature is more than 3 ℃ in the middle of March, choose a sunny day and carry out fine watering with small water from 10:00 to 4 p.m., and strictly control the amount of water, and do not flood; in case of a sharp drop in temperature, stop watering immediately and wait for the temperature to rise again to prevent frost injury.

The three kinds of wheat fields with poor soil moisture and the total number of stems per mu less than 450000 were mainly promoted, the first fertilizer was irrigated in the turning green stage, 5kg of urea per mu was applied with watering, and the second fertilizer was irrigated at the jointing stage, followed by 10 kg of urea per mu. In the second class wheat field with good soil moisture and total stem number of 450000 ~ 600000 mu, fertilizer and water should be irrigated for the first time in the period of wheat emergence, combined with topdressing urea 10 kg / mu. Among them, the wheat fields with weak wheat seedlings and insufficient wheat seedlings can be fertilized and watered from the early stage to the middle stage, and the wheat fields suitable for the population should be fertilized and watered for the first time in the later stage of rising.

When the soil moisture is good and the total stem number per mu is between 600000 and 800000, the first fertilizer and water can be postponed to the jointing stage, combined with watering urea 1215kg per mu.

The prosperous seedlings with a total stem number of more than 800000 per mu and the danger of lodging should be suppressed by ploughing before jointing to control the growth of the population. Generally, it can be watered and fertilized at the later stage of jointing, applying 8kg urea per mu.

Control: that is, chemical control against collapse. Chemical control can effectively shorten the basic Internode length and improve the ability of lodging resistance. For high-yield fields, or a small number of wheat fields with more than 800000 stems per mu before winter due to early sowing and excessive density, or wheat fields with excessive fertilization, or plots with poor lodging resistance, during the rising period, use 10% Guoguang Aifeng wettable powder 37.5% 50g per mu, or 20% Zhuangfengan EC 25kg 30ml, spray 30 kg water evenly, and strictly control the dosage, no weight, no leakage and no drift.

Prevention: that is, comprehensive prevention and control of diseases, insects and weeds. Spring is the season of frequent occurrence of winter wheat diseases, insect pests and weeds, so we should pay attention to timely prevention and control. The main pests of wheat in spring are red spider and red midge, and the main diseases are root rot and total erosion disease.

Wheat red spider can be controlled by Puke water agent or avermectin spray. The first control of wheat red midge is from April 20 to 30 in eastern Hebei. Chlorpyrifos 2kg / mu is mixed with 20kg / mu of fine fluvo-aquic soil, and the soil moisture is evenly spread in the wheat field. Water should be watered for the second time in the period of wheat heading and flowering. Kuaishaling and deltamethrin were used to control the adults of wheat red midge and wheat aphids.

Root rot disease and total erosion disease can be controlled by root irrigation with 500 times of 20% triadimefon.

Weeds in wheat fields. In the starting period of wheat, when the weeds are 2-3 leaves, the clear and windless weather is selected for chemical weeding. The dosage of drugs should be strictly controlled during chemical elimination to avoid drug damage.

Imperial: timely prevention of low temperature and freezing injury in spring. After the wheat turns green, you should pay attention to listen to the weather forecast and pay close attention to the weather changes. If a substantial drop in temperature is predicted in the near future, plant growth regulators such as "Bibu" or Tianda-2116, Yunda-120, Lvfeng 95 and other plant growth regulators should be sprayed before the cold wave. Spraying 3 grams of water per mu and watering it within 2-3 days before the cold wave can effectively prevent frost injury in early spring. If low temperature and freezing injury occurs, remedial measures should be taken immediately, spraying plant growth regulators such as "Bihuo", Tianda-2116, Lvfeng 95, applying about 10 kg urea per mu, and ploughing to preserve soil moisture, improve soil temperature, promote root development and increase the number of tillers. Make up for the loss of the main stem, repair the damage, and alleviate the freezing injury.