Dry and hot wind will hit many places and the highest wheat yield will be reduced by 20%

At present, winter wheat in North China and Huanghuai is at the critical stage of flowering, pollination and grain filling
.
According to the prediction of the Central Meteorological Observatory, in the coming week, the average temperature in most of the northern winter wheat areas will be higher than normal in the same period of the year, and that in North China and other places will be 4 to 5°C higher
.
From the 17th to the 19th, Beijing, Tianjin, Hebei, Henan, Shanxi, northern Shandong and other places continued to be sunny and hot.
The highest temperature can generally reach above 32℃.
The relative humidity of the air is low.
The wind force is generally greater than 3 m/s in the afternoon, and the soil in some areas Due to the deviation of moisture content, “hot and dry wind” will appear in the winter wheat area.
From 18 to 19, the highest temperature in parts of central and southern Hebei and northern Henan will reach about 37°C, and there will be moderate to severe “hot and dry” weather.
The unfavorable filling of winter wheat will result in a decrease in the filling rate of winter wheat and a reduction in grain weight
.
What is wheat dry hot air? Dry hot wind is a common meteorological disaster in the later stage of wheat growth.
Generally, wheat yield can be reduced by 5%-10% after being damaged, and some serious ones can reach more than 20%
.
After the hot dry wind occurs, the water in the wheat body is quickly consumed, which destroys chlorophyll and other pigments, hinders photosynthesis, and makes the plants dry quickly from bottom to top
.
It is now the wheat filling period.
If the wheat ears are not fully filled due to the dry and hot wind, the wheat will "ripen" ahead of time, the wheat kernels will become dry, and the kernel weight will decrease, leading to a serious reduction in wheat production
.
It appears in North China, Northwest China, and Huanghuai regions during the late spring and early summer.
They are generally divided into two types: high temperature and low humidity and heat and dry after rain, all of which are mainly high temperature hazards
.
The meteorological indicators of dry and hot wind damage winter wheat and spring wheat are different, and they are also inconsistent between regions
.
Generally speaking, for high-temperature and low-humidity type: light dry hot wind means that the maximum daily temperature is greater than or equal to 29-34°C, and the wind speed at 14 o'clock is greater than or equal to 2 to 3 meters per second
.
Heavy dry hot air means that the daily maximum temperature is greater than or equal to 32-36°C, the relative humidity is less than or equal to 20-30% at 14 o'clock, and the wind speed is greater than or equal to 2 to 4 m/s at 14 o'clock
.
This is the main type of wheat in northern China, which will mainly cause wheat dry tips, wheat kernels withered and dry wheat, which will affect the yield
.
Hot and dry after rain: There is a rain process within 10 days before the wheat matures, and the temperature becomes clearer and warmer after the rain.
The daily maximum temperature reaches 30℃ or more within 2 to 3 days.

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This situation will mainly cause the withering and maturity of wheat
.
Preventive measures for hot and dry wheat 1.
Pour the grout water well
.
After the wheat blooms, it enters the wheat filling stage.
At this time, high temperature, drought, and strong wind force the evaporation of air and soil moisture to increase.
Pouring the grouting water can maintain suitable soil moisture, increase air humidity, delay the premature root senescence, and enhance leaf photosynthesis To prevent or reduce the harm of dry and hot wind
.
Pay attention to stop pouring in wind and rush to pouring without wind
.
The grouting water should be poured at the beginning of grouting
.
2.
Pour wheat yellow water skillfully
.
About 10 days before the wheat matures, according to the wheat population, weather conditions, and soil moisture, watering the wheat yellow water before the hot dry wind can significantly improve the field microclimate conditions and reduce the damage of the dry hot wind
.
The wheat yellow water is poured in the milk maturity period to the wax maturity beginning period
.
3.
Spray fertilizer on foliage
.
From the flowering of wheat to the early stage of filling, use 1%-2% urea solution, 0.
2% potassium dihydrogen phosphate solution, 2%-4% superphosphate leaching solution or 15-20% plant ash leaching solution as foliar spray fertilizer, each time per mu Spraying 20-100 kilograms can accelerate the growth and development of wheat in the later stage and prevent or reduce the damage of dry and hot wind
.
4.
Spray vinegar on the leaves
.
In the early stage of wheat filling, spraying with 0.
1% acetic acid or 1:800 vinegar solution on the leaf surface can reduce the opening angle of the stomata on the leaves, inhibit transpiration, and improve the ability of wheat plants to resist drought and dry hot wind
.
5.
"One spray and three prevention" in the later stage of wheat is one of the effective measures to prevent and reduce pests and diseases, dry hot wind and other hazards.
Therefore, it should be sprayed 2-3 times according to the occurrence of pests and weather changes, which can effectively increase the grain weight.
Prevent dry and hot wind
.