Wheat topdressing with urea, can it be sprinkled together when it snows? Is fertilizer effective?

Urea is a common nitrogen fertilizer, which is easily soluble in water and takes effect quickly. It is deeply loved by farmers in the process of wheat planting.

From the seedling stage, tillering stage, jointing stage, heading stage and filling stage of wheat, farmers apply urea topdressing.

At present, wheat is in the tillering stage, and many places are about to usher in a new round of snowfall. Some farmers asked, after the snowfall, can you urinate in the field with the snowfall? Which effect is better, spraying before snow or spraying after snow? Is it necessary to pee? In this article, the little helper will talk about snowfall and urea application when planting wheat in detail. After reading it, everyone will have an answer.

According to the weather forecast released by China Weather Network, from 12 to 15, in the next 3-5 days, a new cold air will affect most parts of China. Due to the convergence of cold and warm air, snowfall will occur in parts of Henan, Hubei, Guizhou, Sichuan, Jiangsu and Anhui.

The wheat planting area in these areas is large, and some farmers want to promote the growth of wheat, so they want to urinate with the snowfall.

In the eastern part of Henan where the little helper is located, farmers who are busy topdressing in the snowy fields are seen every year.

In this regard, in the small helper high-yield exchange group, friends from other regions also said that this situation is more common.

However, only a small number of farmers do this, and most farmers will not brave the heavy snow to topdressing.

What kind of wheat fields need topdressing years ago?

According to the growth of wheat itself, not all plots need topdressing before the year. Only when wheat can't grow normally, farmers will topdressing (mainly urea) to improve the stress resistance of wheat seedlings and make them overwinter safely.

First, in the wheat field sown late, due to the relatively low temperature at the time of emergence, the seedlings will be weak yellow, resulting in weak seedlings. In this case, it is easy to cause freezing injury when encountering snowfall (accompanied by cooling), or freezing injury occurs after snow. Therefore, topdressing urea can promote the growth of wheat.

Secondly, some farmers rushed to apply urea when it snowed in the dry wheat field in the early stage.

After wheat was sown in May 438+1October in some wheat areas, the effective rainfall was less, the wheat in the field was in a dry growing environment, and farmers did not irrigate and water it, which led to the short growth of wheat seedlings due to lack of water.

As for the reason for not watering, the main reason is that there are no convenient irrigation conditions in the local area.

In case of snowfall, urea should be topdressing during snowfall. After the snow melts, urea can penetrate into the soil with snow water and be absorbed by wheat roots, thus achieving the purpose of supplementing nutrition and promoting wheat growth.

Thirdly, when wheat is sown, in the plot where no base fertilizer is applied, after the wheat enters the seedling stage, the growth of wheat is hindered due to insufficient nutrients, and the phenomenon of short growth, weak seedlings and yellow seedlings will appear.

Some farmers do not like to use base fertilizer when planting wheat, but choose multiple topdressing measures. In this case, topdressing is needed at seedling stage and tillering stage years ago, which saves a watering labor when it snows locally.

Fourthly, when weeding wheat years ago, herbicide damage occurred due to factors such as excessive dosage, wrong use method and low temperature. In this case, if the herbicide is less harmful, it can be relieved by spraying rape seed or potassium dihydrogen phosphate. If the herbicide damage is too serious, in addition to spraying the above chemicals, urea should be applied to alleviate it, so as to better promote the recovery of wheat growth.

The above situation is common in the actual planting of wheat, and it is necessary to apply topdressing to wheat.

If it is normal growing wheat, it does not need to be fertilized before the year, nor does it need to be fertilized with snow. This not only increases the planting cost, but also may lead to vigorous growth of wheat, thus increasing the probability of freezing injury.

Here, I would also like to remind you that when your own wheat field has grown vigorously years ago, you should stop topdressing urea or topdressing it when it snows. At this point, the focus of management is to control prosperity. Spraying flourishing control agent can promote the growth of wheat root system and improve its stress resistance, which is conducive to safe overwintering.

If urea is applied again, it will only grow stronger and stronger, which seems to be very high. However, stems and roots are weak and prone to freezing injury.

How about applying urea to the fields where wheat needs topdressing years ago? Which effect is better, spraying before snow or spraying after snow?

Regarding the above problems, the helper asked many farmers, and the main reason why he chose to urinate with snow was that after the snow melted, urea could dissolve in water and then penetrate into the soil for wheat to absorb.

It is considered that, like rainfall, the utilization rate of urea can be improved.

In fact, the use of snow urine element may have the opposite effect.

After urea is spread with snow, most urea can not directly touch the ground, but will adhere to leaves or snow. Snowfall means cooling down. Urea can be dissolved in water, but it should also have a suitable temperature. If the temperature is too low, not only can snowfall not melt quickly, but urea is also difficult to dissolve in water.

At normal temperature, such as above 20 degrees, it takes 1-2 days for urea to take effect after topdressing urea.

In winter, the temperature angle of snowfall even drops below 0 degrees, and it takes 3-5 days or even 5-7 days (or longer) for snowfall to melt. Coupled with the characteristics of urea itself, it may only melt in about 10 days. During this period, most nutrients volatilize, and the nutrients that wheat can absorb are limited, which greatly reduces the utilization rate of urea.

One more thing to understand is that urea cannot be directly absorbed by wheat. When urea is sown in the field, it needs to be hydrolyzed into ammonium carbonate under the action of urease, and then absorbed by wheat roots in ammonium bicarbonate and ammonium hydroxide. In this process, it also takes time, and of course it is also related to temperature. The lower the temperature, the longer the time, which further reduces the utilization rate of urea to some extent.

Therefore, under the above circumstances, the personal opinion of the little helper is that it is not recommended to use snow to apply urea.

So is it feasible before or after snow? The answer is yes, but there is some pressure.

If the way of sowing is adopted, it can be done before and after the snow, but the utilization rate will not be the highest.

Personally, I suggest that farmers wait until the snow melts and the fields can go in to work, and fertilizing in the furrow will improve the utilization rate.

To sum up, not all wheat fields need topdressing urea years ago, but the plots that need topdressing urea are not recommended to be sprayed with snow with the recent snowfall. When the snow melts, furrow application is more conducive to improving the utilization rate.

Finally, I want to give a suggestion to farmers. Don't watch others sprinkle fertilizer, but also sprinkle fertilizer yourself. Planting crops is not following the crowd. Adapting measures to local conditions is more conducive to crop growth.

Ask everyone, have you ever sprayed urea during snowfall in previous years?