Why do plants die after urea is applied?

Urea you administer.

It is not diluted, but poured directly on the surface of the soil. If the concentration of urea soaked in the soil is higher than the concentration of intracellular fluid in the root cells of the plant, the water will flow out of the cells, and the cells that have lost water for a long time will die, and the plant will have rotten roots, and then the whole plant will die. In addition, it is not advisable to water the plants at noon when the temperature is at their highest, as this will only harm the plants and cause them to die of exhaustion.

We are high school biology.

These examples are all mentioned.

Urea is generally not used as a fertilizer for raising flowers, and special flower fertilizers can be used for raising flowers. They are sold in the flower and bird market. Urea has a high nitrogen content and is suitable for top dressing, usually foliage plants need this fertilizer, and it is best to spray it with a sprayer after dissolving with water, which is safer.

Not to exceed the concentration. According to your description, the urea was used too much at that time, did you dissolve the urea in time, and the concentration was too large and the flower burned to death. Urea is broken down into ammonium bicarbonate by bacteria in the soil, in the form of ammonium salts** plants.

If you want to use nitrogen fertilizer, you can go to a chemical store and buy ammonium nitrate to use, which is safer than urea.

The amount of fertilizer was too large and burned to death. It is recommended to take a small amount of urea dissolved in water and apply it.

What good things can not be used in excess, the concentration of fertilizer is too high will directly damage the roots of the plant, which will lead to plant decay, I think domestic flowers should not use such a high concentration of chemical fertilizer, please refer to it, the plant will also be uncomfortable hehe, don't be sad, I hope you can raise more beautiful flowers.

Urea is a high-concentration nitrogen fertilizer, neutral fertilizer, suitable for a variety of soils and plants, often used as a base fertilizer or top dressing in the agricultural planting process.

One, why can't you water immediately after applying urea.

Urea is a white granular crystal that is slightly hygroscopic and completely soluble in water. It is a neutral fertilizer. After the application of urea, there is no urea left in the soil, which is called non-auxiliary fertilizer.

But it has one outstanding feature. The thalidomide nitrogen contained in it cannot be directly absorbed by crops. It must be converted to ammonium nitrogen under the action of soil microorganisms before it can be used.

If irrigation is carried out immediately after the application of urea, it will be dissolved by water. Due to the weak adsorption between soil colloids and urea, urea has great fluidity in the soil, especially flood irrigation will make urea drip to the deep layer. Reduced fertilizer efficiency.

Therefore, it is not advisable to irrigate urea immediately after topdressing, and it is not advisable to topcoat urea before rain.

Second, the choice of urea topdressing and watering.

After understanding some of the characteristics of urea, let's talk about urea topdressing with the example of growing corn in dry land and rice in paddy fields.

1) Top dressing corn with urea. Urea is used for top dressing of corn. When topdressing, farmers dig a pit about 12 centimeters deep and apply urea at a distance of about 15 centimeters from the corn roots.

In order for corn to better absorb urine nutrients, farmers do not choose to top dress corn when the soil is dry, but dig when the soil moisture is more suitable after the rain stops.

It is very common to top dressing rice with urea. The method is to drain the water in the rice fields, saving less. After urea is applied, it usually takes 5-7 days so that the water does not fall into the ground.

Third, the following issues should be paid attention to when using urea.

1) Generally, it is not directly used as seed fertilizer. Since urea contains a small amount of biurea, generally less than 2%, diurea is harmful to seed germination and growth. If you have to make seed fertilizer, you can separate the seeds from the urea and put them in the ground.

Do not soak or finish the seeds with urea. (2) When the content of diurea is higher, it cannot be used as top dressing for outer roots. (3) After urea is converted into ammonium bicarbonate, it is easy to decompose and volatilize on calcareous soil, resulting in nitrogen loss.

Therefore, deep cover soil should be used.

Urea itself cannot be directly absorbed by plants, it needs to be converted to ammonium carbonate by urease. Secondly, urea can be soluble in water, and it may be counterproductive if the concentration is not grasped well.

It causes the plant to die, there is no way to grow normally, it leads to a decrease in yield, and causes the whole plant to wither, which will bring great harm to the land.

Urea is an amide nitrogen fertilizer, it should be converted into ammonia nitrogen in order to be absorbed and utilized by crop roots, the transformation process is different due to soil quality, moisture and temperature and other conditions, the time is long and short, generally after 2-10 days to complete, if the application is immediately irrigated and drained or applied in dry land before heavy rain, urea will be dissolved in water and lost. Generally, irrigation should be carried out 2-3 days after application in summer and autumn, and 7-8 days after application in winter and spring.

It can cause plants to die, which is very dangerous, and it will cause the plants to be burned to death, and there is no way to grow normally, resulting in the death of many plants.

When using urea, this fertilizer should not be watered directly to the plant, watering will dilute the urea components, and may cause the plant roots to be burned by the fertilizer.

1. Urea contains biuret, and the application rate is too high, which often hurts the crops, especially when fertilizing on the foliar surface or near the seeds.

2. Biuret poisoning is manifested as yellowing of leaves, and rice seedlings sometimes have whitening. On citrus, coffee and pineapple, yellowing and curling of leaves, loss of green between the veins of corn leaves, short growth, and inability to stretch leaves can be seen.

3. Biuret can be decomposed by microorganisms in the soil, so as long as there is a certain distance from the crop seeds when applying urea, it will generally not cause harm.

Excessive application of urea will cause unnecessary waste and "fertilizer", which cannot be absorbed by the soil before being converted to ammonium carbonate, and is easily lost by rainwater and easy to harm crops. At the same time, if urea is applied too much, most of it will be lost and enter the groundwater, which will lead to ammonia pollution in the water body, resulting in nitrite deposition, which will seriously affect the safety of humans and animals.

Urea is a kind of high-concentration nitrogen fertilizer, which is a neutral fast-acting fertilizer, but a small amount of biuret will be produced if the temperature is too high in granulation, which has an inhibitory effect on crops. The content of urea biuret for fertilizer should be less than. When the content of biuret is more than 1%, it can not be used as seed fertilizer, seedling fertilizer and foliar fertilizer, and the urea content in other application periods should not be too much or too concentrated.

Hello! Remedial measures should be taken for fertilizer damage that has occurred: too much urea can be alleviated by topdressing phosphorus fertilizer, potassium fertilizer, or foliar spraying of potassium dihydrogen phosphate, plant ash liquid, etc.; In addition, the soil at the fertilization site can be dug up, the soil in the hole can be watered with water, the soil fertilizer concentration can be diluted, and the coarse roots that have been rotted and dead can be cut off, and then covered with new soil, and the upper dead branches can be pruned at the same time.

Hello! Remedial measures should be taken for fertilizer damage that has occurred: too much urea can be alleviated by topdressing phosphorus fertilizer, potassium fertilizer, or foliar spraying of potassium dihydrogen phosphate, plant ash liquid, etc.; In addition, the soil at the fertilization site can be dug up, the soil in the hole can be watered with water, the soil fertilizer concentration can be diluted, and the coarse roots that have been rotted and dead can be cut off, and then covered with new soil, and the upper dead branches can be pruned at the same time.

It was a small pear tree that was just planted this year.

Deal with it quickly to avoid burning seedlings too much.

How to deal with it.

I said above, look at it.

The simplest and most direct is to keep watering and dilute it with a lot of watering.

How to spray dihydrogen phosphate in proportion.

I can't keep watering if I plant too much.

Generally, the proportion concentration of potassium dihydrogen phosphate foliar fertilizer is 300-400 times, and it is advisable to water it, and then spray potassium dihydrogen phosphate.

Yes, deal with it as soon as possible.

Excessive use of urea can burn out plant roots, causing stunted growth and death of crops.

Solution: 1) Carry out flood irrigation, dilute the concentration of fertilizer with water, disperse the infiltration fertilizer, and reduce the harm.

2) For the strip application of urea, it can be cultivated in deep on the strip ditch to release the ammonia converted by urea. Reduces the damage of ammonia to the root system in the soil.

Note: When cultivated at high temperatures, ammonia will damage the leaves.