How to avoid seedling burning in the process of urea fertilization

Answer: In the process of crop cultivation, there is often a phenomenon that due to the improper use of fertilizer, the fertilizer components (including nutrients or other components and decomposition products) cause damage to the crop, and the crop has symptoms of damage, which we collectively refer to as seedling burning. After the fertilizer burns the seedlings, the direct impact on the crop is to damage the crop root system, and then affect the root system to absorb water and nutrients, so that the young roots of the crop become brown and die, and then affect the growth of the aboveground part of the leaves and young shoots of the plant.

If the burning of seedlings is severe, it will also lead to plant death, so in the actual crop cultivation management, it needs to be treated and treated correctly. It must be noted that the phenomenon of seedling burning is caused by improper fertilization, not only chemical fertilizers will burn seedlings, but organic fertilizers will also cause the occurrence of crop seedling burning, especially when the unrotted compost made of livestock urine is the most likely to cause the occurrence of seedling burning.

To avoid burning seedlings, urea seed fertilizer should master the following principles:

1) The dosage should not be too large, generally 75 112 kg of urea per hectare.

In the northern region, spring wheat is accustomed to use nitrogen and phosphorus fertilizers as seed fertilizer, mixed with seeds. When urea is used as a seed fertilizer mixture, it should not exceed 52 kg per hectare;

2) Field crops should be applied urea strips or holes 36 cm below the seed slope, and after fertilization, slightly mix to mix the fertilizer soil, or cover a layer of soil and then sow and fertilize the seeds separately.

3) It is best to use a 48-row seeder for spring wheat, interlaced sowing, and interlaced sowing fertilizer. With this method, the fertilization per hectare can be increased to 225 300 kilograms, and the seeds and seedlings will not be burned, and the yield increase effect is remarkable.

4) Try not to apply urea alone or continuously for a long time. For example, in the production and fertilization of fruits and vegetables, other nitrogen fertilizers can be used, or alternately used with ammonium carbonate and ammonium sulfate to prevent fertilizer damage caused by the accumulation of biurea. At the same time, it is necessary to implement the formula fertilizer application of various nutrients, reasonable matching, and good coordination to achieve nutrient balance.

5) Do not apply as seed fertilizer to prevent urea biuret from entering the seeds and seedlings and affecting germination and seedling development. If it needs to be applied, it should be kept at a certain distance from the seeds, generally should be applied about 3 cm under the seeds and fully mixed with the soil and the moisture is suitable, and the amount of urea per mu should not exceed ten catties.

6) It is necessary to grasp the application concentration and avoid excessive concentration. This is very important, especially when used as seed fertilizer, foliar fertilizer and root watering, excessive concentration will inevitably cause fertilizer damage.

Be sure to prescribe the right medicine, pay attention to the concentration when fertilizing, pay attention to the ratio, don't apply too much at one time, be sure to do a good job of drainage, and don't use it when the temperature is relatively high.

In the process of fertilization, we must pay attention to the frequency of fertilization, and also pay attention to the proportion of water to coordinate, so as to avoid the phenomenon of burning seedlings.

It is necessary to pay attention to the amount of fertilizer, pay attention to the time of fertilization, do not apply too much fertilizer at one time, choose the appropriate amount according to the situation of the crop, dilute it with water in advance, and do not compost too much fertilizer.

When the salt in the soil is higher than the salt in the root system of the crop, the water in the crop will flow to the soil with a higher concentration, so that the capillary roots of the crop not only cannot absorb the water, but also push the water, causing the crop to lack water and wilt. If it is excessive fertilization and the concentration is too high to burn seedlings, the method of frequent irrigation and drainage can be adopted to remedy as much as possible and irrigate enough water, so that the fertilizer in the soil is dissolved in water, and then drained to reduce the fertilizer concentration in the soil.

After half an hour, you can continue drip irrigation with the solution of water and fertilizer, and finally drip irrigation for half an hour with water. This can dilute the concentration of fertilizer in the soil, prevent root burning, and also allow the fertilizer to spread farther with water, so that my roots can better absorb it. In order to ensure the safe application of fertilizer.

Generally speaking, the basal fertilizer and mouth fertilizer applied at the time of sowing are recommended to be applied to the side of the seed 5 cm and the depth is about 10 cm; When topdressing, the fertilizer is also applied to the side of the root system as much as possible, keeping a certain distance from the root system.

If the root system does not absorb water, it will generally cause the phenomenon of chemical fertilizer burning the roots. When the crops in the field burn seedlings, then, the root system of the crops will generally wither, and then do not absorb water, and generally the leaves of the plant will appear yellow, the phenomenon of falling leaves. or organic fertilizer that is not rotten, or the concentration of topdressing outside the root is too high.

When the seedlings are fertilized, the phenomenon of leaf loss and root rot occurs. Nutrient soil should be reasonably prepared, well-rotted organic fertilizer should be used, and nitrogen, phosphorus and potassium fertilizers should be reasonably coordinated and stirred evenly.

Secondly, in the use of chemical fertilizers, it is recommended to use bio-organic fertilizer, humic acid fertilizer, fungus fertilizer and well-rotted farmhouse fertilizer, which has high organic matter content and also plays an important role in improving soil structure, and more importantly, it can effectively reduce the damage of biuret to crops. In order to prevent chemical fertilizer from burning seedlings, it is necessary to apply it in strict accordance with the measurement specified in the chemical fertilizer, and whenever there is chlorine in the chemical fertilizer, it is necessary to isolate the fertilizer or do deep fertilization, only in this way can we get high-quality and healthy seedlings.

When buying urea, see the content of "biuret", generally the content of "biuret" should be less than, and more than can not be sown with seed fertilizer or seed fertilizer; More than 1%, can only be used for top dressing, top dressing as far away from the root system as possible, to avoid fertilizer damage; More than 2% is unqualified urea, buy with caution.

Crops that are highly sensitive to biuret should try not to use urea and compound fertilizers containing urea as nitrogen fertilizers, and know that it is harmful and do not use it, which is the best way.

To do the isolation of seed fertilizer, generally use compound fertilizer to make seed fertilizer, urea is used as top dressing in most cases to raise seedlings, the distance between the seeds and the compound fertilizer is about 2-3 cm, and the soil is returned to the soil in time after sowing, and the soil moisture is insufficient to reduce the concentration of the solution. This not only isolates the seeds, but also helps to promote the growth of the root system after the seeds emerge, increases the absorption area of the root system, and is the basis for the size of the strong roots.

1. Too much fertilizer leads to an increase in the salt concentration in the soil, or the fertilizer is in direct contact with the crop roots, resulting in too high a nutrient concentration in the soil around the roots, and the water in the crop roots will flow out to the soil (the principle of water flow direction is from low concentration to high concentration), and finally the phenomenon of seedling burning occurs. 2. The application of unrotted organic fertilizer is also prone to seedling burning, such as unrotted chicken manure. 3. "Seed fertilizer in the same bed" is also prone to seedling burning.

1. The reason why too much fertilization will cause seedling burning

1. Excessive fertilization will increase the concentration of salt in the soil and water, or the fertilizer will be in direct contact with the root system of the crop, so that the nutrient concentration in the soil around the root system is too high, and the principle of water flow direction is to flow from low concentration to high concentration, which will lead to the outflow of water in the root system of crops (or seeds) into the soil, and finally the situation of burning seedlings.

2. Unrotted organic fertilizer (such as chicken manure) contains a large number of salts, germs, and insect eggs, which will increase the cost and difficulty of controlling pests and diseases after application, and it is also easy to burn roots and seedlings.

3. The depth of fertilization, the distance between fertilizer and seeds need to be grasped, and the fertilization method of "planting fertilizer in the same bed" or "fertilizer in the deep position under planting" should not be used, otherwise it is easy to burn seedlings.

Second, how to remedy excessive fertilization and burning seedlings

1. If the crop can not be saved, it is necessary to replant or other crops in time, and avoid the original fertilization position when replanting or planting, so as to prevent the recurrence of seedling burning.

2. Replace the soil, re-watering and fertilizing. If too much root fertilizer is applied and the seedlings are burned, the undissolved fertilizer on the soil surface can be removed and then watered.

3. If you are planting aquatic crops such as rice, you need to immediately use the method of frequent irrigation and drainage to change the water to discharge the biuret and reduce the concentration of fertilizer.

4. After detoxification, an appropriate amount of nitrogen, phosphorus and potassium compound fertilizer (or spraying foliar fertilizer with a lower concentration) should be applied to promote the growth of seedlings, and the corresponding bacterial fertilizer can also be used.

5. Do a good job of shading, and if necessary, you can spray some brassinin to help the growth of new leaves.

Urea can be applied to grow vegetables.

Compound fertilizer can also be applied, but urea is generally appropriate. Urea can promote the better growth of vegetables, and the growth period of vegetables is relatively short, so urea can play a better role, so that vegetables can be replenished in time to supplement the lack of nutrients; Compound fertilizer is generally suitable for use as base fertilizer, because its fertilizer effect period is relatively long-lasting.

1. Urea or compound fertilizer for growing vegetables

Both urea and compound fertilizer can be applied to vegetables, but urea is generally recommended because it is more suitable for plants. Urea can promote the better growth of vegetables, and because the growth period of vegetables is not very long, urea can better exert its nutrients, so that it can timely supplement the lack of nutrients for vegetables; At the same time, vegetables produce a lot of chlorophyll in the process of growth and development.

Therefore, urea is more suitable for vegetables than compound fertilizer, and compound fertilizer is generally suitable for use as base fertilizer, because its fertilizer effect period is relatively long.

Second, how to fertilize without burning seedlings

1. Do not apply unrotted organic fertilizer.

2. Rational use of chemical fertilizer, the use must be applied in accordance with the appropriate concentration, especially nitrogen fertilizer can not be applied too much at one time, if urea is used as foliar fertilizer, the concentration should not be exceeded, and as long as the leaves of the crop are wetted when applied.

3. Increase the application of organic fertilizer, organic fertilizer to cation.

It has a strong adsorption capacity, so that its concentration is not too high, and it can also improve the buffering capacity of soil nutrients, so that the occurrence of fertilizer damage can be reduced to a certain extent.

4. When fertilizing, the fertilizer should be about 10 cm away from the roots, and it should be applied deeply, and the soil should be covered immediately after fertilization; Top dressing when the soil is dry requires timely irrigation to reduce the concentration of fertilizer.

Answer: After the phenomenon of burning seedlings, you can change the water by the method of frequent irrigation and drainage, when the fertilizer in the soil is fully dissolved in the water, and then drain the water, and transplant the seedlings into the new soil after the treatment, in order to promote it to recover its vitality as soon as possible, you can reasonably supplement the fertilizer. In order to ensure that urea can work normally, in addition to controlling the application amount to prevent the phenomenon of seedling burning, it is also necessary to pay attention to the application time, and urea should not be used before and after rain and in hot weather.

1. Remedies for urea seedlings

1. Remedy.

After the phenomenon of burning seedlings, it is necessary to change the water by means of frequent irrigation and drainage, reduce the concentration of urea, and then drain the water after the fertilizer in the soil is fully dissolved in the water, and then transplant the seedlings to a better soil and make reasonable fertilizer to restore the vitality of the seedlings.

2. The correct way to use urea.

1) generally need to determine the spraying concentration according to the type of crops, the spraying concentration of cereal crops is generally, if in the flowering period, the application concentration is slightly lower, the spraying concentration of nightshade crops is generally, the spraying concentration of vegetables and cucumbers is general, and the spraying concentration of apples, pears, grapes and other fruit trees is generally.

2) The application concentration should not be too high to prevent the leaves of the crop from being burned.

3) Urea should not be sprayed before and after rain, and it is not advisable to spray urea if the weather is hot, and it can usually be sprayed before 10 am and in the evening.

Second, the difference between urea fertilizer and compound fertilizer

1. The nutrient elements are different.

1) Urea fertilizer: The main element is nitrogen (N).

2) Compound fertilizer: It contains more elements, such as nitrogen, phosphorus, potassium or other medium and trace elements, but in most cases, it is mainly a large number of elements.

2. The role played is different.

1) Urea fertilizer: used as top dressing, for example, when the corn seedlings grow to a certain height, reasonable spraying urea is conducive to the growth of corn seedlings.

2) Compound fertilizer: It can not only be used as top dressing, but also as base fertilizer, but it is still mostly used as base fertilizer.

3. Different usage.

1) Urea fertilizer: After dissolving urea with water, the method of foliar spraying is used to supplement nitrogen elements for crops, and the method of digging pits and covering soil at the roots is also used to fertilize.

2) Compound fertilizer: first dig a pit, and then bury the compound fertilizer around the root system of the crop to provide nutrients for it.