Too much fertilization in the field at one time will cause the crop to burn the seedlings , which c

The solutions to this are:

Check the root system to see if there are white roots, and if the root system is normal, add a little fertilizer and water.

If the root system is not normal and there are no new roots, check whether there is any problem with the seedling soil. If there is a problem with the soil, you can consider changing the soil.

If the soil is not a big problem, you can use the rooting agent Prik to drench the roots.

Foliar sprays with slightly higher content of foliar fertilizer plus 802.

In addition, you can water more. Add some brassin.

Under normal circumstances, the concentration of cell fluid in plant root hairs is always greater than the concentration of soil solution, so the water in the soil solution penetrates into the vacuole through the cell wall, cell membrane and cytoplasm of the root hairs, and then gradually penetrates into the layers of cells in the epidermis, and finally enters the ducts, which are transported to other organs such as stems and leaves.

However, if the fertilizer is too much or too concentrated at one time, the concentration of the soil solution will be greater than the concentration of the root hair cell sap, and as a result, the water in the root hair cell fluid will penetrate into the soil solution, so that the root hair cells will not only not absorb water, but also lose water, so that the plant will wilt, that is, the proverbial "burning seedlings".

d. Large-scale watering and seedling burning is to apply too much fertilizer, and the concentration of fertilizer in the soil is too large, so it is necessary to reduce the concentration with more glue.

A14 2 is obviously wrong, it should be slow, 3 is wrong, it will not produce new species.

As far as I know, the hybridization of two species is so far.

Mules, and tigers and lions are crossbred to create new species.

Option 4 means that the best is the best chance to survive, so that the beneficial genes can be retained, e.g. a butterfly with a protective pattern is likely to survive, leaving the pattern gene.

14 should be right.

Water generously. Too much fertilization, more inorganic salts, and greater external osmotic pressure, which makes the cells lose water, so a large amount of watering reduces the external osmotic pressure.

Biology questions in the second year of junior high school.

Seedling burning is caused by the loss of water from the cells due to the concentration of aqueous solution in the soil greater than the concentration of cell fluid.

There is only one way to remedy this, which is to water more and reduce the concentration of the aqueous solution in the soil, so that the cells will not lose water.

The second option is B

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.

Because if the fertilizer is too much or too concentrated at one time, the concentration of the soil solution will be greater than the concentration of the root hair cell sap, and as a result, the water in the root hair cell sap will penetrate into the soil solution, so that the root hair cells can not only not absorb the water, but also lose the water, so that the plant wilts, which leads to the phenomenon of burning seedlings.

Chemical fertilizers are composed of a variety of different salts, so long-term and large application of these fertilizers composed of salts, when the fertilizer enters the soil, it will increase the concentration of the soil solution and produce osmotic pressure of different sizes, crop root cells not only can not absorb water from the soil solution, but pour the water in the cytoplasm into the soil solution, which leads to crop damage.

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.

Excessive fertilization sometimes does not cause the phenomenon of seedling burning, mainly part of the organic fertilizer.

Fertilizers will definitely burn the seedlings.

Chemical fertilizer, generally referred to as chemical fertilizer, is a fertilizer made by chemical and/or physical methods that contains one or several nutrients needed for the growth of crops. Also known as inorganic fertilizers, including nitrogen fertilizers, phosphate fertilizers, potassium fertilizers, micro fertilizers, compound fertilizers, etc., are inedible.

They have the following common characteristics: simple composition and high nutrient content; The fertilizer effect is fast, and the fertilizer is strong; Some fertilizers have acid-base reactions; Generally, it does not contain organic matter, and there is no effect of soil modification and fertilization. There are many types of chemical fertilizers, and their properties and application methods are quite different.

Fertilizers made by chemical methods that contain nutrients that are needed for the growth of one or several crops. Abbreviation for chemical fertilizer. Fertilizers that contain only one nutrient in a declarable amount are called unit fertilizers, such as nitrogen fertilizers, phosphate fertilizers, potassium fertilizers, and minor macro-element fertilizers and trace element fertilizers.

Chemical fertilizers that contain two or three of the three nutrients of nitrogen, phosphorus, and potassium and whose content can be indicated are called compound fertilizers or mixed fertilizers. The solubility of the active components of a fertilizer in water is usually a measure of the effectiveness of a fertilizer. Grade is the main indicator of fertilizer quality, which refers to the percentage of available nutrients or their oxides in fertilizer products, such as:

Percentage content of nitrogen, phosphorus, potassium, calcium, sodium, manganese, sulfur, boron, copper, iron, molybdenum, zinc.

Phosphate fertilizer, nitrogen fertilizer, and potassium fertilizer are chemical fertilizers that are in high demand for plants.

The macronutrients nitrogen, phosphorus and potassium in the soil usually cannot meet the needs of crop growth, and chemical fertilizers containing nitrogen, phosphorus and potassium need to be applied to make up for it. In addition to chlorine, which is not lacking in the soil, several other nutrients need to be fertilized with micronutrients. Chemical fertilizers are generally mostly inorganic compounds, and only urea is an organic compound.

Fertilizers that contain only one type of nutrient element that can be labeled are called unit fertilizers, such as nitrogen fertilizers, phosphate fertilizers, potassium fertilizers, etc. Any chemical fertilizer that contains two or more of the three nutrients of nitrogen, phosphorus and potassium and whose content can be indicated is called compound fertilizer or mixed fertilizer. Grade is the main indicator of fertilizer quality.

It refers to the percentage of available nutrients or their oxides in a fertilizer product.

According to the chemical properties, chemical fertilizers can be divided into:

1.Physiological acidic fertilizers. In the aqueous solution of chemical fertilizer, the grass absorbs too many cations from the fertilizer, and the remaining anions generate the corresponding acids, making the solution acidic, and most of the ammonium salts and potassium salts belong to this type of fertilizer.

2.Physiological alkaline fertilizer. If the anion absorbed and utilized by the forage grass is faster than the cation absorbed and utilized, the cation in the soil solution is excessive, and the corresponding alkaline compounds are generated, so that the solution becomes alkaline, such as calcium nitrate, magnesium nitrate, etc., are alkaline fertilizers.

3.Physiological neutral fertilizer. The rate at which the grass absorbs anions and cations is about the same, and the soil solution has a neutral reaction, such as potassium nitrate, ammonium nitrate, urea, etc.

According to the composition of nutrients, chemical fertilizers can be divided into: nitrogen fertilizer, phosphate fertilizer, potassium fertilizer, compound fertilizer, trace elements, etc. According to the use, chemical fertilizers can be divided into:

Base fertilizer and top dressing.

In addition, chemical fertilizers can also be divided into fast-acting fertilizers, slow-acting fertilizers, and long-acting fertilizers. Soil fertilizer, foliar fertilizer, etc.

It will cause the phenomenon of burning seedlings. Seedling burning refers to a phenomenon caused by excessive fertilization. Too much fertilization often does not produce the whole bed or a piece of seedlings or grows unevenly.

The root system of the fertilized seedlings is short, black, and does not take root, and when it is serious, it stops growing and turns yellow from the first leaf after the seedling emerges at the needle stage or grows to 2 leaves. In the case of such seedlings, as long as the film is not damaged by frost as soon as possible, the film should be watered during the day and covered at night. This is carried out until part of the fertilizer in the seedbed is washed off, and the rice seedlings are encouraged to take root, and the normal management can be carried out after the rice seedlings have new roots.

The state advocates soil testing and formula fertilization, according to the content of nitrogen, phosphorus, potassium and trace elements in the plot, and the ratio of compound fertilizer is conducive to the absorption of crops and cost saving. Appropriate application of microbial fertilizer can also reduce the cost of phosphorus and potassium decomposition of the soil. Major farmers do not understand the characteristics of chemical fertilizers, and the research and development of chemical fertilizers is to be diluted and dissolved in water before they can be absorbed, transported and utilized by plants.

There are many types of chemical fertilizers, and no matter what kind of chemical fertilizer it is, it is equivalent to waste if it is not diluted and dissolved with water.

It directly affects the growth and development of crops and the yield and quality of crops. The following is to the current farmers in the use of chemical fertilizers, there are a lot of improprieties and misunderstandings, to sort out, remind farmers and friends to pay attention to the use of chemical fertilizers, to ensure that chemical fertilizers play a good role, conducive to the growth and development of crops, many farmers for the content of chemical fertilizers, as well as the demand for fertilizers for different crops do not understand, for the lack of soil nutrients are rarely checked, fertilization is mostly to follow the feeling, or see how others use themselves.

Or maybe you think the more fertilizers you use, the better. The grain grown is also worse every year, especially the continuous heavy rains have washed away the soil, and the soil has become even more barren. In the past, there was no chemical fertilizer, and everyone had to carry manure to water the land when the farm was busy, and my parents also said that farmers are getting lazier and lazier in farming now.

One is dozens or hundreds of times higher than any farm fertilizer; The two and three elements are prepared, which saves the trouble in use. Therefore, the phenomenon of heavy chemical fertilizer and light farm fertilizer is widespread, and if you want fertilizer, you can buy it, so many farmers have not applied farm fertilizer in their rice fields for many years.

Use the same compound fertilizer. There are also people who use compound fertilizer when they are base fertilizer and top dressing. There are also some people who still have a little understanding of chemical fertilizers, they know how to apply nitrogen, potassium and phosphate fertilizers to crops, but they never pay attention to the application of trace element fertilizers.

However, even if many farmers have planted the land for many years and used chemical fertilizers for many years, they still have some big or small problems when using chemical fertilizers.