What s the matter with the yellowing of corn leaves, only herbicides were applied

See if it is a herbicide, high temperature can not play herbicide, corn is too big can not be played, as long as it is a phenomenon after the corn-specific herbicide is hit, the leaves will turn green by themselves after more than a week of yellowing.

For fertilizer damage caused by nitrogen excess, an appropriate amount of plant growth regulators such as arthrothramine and paclobutrazol can be sprayed to alleviate it. If there is a surplus of phosphorus, nitrogen, potassium, zinc and other micro-fertilizers can be added to adjust the reasonable ratio between the elements. In most cases, the fertilizer damage caused by trace elements occurs in spots, and as long as field management is strengthened, it has little impact on the yield per unit area of maize.

Hello, after the herbicide, the solution to the yellowing and wilting of corn seedlings is as follows:

1. Cultivating the field, continuous irrigation and soaking field drainage, and repeated flushing to alleviate pesticide damage.

2. Combined with watering, increase the application of rotting farmhouse fertilizer, accelerate the development and regeneration of roots, and restore the physiological function of the damaged maize, so as to reduce the harm of herbicides to crops;

Strengthen the cultivation of loose soil, break the soil compaction, enhance the air permeability of the soil, increase the ground temperature, promote the activity of beneficial microorganisms, accelerate the decomposition of soil nutrients, enhance the absorption capacity of the root system for nutrients and water, so that the plant can resume growth and development as soon as possible, and reduce the loss caused by pesticide damage.

3. Micro-fertilizers such as zinc, iron, and aluminum can be used to promote crop growth and effectively reduce pesticide damage.

There may be some pesticide damage if the herbicide is used too much, and under normal circumstances, it is to spray some brassinin and foliar fertilizer to alleviate it.

This is damaged by pesticides, and can only be made up for by spraying nutrients, combined with watering, and topdressing some urea to improve the growth of corn.

In this case, it is necessary to do a simple cleaning with water. If the herbicide is not cleaned in time, I think it will affect the yield of corn.

Generally, the appropriate period for the use of post-emergence herbicides in corn should be after 2 leaves of visible leaves of corn to before 5 leaves of visible leaves. If the drug is used at the 5 and 7 leaf stage, it should be used between the corn rows to avoid spraying the liquid into the heart leaves.

For the whole growth period of corn, we mainly use herbicides in 3 periods:

The first period is the post-sowing and pre-emergence herbicides.

After corn sowing and before emergence, closed herbicides are used. Now that the maize has been planted in most areas, it is the best time to use pre-emergence herbicides.

The second period is the early post-emergence herbicide.

In the 3-5 leaf stage of corn emergence, that is, when the weeds are about in the 2-4 leaf stage, this time is the best period for weeding.

In general, systemic selective herbicides are recommended. For some areas where wheat was harvested earlier, such as southern Henan, corn has been sown, and now corn is almost in the 3-leaf stage, which is the appropriate period for the use of herbicides in the early post-emergence period.

The third period is herbicides in the middle and late post-emergence period.

Generally speaking, herbicides are used well before and after corn seedlings, and there will not be many weeds in the middle and late stages of corn seedlings. However, some growers did not do a good job of weed control measures in the early stage, that to the middle and late stage of corn seedlings, there will be reeds, spiny cabbage, aconite and other relatively large weeds, at this time it is recommended to use herbicides, the control of grass effect is better, such as glufosinate-ammonium.

Although the effect of some herbicides is relatively good, they cannot be used on corn, or they cannot be used at certain stages, such as the following 3 types: quinoxalin, high-efficiency flupyroxalin, and glyphosate.

Since it takes 2-6 hours of absorption after post-emergence herbicide spraying in corn, in these 2-6 hours, whether the effect of the herbicide is good or not (that is, whether the weeding effect is ideal) is closely related to the temperature and air humidity.

Do not spray in the morning, noon or afternoon when the temperature is high and the weather is dry. Due to the high temperature, strong light, and fast volatilization of the liquid medicine, the liquid will evaporate after a while after spraying, so that the amount of herbicide entering the weed body is limited, and the absorption amount is obviously insufficient, which affects the weeding effect; At the same time, spraying pesticides in high temperature and drought makes corn seedlings also prone to pesticide damage.

The best spraying time is after six o'clock in the evening, because at this time spraying, the temperature is lower after application, the humidity is larger, the liquid medicine stays on the weed leaf surface for a longer time, the weeds can fully absorb the herbicide components, ensure the weeding effect, and the evening medication can also significantly improve the safety of corn seedlings, and it is not easy to cause pesticide damage.

It should be a herbicide about nicotine herbicide, the liquid will be slightly harmful to the heart leaves of corn, there will be yellowing, severe heart leaf curl, the roots become thicker, use brassinolide or 920 to beat 3 times in a row, once every 2 days, if there is no rain in these days, it is best to water the ground to increase the water circulation of crops.

I guess I used the wrong herbicide. If you are sure that it is used wrongly. Try the following remedies.

1. Quickly wash the leaf surface with clean water for many times, and at the same time pour enough water to promote the corn root system to absorb a large amount of water, so as to reduce the herbicide concentration in the plant and alleviate the pesticide damage.

2. Spray Yunda-120 (natural brassinolide) diluted 1500 times or gibberellin plus 1 urea aqueous solution or diluted 500 times with detoxification and foliar treasure, and spray the front and back of the leaves with a sprayer in the morning after the dew dries or in the evening to promote the normal growth of the plant and effectively reduce the pesticide damage.

3. The corn fields that have been damaged by pesticides should be combined with watering, and fast-acting fertilizers such as manure and urine of well-rotted people and animals, ammonium bicarbonate, ammonium nitrate, and urea should be applied to promote root development and regeneration, and restore the physiological function of the damaged corn, so as to reduce the damage of nicosulfuron pesticide damage to corn. At the same time, it is necessary to spray 1%-2% urea or potassium dihydrogen phosphate solution or 60-800 times of Huimanfeng liquid on the foliar surface, which is beneficial to the normal growth of corn.

If the corn has not been planted for a long time, calculate the growth cycle of the corn and it can mature before the frost, in order to ensure the harvest, it can only be replanted again.

Summary. Hello, it should be a herbicide, the liquid will hit the heart leaves of corn will have a slight damage, there will be yellowing, serious heart leaf curl, the roots become thicker.

After the herbicide is finished after the corn seedling, the leaves in the center of the seedling are yellow, and the corn is still growing normally, hello, it should be the herbicide, the liquid will hit the heart leaf of the corn will have a slight pesticide damage, there will be yellowing, serious heart leaf curl, and the root becomes thicker.

Hello, it is recommended to use brassinolide or 920 to hit 3 times in a row, once every 2 days, if there is no rain in these days, the most envious Hu is good to water the ground, increase the water circulation of the crop.

The heart leaves are not rolled, but the middle leaves are yellow, I have been on herbicide for 6 days, can I ease up.

Hello, it's okay to watch the leaves go green, if it has been yellowing, it is recommended to spray it with brassin.

Not rolling the leaves should be not harmful to the medicine.

The middle part is yellow, the pointed part of the leaf is green, and the lower part is yellow.

Hello, in this case, it will ease up in a few days, and you can just leave it alone. Spray herbicides and try to avoid the center of the plant.

1. Symptoms of pesticide damage (1) Nicosulfuron pesticide damages corn 3 5 days after spraying nicosulfuron, 5 10 days after spraying nicosulfuron, the corn heart leaves turn green, turn yellow, or irregular green spots appear on the leaves. Some leaves are curled into a cylindrical shape, the leaf margin is shrunken, and the heart leaf is oxtail-shaped, which cannot be extracted normally. Corn growth is inhibited, plants are dwarfed, and partial clumps, secondary stems may be produced.

If the pesticide damage is mild, it can resume normal growth, which will seriously affect the yield. (2) The pesticide damage of 2-methyl-4 sodium chloride salt is mainly manifested as leaf distortion, the heart leaf forms onion leaf-like curl, and presents abnormal elongation, the stem base is swollen, the aerial root can not grow, and the male panicle can not be extracted without manual peeling. The leaf color is dark green, and the plant is dwarf when it is severe, and the leaves turn yellow and dry; Fruit ears cannot be formed on the fruit position, so fruit ears often grow on the lower node position of the troubled plant; The lower internodes are fragile and easy to break, the root system is underdeveloped, the roots are short and small, and the lateral roots grow irregularly, which has a great impact on the yield and even the harvest is lost.

3) Acetochlor is a broad-spectrum and efficient selective herbicide for pre-emergence soil treatment, which is sprayed on the soil surface after sowing and before emergence. Poaceous weeds are absorbed by young shoots, broad-leaved weeds are absorbed by roots and young shoots, and the agents entering the body can interfere with nucleic acid metabolism and protein synthesis, so that young shoots and young roots stop growing and eventually die. It can last for about 2 months in the soil.

Amide herbicides can inhibit plant respiration and photosynthesis, inhibit the biosynthesis of proteins and RNA, and make plants unable to produce substances needed for life and die; This type of herbicide can only control the young shoots of grasses and weeds, but not the adult weeds. The field dosages of alachlor, metolachlor (Dur) and acetochlor were 120-144 grams, 72-144 grams and 25-50 grams of active ingredients per mu (667 square meters), respectively. When the dosage is too large, it will cause dwarf of corn plants; Some seeds cannot be unearthed, growth is inhibited, the leaves are deformed, the heart leaves are curled and cannot be stretched, sometimes whip-shaped, the rest of the leaves are shrunken, and the rhizome nodes are swollen. Heavy soil clay and cold wet blocks can promote the formation of pesticide damage.

4) Triazine herbicides are mainly harmed by affecting a series of physiological and biochemical processes in plants, so as to achieve the purpose of interfering with and inhibiting photosynthesis, so that weed seedlings can not carry out photosynthesis and are difficult to supplement essential organic nutrients and starve to death; This herbicide is effective in controlling annual gramineous weeds and broadleaf weeds in the field, and is relatively safe to use in corn fields. The main varieties that should be used by Wang Xing are atrazine (atrazine), grass jingjin, cyanochlorazine, etc.; The field dosage was 67-100 grams and 120-160 grams per mu (667 square meters), respectively. However, if the soil organic matter content is low (below the sandy soil or heavy rain after pre-seedling application, it can cause leaching pesticide damage.

The use of corn in the 5-leaf stage after seedling can also cause pesticide damage to corn under low temperature and rainy conditions. It is manifested as yellowing of corn leaves. Generally, the leaf color can turn green after 10-15 days and resume normal growth.

5) Paraquat herbicides are non-selective contact herbicides that kill the green group of all plants.

After the use of post-emergence herbicides in corn fields, yellowing and wilting appeared, indicating that herbicide damage occurred, mainly due to the following reasons:

1. The temperature is too high.

2. After the corn has 5 leaves in one heart, the liquid medicine is sprayed on the corn heart leaves.

3. Mixed use of herbicides and organophosphorus pesticides in corn fields.

Wait. Remedial measures: pay close attention to spraying liquid nitrogen fertilizer to stabilize the harvest + brassinolide + gibberellic acid, according to the recovery of corn, spray once every 3 days, and spray 3 times in a row to relieve the pesticide damage.