Which herbicide is better to use in corn or wheat fields? How do I use it? What is the identification and remedy of herbicide damage?

Herbicide is a kind of substance that can make weeds die thoroughly or selectively, also known as herbicide, which is used to destroy or inhibit plant growth. Which herbicide is better to use in corn or wheat fields? How do I use it? What is the identification and remedy of herbicide damage?

Which herbicide is better to use in corn or wheat fields?

The effect of wheat herbicides depends not only on wheat herbicides, but also on other aspects such as spraying time, air temperature, weed resistance, dosage and so on. In addition, the best time to carry out chemical weeding in wheat field should be from mid-late November to early December, during which the resistance of wheat is the strongest, the sensitivity of weeds to herbicides is the strongest, and the weeding effect is the best. You can use:

1. Xiaopai-Chishijing-benzenesulfuron (wheat field herbicide) fluazosulfuron

2. Normandy-post-seedling herbicide in wheat field (high-end broadleaf double weeding type)

3. Yitao-a new herbicide in wheat field-Maijie

4. 10% benzenesulfuron (herbicide in wheat field)-wheat straw ban-Yuexiu

Corn is cultivated in all parts of our country. Corn likes high temperature and generally matures in summer and autumn. therefore, it is hot and rainy in summer and autumn, and weeds are common in corn fields. the main weeds are Magnolia mandshurica, barnyardgrass, Setaria angustifolia, amaranth, Portulaca oleracea, amaranth, aconite and so on. Corn is most seriously harmed by weeds at seedling stage, and chemical control saves time and effort, but there are a variety of herbicides in corn fields in the market, farmers often do not know how to choose, many farmers mistakenly choose the wrong herbicides, causing unnecessary damage to corn growth. Therefore, understanding the types and correct use of herbicides is the key to the control of summer maize weeds. Corn weeding can be used:

1. Amide herbicides: at present, these products are the most important herbicides in corn field, which can be absorbed by weed buds. Soil closure treatment before weed germination can effectively control annual Gramineae weeds and some annual broad-leaved weeds. There are many kinds of herbicides, such as Acetochlor, alachlor, butachlor, Metolachlor, Metolachlor and so on.

2. Triazobenzene herbicides: it can effectively control annual broad-leaf weeds and annual Gramineae weeds, mainly absorbed by weed roots and a small amount by weed stems and leaves. The representative varieties are atrazine, cyanazine, simazine, promethazine and so on, among which atrazine is widely used, which is safer to corn and has the highest activity, but atrazine should be mixed with Acetochlor to reduce the dosage and improve the herbicidal effect and safety to the following crops.

3. Phenoxy carboxylic acid herbicides: mainly used to control broad-leaved weeds and aconite after maize seedlings. The representative varieties are 2-methyl-4-chloro-sodium salt and 2.4-murine D-butyl ester. Among them, 2-methyl-4-chloro-sodium salt is widely used to control Cyperus roxburghii in corn field, but it is easy to cause drug damage if it is not used properly.

4. The mixture of nicosulfuron and atrazine is an ideal herbicide mixture, which can control not only many annual weeds, but also perennial Gramineae weeds and Cyperaceae weeds. However, it can not be mixed with organophosphorus pesticides before and after use, but can be mixed with pyrethroids insecticides.

5. The mixture of Acetochlor, atrazine and paraquat has both sterilization and herbicidal effect, and its application in maize growing period can effectively control many kinds of weeds in corn field. There are many similar products, and there are herbicide mixtures that use glyphosate instead of paraquat.

How do I use herbicide?

1. Strictly control the dosage. If the dose is too high, it will cause drug damage.

2. Strictly control the period of use. If the herbicide is not applied at the right time, the herbicide coincides with the sensitive period of the crop, which will cause drug damage. For example, the use of herbicide, butachlor and dichloroquinolinic acid during rice seed germination can easily reduce the emergence rate of rice seedlings, reduce the quality of seedlings, and die in serious cases. 2.4 the herbicides such as Mel D butyrofendil and other herbicides were sprayed before the third leaf stage and after jointing to the flowering stage of wheat, which would cause drug damage, make the leaves of wheat ears curl and affect heading.

3. Choose the correct method of pesticide application. If the method of application is improper, it will also cause drug damage. For example, when using oats in wheat fields, it is easy to cause drug damage due to the improper concentration of mixed soil, which is the same as the sowing concentration of wheat. Soil treatment agent used in post-seedling stem and leaf treatment, stem and leaf treatment agent used in soil treatment can not achieve the effect of weeding. Spraying herbicides requires an adequate amount of liquid spray, and generally do not use a low-volume fogging machine.

4. the application of pesticide should be uniform and thoughtful. Herbicides, whether sprayed or sprayed with soil or fertilizer, should be uniform. Uneven application of pesticide is easy to cause drug damage or poor weeding effect.

5. Master the appropriate interval of application. When two chemicals are used for the same crop. Should grasp the appropriate interval, the interval is too close will also produce drug damage. For example, the use of paspalum at the same time or soon, but also the use of organophosphorus or carbamate insecticides, so that rice loses the ability to detoxify paspalum, resulting in drug damage.

6. Pay attention to field management. The soil should be cultivated as smooth as possible, and the field operation, fertilizer and water management should be matched with the application of herbicides.

What is the identification and remedy of herbicide damage?

Most herbicides have strong selectivity, are very sensitive to crops, and have high residues. Coupled with the lack of knowledge of safe use by some farmers, the problem of herbicide damage is more common.

Herbicide damage can be divided into three types: acute type, chronic type and residual type. The acute type occurs quickly, the symptoms are obvious, and the drug damage occurs a few hours or days after application. The damaged leaves showed symptoms such as spots, anxiety, perforation, curling, deformity, wilting, yellowing, chlorosis or albinism. The chronic type has a long incubation period, and the symptoms of drug damage are not obvious, but the growth and development of crops are obviously hindered, and the yield and quality are decreased. The residual type means that the crops applied in the current season do not suffer from drug damage, while the residual chemicals in the soil cause drug damage to the next crop sensitive crops. Once drug damage occurs in production, remedial measures should be taken as soon as possible.

1. Rinse with clean water. When the stems and leaves of crops are damaged by herbicides, you can quickly use a clean sprayer to spray clean water on the damaged plants for two or three times to remove or reduce the chemicals on the crops. For herbicides that are prone to decomposition of alkaline substances, 0.2% quicklime or sodium carbonate can be added to the water, mixed evenly and sprayed, which has a good effect on removing and reducing the drug damage.

2. Attack both water and fertilizer. After the damaged plants were washed with clean water, they were irrigated with sufficient water as soon as possible, and both water and fertilizer were attacked. Sufficient water irrigation can not only satisfy the large amount of water absorption of roots and reduce the concentration of drugs in crops, but also effectively eliminate the residues of herbicides in soil. Combined with watering and topdressing, it can promote the rapid growth of crops and improve the drug resistance of plants. Foliar topdressing can be combined with water spray flushing, adding urea to the last flushed water to form 0.2% solution, or 0.3% potassium dihydrogen phosphate solution spraying, the effect is good.

3. Spraying plant growth regulators. Herbicide damage hinders the growth of crops, so plant growth regulators that promote their recovery can be sprayed immediately, such as gibberellin, Lufeng 95, etc., about 5 days after spraying, the crops will resume their growth and development. Pay attention to the strict dosage, spray the key parts of tender leaves and tender stem tips, so that they are evenly covered with liquid medicine.

4. Ploughing and loosening soil at the right time. Combined with water and fertilizer management, timely ploughing and loosening soil. The middle tillage was shallow at first and then deep, and it was ploughed for 2 to 3 times in a row. In order to enhance soil permeability, improve soil temperature, facilitate microbial activity, reduce drug damage, promote root absorption of water and fertilizer, and restore crop growth.

5. Replanting or replanting. If the herbicide damage is serious and the above remedial measures are expected to have little effect, they need to be replanted or replanted. When the season permits, the original crop can be replanted immediately; if the suitable period for replanting the original crop has passed, other suitable crops that are not sensitive to the herbicide should be replanted in time.