How long does it take for the herbicide to take effect and how long does the herbicide work

Different kinds, different times. For example, "paraquat" wilts after a few hours; 7 days after "glyphosate"; There are also fiefdom drugs that form a medicinal layer on the surface of the soil, "Chlorazine" and "acetochlor", and the new grass buds are unearthed and effective.

1. Choose the right herbicide Because each herbicide has a certain herbicidal spectrum, which is incitiating and selective. Therefore, it is necessary to choose effective herbicides according to the types of crops and the main varieties of weeds. At the same time, herbicides should be selected according to the farming system.

In addition, it is important to pay attention to mixing and alternating herbicides. Because the continuous use of the same herbicide for many years can easily lead to the gradual decrease of susceptible weeds and the rise of resistant weeds, herbicides should be mixed and alternately used between years to achieve the purpose of long-term control of weeds.

2. Select the best period for application According to the nature of the herbicide, the occurrence period of weeds, the growth period of weeds and crops, and the appropriate period of drug use. There are many varieties of herbicides, including stem and leaf treatment agents, soil treatment agents, contact herbicides, biocidal herbicides, etc., some are suitable for pre-bud weeding, and some are suitable for stem and leaf weeding. Soil treatment involves spraying herbicides directly on the soil surface to kill newly germinated weeds.

For example, Doer, acetochlor, etc. should be used before the weeds are unearthed after the crop is sown, and the medicine should be used after the weeds emerge, which not only has a poor effect, but also harms the crop. Therefore, it is important to choose the best time to apply the herbicide.

3. The effect of herbicide is proportional to the temperature. When the temperature is high, the function of weeds in absorbing and transporting herbicides is strong, and the herbicide activity is also high, which is easy to give full play to the herbicidal effect in the action site of weeds. The test results show that when applying herbicides, the higher the temperature of air and soil, the more significant the efficacy, especially the herbicidal effect of stem and leaf treatment herbicides can be greatly improved, the use effect of herbicides in low temperature weather conditions will not only be significantly reduced, and the detoxification effect in crops will be relatively slow due to low temperature, so that it is easy to induce pesticide damage, and the temperature of herbicide application should be 20 35.

Air humidity also has a significant impact on the efficacy of herbicides, the application of stem and leaf herbicides in the case of relatively large air humidity can prolong the residence time of herbicides on the weed leaf surface, help the weed leaf surface stomata to open, thereby absorbing a large number of herbicides, to achieve the purpose of improving the weeding effect, after the herbicide is absorbed, it will be transported upward with a large amount of water, which is conducive to inhibiting photosynthesis and can significantly improve the weeding efficacy. Therefore, when using herbicides, the higher the humidity of the air, the more obvious the weeding effect; Otherwise, the weeding effect will be reduced.

Summary. In this case, different herbicides have different effective times. There is no set time, it can range from a few hours to a few days.

You can take a look at the instructions for the use of herbicides, which are usually mentioned. Glyphosate: generally takes 7 to 9 days to take effect, and about 15 days to die; Glufosinate-ammonium:

Generally, it is effective in 3 to 5 days, and 7 to 10 days to die. Paraquat: This herbicide for stems and leaves, which generally works quickly, begins to discolor after about 2-3 hours after application, and the paraquat herbicide is sprayed 7 to 10 days after quinoxalin

After application, the weeds stop growing within 2 days, about 5-7 days after application, the young leaves and primary tissues on the nodes become withered, and the plants die within 14 days.

In this case, different herbicides have different effective times. There is no set time, it can range from a few hours to a few days. You can take a look at the instructions for the use of herbicides, which are generally mentioned.

Glyphosate: generally takes 7 to 9 days to take effect, and about 15 days to die; Glufosinate-ammonium: generally effective in 3 to 5 days, 7 to 10 days of dead grass.

Paraquat: This herbicide for stems and leaves, generally works quickly, after application, about 2-3 hours after the weeds begin to be damaged and discolored, paraquat herbicide in 7 to 10 days after spraying: after application, the weeds stop growing within 2 days, about 5-7 days after application, the young leaves and primary tissues on the nodes become withered and the skin is searched, and the plants die within 14 days.

How long is the residual period of the herbicide and when can it be inserted.

About 30 days of wild herbicides are generally pre-emergence herbicides, it is biocidal, which contains grass to make reifin glyphosate, the effect is long-lasting, generally about 20 days, it is recommended to use pure notice after this kind of herbicide try to avoid the effective period before sowing, or spray a certain amount of Naian herbicide safety additives before sowing to prevent the problem of pesticide damage caused by residues.

Not detailed, so-so.

Rice planting should be planted 30 days later.

1. Pay attention to the prescribed ratio of herbicides. Any herbicide has the most suitable concentration for its object, and the use of the specified concentration can effectively kill weeds, otherwise it will not only fail to achieve the purpose of weeding, but will harm crops. 2 Pay attention to the time of spraying.

Do not spray in the morning when there is dew, because when there is dew on the crops, the herbicide may roll down with the dew or evaporate with the dew, which will reduce the effectiveness of the pesticide and will not serve the purpose of weedicide. It is also not possible to spray at noon on a sunny day, because the temperature is high at noon on a sunny day, and the crops close the stomata in order to avoid the rapid evaporation of water, so that the effective part of the herbicide is difficult to enter the crop and cannot have the effect of weeding. The best time to spray is before 10 a.m. on a sunny day and after 16 p.m., and spraying can be done all day on cloudy days.

In addition, if it rains within 6 to 10 hours after spraying, it should be re-sprayed after the weather is clear. 3 When using medicine, it should also be noted that some herbicides act on weeds and crops at the same time, and when using these herbicides, spray the liquid medicine directly on the weeds to avoid spraying the liquid medicine on the green leaves of crops and causing crop damage.

Hello answer, I have seen your question, and I am sorting out the answer, please wait for a while 1. Spring Festival and summer sowing crops, such as corn, soybeans, peanuts, etc., this kind of crops, when playing herbicides, can be in the morning and afternoon, due to the high temperature during the day during this period, especially at noon, more than 30 degrees of weather, not suitable for herbicides, the liquid evaporation is too fast, affecting the efficacy, you can choose between 7-9 o'clock, 16-19 o'clock, too early or too late, Take into account the dew.

2. If it is a crop sown in autumn or winter, such as wheat, when playing herbicides, it is necessary to choose a time close to noon, and the opposite of the above, choose between 10-15 o'clock for spraying, because the temperature is too low, the effect of the drug is also affected, choose this time period, the temperature has risen, the weeds are relatively well absorbed, and the weeding effect is relatively up.

The best time to spray herbicides is before 10 a.m. or after 4 p.m. on sunny days, and all day on cloudy days.

If it is a crop sown in the Spring Festival and summer, when the herbicide is played, it can be done in the morning and afternoon, due to the high temperature during the day during this period, especially at noon, the weather of more than 30 degrees, it is not suitable to play herbicides, and the liquid evaporates too quickly, affecting the efficacy, you can choose between 7 and 9 o'clock, 16 and 19 o'clock, too early or too late.

If it is a crop sown in autumn or winter, when playing herbicides, it is necessary to choose a time close to noon, and the opposite of the above, choose between 10 and 15 o'clock for spraying, because the temperature is too low, the effect of the drug is also affected, choose this time period, the temperature has risen, the weeds are relatively well absorbed, and the weeding effect is relatively up.

Precautions for herbicide use:

1. Pay attention to the selectivity, specificity and timing of chemical herbicides.

2. Strictly control the limited dose. Use in strict accordance with the dosage range, concentration and dosage specified in the drug instructions. Wanton Jane.

3. Rational mixing of pharmaceutical agents. When two or more herbicides are mixed, it is necessary to strictly grasp the proportion of compounding, application time and spraying technology, and consider whether there is resistance or other effects between each other.

4. Pay attention to the pesticide isolation and wind direction, the fog droplets are not too fine, so as not to cause pesticide damage to the adjacent farmland caused by drifting, and pay attention to the impact on the next crop.

5. Master the best time and technical operation essentials for herbicide application.

6. Pay attention to the influence of environmental conditions on herbicides, such as temperature, moisture, light, soil type, organic matter content, soil tillage and land preparation level, and other disturbance factors.

Summary. Hello dear, insecticides can only be used after 7 days of weeding, herbicides are weedicides, insecticides are insecticides, each in its own way. Generally speaking, bugs are small and easy to find, so it's good to use medicine.

7 days before and after spraying herbicides, it is strictly forbidden to spray organophosphorus insecticides, otherwise pesticide damage is easy to occur.

Dear, hello, weeding can only be used after 7 days of insecticide, the herbicide is weeding, the insecticide is insecticide, each in its own way. Generally speaking, bugs are small and easy to find, so it's good to use medicine. 7 days before and after spraying herbicides, it is strictly forbidden to spray organophosphorus insecticides and cherry trees, otherwise pesticide damage is easy to occur.

Spine caution. How long is the interval between the herbicide that specializes in lara seedlings and the ** that specializes in red spiders and rice bugs.

Hello, dear, more than a week.

Isn't it okay to have herbicides and pesticides two days apart?

Hello dear, preferably a week later, the time is too short and something will happen.

Different kinds, different times. For example, "paraquat" wilts after a few hours; 7 days after "glyphosate"; There are also fiefdom drugs that form a layer of medicine on the soil surface, "Qujin" and "acetochlor", and the new grass buds are unearthed and effective.

the duration of common herbicides in soil;

1. High-efficiency flupyrimethoxalin: its half-life in the soil is about 20 hours, which is easy to decompose pesticides in the soil, so theoretically after gramineous weed poisoning wilting and death (7 days) in planting corn is not very significant, but it is still recommended to plant broad-leaved crops the safest.

2. Quinoxalin: the half-life of digestion and digestion in soil is within one day, mainly microbial digestion, and the digestion speed is fast, and the half-life of digestion in the buffer solution of pH9 is 19 hours, and the half-life of digestion in sesame soil and sesame plants is days and days respectively.

3. Pyrethoxalen: It is rapidly hydrolyzed in moist soil, and the half-life of digestion is less than 7 days, and theoretically the half-life of photolysis and digestion in aqueous solution is 6 days.

4. Cyanfluoxate: the half-life of digestion in soil is less than 4 hours, and it will not cause toxicity to fish.

5. Alkyne oxalic acid: the half-life of hydrolysis and digestion is hours when the pH value is 9, and 64 hours when the pH value is 7, which is stable in acidic media.

6. Fineoxazole: The half-life of digestion in soil is 1-10 days.

7. Ethylcarboxyfluorfen: the soil is rapidly decomposed due to the action of microorganisms, and the half-life of digestion is about 11 hours, but according to the different types of soil digestion speed, under the same conditions, the digestion rate is yellow soil, black soil, red soil, so in the yellow soil area of North China, ethylcarboxyfluorfen can be used for 2 days before planting other crops;

8. Sulfafen: The half-life of digestion is 3 weeks in irrigated soil and 6-12 months in laboratory atmospheric soil, so in the plots where the agent has been used, in addition to soybeans, red beans and mung beans, it is necessary to plant other crops at least 12 months apart to be relatively safe for crops.

9. Ethoxyfluorfen: slow digestion in soil, with a half-life of 30 days, and finally decomposed into carbon dioxide by microorganisms in the soil.

10. Trifluorocarboxygrass ether: the half-life of soil digestion is 30-60 days, and 110 days under light conditions. After different herbicides are applied, the effect will appear at different times.

Herbicides such as glyphosate and paraquat generally take effect very quickly, in about a day. Herbicides such as herbicides such as herbicides need three to five days to be effective. The post-emergence herbicide in the corn field generally has an effect in 4-7 days, and the final effect takes half a month.

Is the herbicide applied in the morning or in the afternoon? In fact, there is no fixed statement, these two time periods can be considered, but for different people, there are still quite a few differences in the efficacy. Therefore, choosing the right time to weed can also be twice the result with half the effort.

The following is a brief introduction to the timing of herbicide spraying.

Spring spraying

Time should still be selected according to the season, for example, in spring and autumn weeding, it is dark early in the afternoon and the weather temperature is low, in this case, it is best to choose to spray herbicides at about 10 o'clock in the morning, at this time the dew in the field is basically gone, and it is also conducive to the absorption and utilization of herbicides after herbicide spraying.

Summer spraying

In summer, the temperature is higher, and the morning is relatively early, basically the dew is basically dry at 9 o'clock in the morning, and the dew gradually starts at 7 o'clock in the afternoon, so it can be said that spraying herbicides at 9 o'clock in the morning and four or five o'clock in the afternoon are good choices. From the perspective of safety, it is basically very hot at 9 o'clock in the morning in summer, and the transpiration effect is relatively large, so if the safety of the herbicide itself cannot be fully guaranteed, it is more recommended to spray in the afternoon.

Temperature factor

The temperature also has a great impact on the efficacy of herbicides, and the temperature also directly determines the time selection of spraying. In summer, the temperature is generally high, and the transpiration effect is relatively large, so in order to avoid water loss, crops will exert their physiological regulation ability, and will close the stomata. In this way, after spraying herbicides, it is difficult for the drug to enter the plant to exert its effect.

For example, if you spray in the morning, the temperature will gradually rise, and the temperature like this will reach more than 30 degrees Celsius by 11 a.m., and the stomata will be closed when the slope is exposed to high temperatures.

There is no such problem in the afternoon spraying, the temperature will gradually drop after four o'clock in the afternoon, the stomata will gradually open, after spraying herbicides, the drug is relatively easy to penetrate into the plant tissue, and the metabolic effect of the plant at this time is also relatively strong, and the effect of the drug is quickly exerted.

In addition to the factors mentioned above, if a little urea is added to the herbicide spray or if the field is fertilized before the herbicide is sprayed, the herbicide spray will also be more effective after spraying. In the problem of herbicide application, there is no best, only better, and mastering the appropriate application time and method will make you get twice the result with half the effort.