Nowadays, many people like to use herbicides, how to reduce the harm of herbicides to crops?

The manual spraying equipment is backward and the spraying is uneven. Choose a printhead with good material, sturdy and high pressure. It is recommended to use a fan-shaped nozzle.

Before spraying, measure the spray flow and walking speed, determine the spray width, accurately calculate the spray amount and dosage, spray pressure, spray head on the ground to determine the height and walking speed, etc. The use of insecticides and fungicides is temporarily incorrect, which will affect the prevention effect. Improper use of herbicides is about the safety of crop growth.

Crops have different susceptibility to pesticides and fungicides at different growth and development stages, and their sensitivity to herbicides is also even different. Under normal circumstances, crops are particularly sensitive to herbicides at germination, pre-clover, and two-flower enema stages, which are prone to fatigue.

Pre-emergence herbicides can only be absorbed through the radicle, bud fossa or hypocotyl of weeds to kill weeds, and weeds are used after germination, and generally have no weeding effect or low weeding effect. Post-emergence weeding should also be used at a certain growth stage of a weed or crop to be safe and effective. The suitability of herbicide use depends on factors such as crop type, soil texture, climatic conditions, and drug method.

When using high concentrations of herbicides, sprays should never be re-sprayed. Otherwise, the concentration of local medication is too high, which is easy to cause local drug loss. After sowing, pre-emergence soil treatment is a method of spraying herbicides on the soil surface after sowing and before the crops have germinated.

This is how most soil treatment agents are used. Stem and leaf treatment herbicides usually lose their herbicidal activity by being deactivated or decomposed by microorganisms soon after falling into the soil, while soil treatment herbicides are generally ineffective against weeds after germination. Therefore, when using, it is necessary to choose the application method according to the characteristics of the herbicide, so as to give full play to its effect and avoid negative effects.

Before the crop is planted, the soil can be treated in front of the seedbed and can also be sprayed after the seedbed. Pusht, light extinguishing order, and atrazine should use Myogo early spray to reduce the amount of use and reduce residues. After germination, an accelerant or synergist is added to improve the efficacy and reduce the dosage.

Pre-emergence herbicides can only be absorbed through the radicle, bud fossa or hypocotyl of weeds to kill weeds, and weeds are used after germination, and generally have no weeding effect or low weeding effect. Post-emergence weeding should also be used at a certain growth stage of a weed or crop to be safe and effective.

Generally, it should be sprayed in sunny or breezy weather with a temperature of 20°C or 30°C.

When spraying, the direction of the nozzle hole should be consistent with the wind direction, and the direction should be perpendicular to the wind direction or the angle should not be less than 45°, and the downwind should be sprayed first, and then the upwind should be sprayed to prevent the liquid from drifting with the wind and injuring nearby sensitive crops.

Rinse with clean water. If the herbicide is oversprayed or the leaves of adjacent sensitive crops are damaged, clean water can be sprayed several times in succession on the affected leaves to remove or reduce pesticide residues on the leaves. For the pesticide damage caused by herbicides that are easy to decompose and fail alkaline substances, quicklime water or alkaline surface (sodium carbonate) solution can also be added to the water for leaching.

1. Spray water to rinse. If the herbicide is sprayed excessively or the leaves of adjacent sensitive crops are damaged, clean water can be sprayed on the affected leaves several times in a row to remove or reduce pesticide residues on the leaves. For the pesticide damage caused by herbicides that are easy to decompose and fail alkaline substances, quicklime water or alkaline surface (sodium carbonate) solution added to the water can also be rinsed.

2. Sufficient watering to increase the moisture of crop cells, reduce the relative content and concentration of drugs in the plant, and achieve alleviation and prevention effects; For pesticide damage caused by excessive soil application, irrigation and drainage can be used to wash the field to eliminate drugs and reduce pesticide damage.

3. Removal of drug-damaged organs. For serious local drug damage, the branches, leaves or fruits that have been severely damaged by the drug can be removed to avoid conduction.

The recommended dosage of each herbicide is the result of many years of practice and various experiments, and the dose cannot be arbitrarily increased or decreased to ensure the effectiveness of the herbicide and prevent the appearance of weak efficacy. Otherwise, a safe weeding system may also be weakened. Seedling pretreatment after sowing, also known as bud pretreatment, refers to the use of herbicides after sowing and before germination of crop seeds.

This period is relatively short, so it only takes a few days, and it is necessary to strictly control and use herbicides before the emergence according to the situation. After sowing, pre-seedling soil treatment is more effective in controlling weeds, but if the drug is not applied in time, it may germinate and become fragile. Temperature is an important factor affecting weed growth and herbicide efficacy.

In general, high temperatures help to exert the efficacy of herbicides, and herbicides are also very effective.

Soil properties have a great impact on the efficacy of herbicides, the soil block structure with high organic matter content is good, the adsorption capacity of herbicides is large, the number of soil microorganisms is large, the activity is vigorous, the herbicides are easy to decompose, the same dose is safe for crops, but the weeding effect is weak, so it is necessary to increase the amount of use appropriately. The bigger the weed, the stronger the resistance under normal circumstances, so apply herbicide when the weed is small and don't fight when it is large. Weeds are also in the seedling stage, and the effect is better.

On the contrary, when the crop reaches the middle and late stages, the spraying herbicide is easy to weaken, and the spray of the crop will make the leaves cover the weeds, and the weeds will be exposed to too little herbicide solution, which will affect the weeding effect. Crops absorb less liquid medicine and cannot achieve the purpose of weeding. On the contrary, if the moisture is good, the pores of the leaves will open, so spraying herbicides will be more effective.

The plots on which the soil treatment is carried out must be leveled and the rake is sprayed evenly. Otherwise, the effectiveness of the drug will decrease. The weeding effect of soil treatment and the order of weak sand, loam, clay on crops are reduced.

Therefore, the amount of sand should be moderately reduced, and the use of cohesive land should be moderately increased. After sowing, those who apply the pesticide before the seedlings cannot wait until the seedlings to apply it, and the chemicals suitable for soil treatment cannot be used as stem and leaf treatments casually. If Le Ling is a soil treatment agent, it cannot be used as a stem and leaf treatment.

Herbicides should not be sprayed in high temperature, high humidity and strong winds to prevent crops from weakening or decreasing their efficacy. In general, to spray herbicides, it is best to choose a sunny and windless day with a temperature of 10 30. In the middle of summer, the weeds grow fast due to high temperature and rain, which is an important period for weed control all year round.

At this time, if the weeds are not removed in time, the weeds will bloom and bear fruit, which will bring greater difficulties to weed control in the fall and next year.

It can not be sprayed when there is wind, it can not be sprayed on crops, it is necessary to pay attention to the time of spraying, to pay attention to the concentration of the drug, to pay attention to the frequency of spraying, so that the correct use of medicine can make it play a good weeding effect.

Don't spray when it's windy, and don't spray on crops. Pay attention to the spraying time, drug concentration and spraying frequency so that the correct medication can be used so that it can play a good weeding effect.

Different herbicides need to pay attention to different places, and finally look at the instructions on the herbicide you purchased.

It is best to wear thicker and wrap it tightly when spraying, if the herbicide is on the body, it will be really uncomfortable for several days, and you should take a shower and wash your clothes as soon as you finish it.

It works, but the effect on crops is not very large, and generally the herbicide can only fully exert its effective effect two to three hours after spraying.

Herbicides are chemicals that kill weeds or harmful plants without affecting the normal growth of crops. It can be used to control weeds in farmland or kill weeds or shrubs on non-agricultural land.

According to its action characteristics, it can be divided into selective herbicides and biocidal herbicides, selective herbicides refer to the use of a certain dose and concentration range, can selectively kill some kinds of plants, and other kinds of plants are harmless.

Herbicides are not harmful to crops, because if he is harmful to crops, this product will not be produced, and now the herbicide of Fujin pants is relatively mild, and there is no great harm to crops, but people can not take it.

Herbicides have the potential to affect crops.

In general, grasses weed herbicides have no effect on broadleaf crops, and broadleaf weed herbicides have no effect on grasses.

Precautions for using herbicides:

1. Herbicides should be prepared and used in strict accordance with the prescribed dosage, method and appropriate period.

1) The sown bush can not wait until the seedling is applied before the seedling, and the agent suitable for soil treatment cannot be used as a stem and leaf treatment. For example, fluoralin is a soil treatment agent and cannot be used as a stem and leaf treatment.

2) The medication should be appropriate. The application of herbicides during the sensitive period of crops is easy to cause pesticide damage to crops. For example, the herbicide use period in wheat field is from 4 leaf stage to jointing stage.

3) When treating stems and leaves, spraying at the 2nd to 6th leaf stage of weeds has the best effect.

2 Pay attention to the direction of the wind.

When spraying herbicides, the direction of the spray hole should be consistent with the wind direction, and the direction should be perpendicular to the wind direction or the central angle should not be less than 45 degrees, and the wind head should be sprayed first, and then the wind head should be sprayed to prevent the liquid medicine from drifting with the wind and harming the nearby sensitive crops.

3 Pay attention to weather conditions.

Herbicides should not be sprayed in high temperature, high humidity or windy weather to prevent pesticide damage to crops or reduce their efficacy. Generally speaking, herbicide spraying should be carried out in sunny and windless weather with a temperature of 10 to 30 °C.

4 Soil treatment.

The plot of soil treatment must be raked finely and evenly sprayed, otherwise the efficacy of the drug will be reduced.

5 Choice of Potions.

Chemical control of perennial weeds, to increase the dosage, some contact herbicides are ineffective against perennial weeds, should pay attention to the selection of use.

6. Appliance cleaning.

The sprayer for spraying herbicides must be thoroughly cleaned before spraying other drugs to prevent pesticide damage to crops.

Herbicides have a certain amount of damage to crops, and they will cause great harm in the process of use. In general, herbicides have some effect on plants, pathogens, soil microorganisms, and the environment. And it will not only cause environmental pollution, but also indirectly cause harm to the human body.

Next, let me explain to you in detail what are the specific hazards of crops.

First, the harm of herbicides to the soil.

When the herbicide is sprayed on the field, the herbicide components that are not absorbed by the weeds are free to exist in the soil. Most of the chemical herbicides currently used are long-residue types, and the residue period in the soil can generally reach more than 36 months. According to surveys, 20% to 70% of herbicides commonly used in production will remain in the soil for a long time, contaminating soil, groundwater and food.

The quality of the soil is declining, and the "cancer" of the land is what people call a "cancer field". In Northeast China, Heilong, Lijiang, Jilin and other places, due to the long-term overuse of herbicides, a large area of "cancer fields" has emerged.

Second, the toxicity of technology to plant harm.

This technical phytotoxicity is mostly caused by improper use or selection of application doses, application periods, herbicide mixing, application equipment, etc. , Shirts.

Third, residual phytotoxicity.

Long-acting herbicides can be phytotoxic to the next crop during crop rotation and land transfer.

Third, drifting drug damage.

Some herbicides are highly drifting. When applied to a particular crop, they can easily drift onto neighboring crops, causing the phytotoxicity of drifting.

There is no impact. The herbicide itself is used to remove weeds. There is no chemical reaction between it and the concentration. Therefore, it has no effect on the poor crops, but it can remove the weeds in the corresponding fields.

What are the favorite herbicides used by farmers? For the control of reed grass and wild thatch in the field of broad-leaved crops, concentrate alcohol + allyl ketone + chromogenic agent formula can be used to spray once and spray again immediately after the leaves are dry to achieve the best control effect. In the field of prevention and control of gramineous weeds, corn, and other gramineous crops in the field of wheat sowing, dogtail, weeds and wild oats and other gramineous weeds, tobacco can choose bicycle + atrazine formula, the safety level and low effect is very good.

In the control of grasses and semi-tolerant weeds, such as purslane, quinoa, diphyllum chinensis, schisandra chinensis, wild oats and other weeds, nicosulfuron + atrazine + atrazine formula can be selected, nicosulfuron + atrazine formula is a mixed preparation of the two, which can effectively improve the control effect of nicosulfuron and improve the efficiency of nicosulfuron. In the prevention and control of potato underground pests, such as potato underground pests are diverse, comprehensive control should be adopted in the prevention and control. For example, in the early stage of potato underground pest damage, chlorpyrifos, chlorpyrifos + nicosulfuron + atrazine can be selected, which not only controls the pests, but also achieves good results.

In the prevention and control of field pests of nightshade crops, chlorpyrifos, chlorpyrifos + nematicides can be selected, which is not only safe and effective, but also low in price. In the control of tomatoes, peppers, citrus, apples, peaches, pears, grapes, melons and other crops in the field, if the degree of pest damage is light, nicosulfuron, paraquat + atrazine can be used. For example, at the beginning of weeds or early sowing, then we can choose nicosulfuron + atrazine.

Although some herbicides have special effects on weeds, the use of thistles in the fields of crop safety, prevention and control is also considered The herbicide dichloropyridic acid has a residual time of 18 months, and the Solanaceae of Asteraceae and leguminous crops are particularly sensitive, so everyone is using it, and adverse drug reactions and residues must be taken into account. This is the end of this issue, thank you for reading the article, you can pay attention.