Do you know what the seven methods of identifying invalid pesticides are?

Do you know what the seven methods of identifying invalid pesticides are? In fact, there is no very good way to check outside the laboratory whether pesticides are not working, whether they are still killing pests and weeds, other than monitoring the results of pesticide use. However, the following methods for identifying ineffective pesticides can also help you to a certain extent.

1. Mix or shake pesticides and observe changes Many pesticide formulations are normal to have a certain degree of separation or agglomeration when they are placed, but excessive separation or agglomeration that cannot be remixed indicates that the pesticide product has deteriorated. If you suspect that the pesticide may have failed, mix a small amount of the pesticide in the jar and see how it mixes.

If it is a pesticide concentrate that could have been emulsified, it turns out that when water is added, sludge or mixture separates and does not form a normal milky white color, which means that the pesticide has lost its ability to form an emulsion.

If the wettable pesticide clumps and does not mix with water, the pesticide has failed.

If dust or particles clump and cannot be separated by shaking, the pesticide may not be too wet to work.

If it is a pesticide spray, you can observe whether the nozzle has been blocked by aerosols.

2. Pay attention to the odor changes of pesticides Some liquid pesticides can accumulate gases, which can break the container, or it may be dangerous when you open the container. The characteristic odor of some pesticides becomes more intense as they deteriorate. If you smell an unusually strong odor in the pesticide storage area, it could mean a pesticide leak or spill, and it could also indicate that the pesticide is deteriorating and failing.

3. Look at the shelf life of pesticidesIf the manufacturer of pesticides lists the shelf life of pesticides on the container, then you can judge whether it is still usable. If not, the shelf life of pesticides is generally about two years. Whether the pesticide is dried, liquid, concentrated, or ready-to-use, its shelf life will vary.

Dry powders, wettable powders, or granular pesticides are generally easier to store at low temperatures than liquids, but they break down more easily than liquids when exposed to heat, humidity, or sunlight. Pesticides containing low concentrations of active ingredients also generally lose their effectiveness more quickly than pesticides at higher concentrations. Certain inert components in products, such as stabilizers and emulsifiers, can also affect the degree to which pesticides become ineffective.

This method is, 1 to shake the pesticide, 2 to dilute with water, observe the dissolution, 3 taste, 4 color, 5 touch whether there is particle, 6 sun irradiation to see the degree of volatilization, 7 look at the shelf life, you can distinguish the invalid pesticide.

At this time, you can judge by the taste or style, if the pesticide has been agglomerate, it means that it has failed, and it can also be judged by shaking, if you want to change it, the pesticide has a particularly serious stratification situation, it is likely to be expired.

Identification is carried out by shaking to observe the odor, expiration date, production date, use, storage environment, and storage time of the pesticide.

1. Observation method: the powder pesticide is obviously lump or kneaded into a lump by hand, which is not easy to crush, indicating that the drug has long been ineffective and cannot be applied. The moisture content of powder pesticides is generally below 55%, and the lump is caused by storage for a long time and excessive moisture absorption, which dissolves the relevant ingredients.

If the emulsion pesticide finds that there is sedimentation and layered flocculation in the pesticide, the medicine bottle can be put into boiling water and left for 1 hour, if the precipitate is dissolved, the flocculent subsides, indicating that the pesticide is reasonable; Otherwise, it cannot be used.

2. Cautery method: This method is used to identify powder pesticides. Take 10 20 grams of powder pesticides, put them on the copper sheet and put them on the fire, if there is smoke, it is confirmed that the pesticide is not ineffective, otherwise it indicates that it has been ineffective, and this method is generally used to evaluate 5% of Duoyinling powder.

3. ** method: This method is used to identify emulsion pesticides. According to the characteristics of emulsion pesticides that are easy to stratify, first of all, whether they are stratified or not, if they are not stratified, it indicates that the pesticide is reasonable; If layered, it can fluctuate left and right many times, make it even, let it stand for 40 60 minutes, and then carefully observe, if it is layered again, it indicates that the pesticide is ineffective and can not be used.

4. Dissolution method: This method is used to identify the deposited emulsion pesticides. Soak the bottle in 40 60 water for 60 minutes.

If the sediment at the bottom of the bottle melts, it means that the pesticide is not ineffective. If the precipitate does not dissolve, the precipitate can be filtered out, take a small amount and fill with appropriate warm boiled water, if the precipitate is melted, indicating that the pesticide can still be used.

5. Water method: This method is used to distinguish powder, wettable powder and emulsion pesticides. If it is a powder, you can use 50 grams of medicine to put it into a glass teacup, add appropriate cold water, stir to dissolve it, and let it stand for 30 minutes.

The wettable powder is easy to form lumps when it is stored, so you can grind the lumps into powder form first, and add a little cold water. If it melts quickly, it indicates that the pesticide is reasonable, and vice versa.

In addition, the pesticide sample can be lightly sprinkled on the water surface, and the reasonable pesticide can be sunk into the water for 1 minute; If the water surface is not wet for a long time, it is an ineffective or ineffective pesticide. If it is an emulsion, you can put a small amount into a glass teacup, fill it with a small amount of water to mix, and let it stand for 30 minutes. If there are no oil beads on the water surface and no sediment in the cup, it indicates that the pesticide is reasonable.

The first is to smell the smell, if there is no strong smell, it will be invalid, and the second is to look at the shape, if there is a melting, it will gradually fail.

It depends on whether the pesticide is clumpy, or whether it is granular. You can also take some pesticides and burn them with fire, if there is white smoke, it means that the pesticide has not failed. You can also see whether the pesticide is layered, if there is no layering, it means that the pesticide has not failed.

Soak the pesticide in warm water for an hour, if there is sediment. It means that the pesticide has failed. You can also add pesticides to the water, and if these pesticides float on it, it means that the pesticide has not failed.

The pesticide can be dissolved in water to observe the sediment, the pesticide can be heated to smell the smell, the appearance of the pesticide can be observed, and the certificate and validity period of the pesticide can be observed.

At this time, it can be judged by the taste, and it can also be judged according to the state of the pesticide, according to the production date, or according to the appearance of the agent, and then it can also be judged according to the way of the first to determine whether the pesticide is layered.

Speaking of the word pesticide, everyone should be very familiar with the pesticide is a commonly used drug in the agricultural field, it is a chemical agent used to control pests and diseases and regulate plant growth. There are many types of pesticides, and the methods of use are similar, and they play a vital role in agricultural production. Any product will have a shelf life, then, of course, pesticides are no exception, and they will also face similar problems, such as failure problems.

Presumably, when farmers buy pesticides, they will have some considerations in their hearts, and they will think about whether the pesticide is pure or not, whether there is a failure problem, and only a good pure pesticide can play the role of pesticides when spraying. In this regard, we have the following methods to identify whether the pesticide is ineffective.

First of all, it is direct observation, if the characteristics of the pesticide are powdery, you can first observe whether there is obvious dampness and caking on the appearance, smell the smell of the medicine with your nose, if there is a caking phenomenon, and the smell is abnormal, it means that the pesticide is basically ineffective. For the emulsion type, you can first let the bottle stand to observe whether the liquid is stratified, if there is sediment or flocculent, it means that the pesticide has failed. Or shake the drug vigorously first, and then let it stand for observation, if there is still delamination, it means that the drug is ineffective.

Second, we can take a small part of the pesticide in an appropriate way and heat it on a metal sheet, and the normal pesticide will produce white smoke and a strong pungent odor. If there is no above phenomenon, it can also mean that the pesticide has failed. Third, for wettable powder pesticides, a small amount of pesticides can be weighed and put in water to observe the speed of their sedimentation and the solubility of the pesticides.

Whether pesticides play a good role will have a different effect on our crops, a good identification method can allow us to quickly and effectively identify good pesticides, alleviate the concerns in our hearts, and wish our farmers a good harvest every year.

I usually only judge by the production date, and if the date is over, it will definitely be invalid.

I know four ways to identify, the first is the intuitive method, for pesticides that have not been used, you can directly check their production date and shelf life, and observe whether the outer packaging is damaged, leakage and other abnormalities, so as to determine whether the pesticide is effective; The second is the heating method, this method is suitable for pharmaceutical pesticides, take an appropriate amount of pesticides and put them on a piece of metal for heating, if a large amount of white smoke comes out, and accompanied by a strong pungent smell, this indicates that the pesticide is effective; The third is the floating method, which is suitable for wettable powder pesticides. Take a cup of 200 grams of water first, then weigh 1 gram of pesticide, gently and evenly sprinkle it on the water surface and observe carefully, it is an effective pesticide that is moistened and can sink in water within 1 minute, otherwise it is an invalid pesticide; The fourth is the oscillation method, which is suitable for emulsion pesticides. For the pesticide with oil-water stratification, shake the agent vigorously first, stand for 1 hour and observe, if there is still delamination, it means that the pesticide has deteriorated and failed.

At this time, you can judge according to the production date, but also according to the state of the pesticide to judge, if the pesticide has a particularly serious agglomeration, it means that it has expired, and then you can also put the pesticide in the water, if there is a stratification situation, it means that it has expired.

When purchasing or using chemical pesticides, it is necessary to identify the quality of pesticides, if the purchase or use of pesticides that have failed, not only cause direct economic losses, but also easily cause pesticide damage, and at the same time, it will also lead to a reduction in yield due to the lack of timely and effective control of pests and diseases. Commonly used identification methods are:

For granular pesticides, first look at the appearance of the agent, if it has already obviously returned to moisture and clumps, the smell of the medicine is not strong or there is another smell, and you can use hand rubbing to participate in the group, indicating that it has been basically ineffective; For emulsion pesticides, let the medicine bottle stand first, if the liquid medicine is turbid or emerges into layers (i.e., oil-water separator), there is sediment or sediment suspension, indicating that the agent is likely to be ineffective.

The heating method is suitable for granular pesticides. Take 5 10 grams of pesticides, put them on a piece of copper and heat, if it causes a lot of smoke and has a strong unpleasant smell, it indicates that the agent is excellent, otherwise, it means that it has long been ineffective. The flotation method is suitable for wettable powder pesticides.

First take a cup of 200 grams of purified water, then weigh 1 gram of pesticides, gently, evenly sprinkle on the surface of the lake and observe carefully, in 1 minute wet and cold and can sink strong electrolytes is not ineffective pesticides, otherwise it is ineffective pesticides.

This method is suitable for wettable powder pesticides. Take 30 50 grams of pesticides, put them in glassware, first put a small amount of water to make it viscous, then add 150 200 grams of purified water and stir, and let it stand for 10 minutes to observe. Among them, the ineffective pesticides have good solubility, the suspended powder in the liquid is fine, the sedimentation rate is slow and the amount of deposition is small, and the ineffective pesticides are the opposite.

** Method applies to emulsion pesticides. For pesticides with water and oil layers, first use a strong medicine bottle and let it stand for 1 hour before observing. If there are still layers, it means that the agent has long been moldy and ineffective.

This method is suitable for emulsion pesticides. Put the pesticide with precipitate into warm boiled water (the temperature should not be too high, 50 60 is appropriate) and observe it after 1 hour. If the precipitate gradually melts, it indicates that the agent is not ineffective, and it can be reapplied after the precipitate is thawed; If the sediment is difficult to melt or does not melt, it means that it has long been ineffective and can no longer be used.

This method is suitable for emulsion pesticides. Take 50 grams of pesticides, put them in a glass bottle, put 150 grams of water, and let them stand for 30 minutes after exerting their strength. If the liquid medicine is a uniform milky white, it means that the agent is not ineffective, otherwise it is an ineffective pesticide, and the more oil bleaching on the top layer, the worse the efficacy.

Check if the product has passed the expiration date. The expiration date of pesticides is generally 2 years from the date of production of the product. If the expiration date is exceeded, the pesticide may deteriorate and become ineffective.

For products within the expiration date, it depends on the change in appearance characteristics. If the powdered pesticide is obviously damp and agglomerate, the smell is not strong or there are other peculiar smells, it indicates that it has become ineffective; Emulsion pesticides should be placed in the bottle for observation first. If the liquid is turbid or stratified, precipitated or flocculent suspended solids, it indicates that there is a high probability of reagent failure.

Remove a small amount of the milky insecticide and place it in a container of water.

After stirring, observe the dissolution. If it immediately turns into a milky white liquid, then it is a real insecticide. If there is oil-water separation or poor dissolution, it is a fake pesticide.

Put the emulsified pesticide precipitated in the bottle into hot water. After 1 hour, the ineffective pesticide precipitate dissolves slowly, while the ineffective pesticide precipitate does not. It is an effective control of crop diseases, insects and weeds.

Due to the toxicity characteristics of pesticides, people often talk about the color change of drugs, believing that pesticides are the main culprits of food safety and environmental pollution, and there are constant calls to resist the use of pesticides.

Integrated control is an effective and sustainable way to control diseases, insects, weeds and rodents, but in actual production, pesticides are still one of the most important control measures, so pesticides are an important means and tools to protect crops and reduce yield loss. The irrational use of pesticides will cause problems such as crop pesticide damage, human and animal poisoning, environmental pollution, and food safety. Especially in developing countries, there are still a large number of highly toxic pesticides, and farmers have low technical level and lack of necessary pesticide safety protection equipment.

Excessive pesticide residues not only affect the quality and safety of food, affect the health of consumers, but also affect the export of agricultural products, and even affect the development of the agricultural industry. Strawberry chips have had a significant impact on the production and sales of strawberries in China, affecting consumers and causing huge losses to farmers. Prevent and reduce the occurrence of pesticide risks.

It is necessary to vigorously popularize the technology of integrated pest control, reduce the use of pesticides, vigorously promote biological control technologies, including biological pesticides, strengthen technical training on the safe use of pesticides, and especially strictly implement the regulations on the use of pesticides.