Judging pesticide deterioration and pesticide preservation
In the process of storage and use of pesticides, if the method is not appropriate, it may deteriorate and become invalid. Understanding the causes of pesticide deterioration and taking measures to solve them can prolong the effective use time of pesticides and improve the control effect. So, how to judge that the pesticide has deteriorated? How to store pesticides? Let's take a look together below.
1. How to judge that pesticides have deteriorated
Heat fusion method: Put the emulsion pesticide with the precipitate into the warm water of 50℃ together with the bottle. After 1 hour, if the precipitate slowly dissolves, it indicates that the drug has not expired. If the precipitate is difficult to dissolve or does not dissolve, the medicine has deteriorated and is ineffective.
Oscillation method: When oil-water separation occurs in emulsion pesticides, vigorously shake the bottle, and after standing for 1 hour, if a separation layer still appears, it means that the medicine has expired.
Floating method: Take 1g of wettable powder pesticide and sprinkle it evenly on the surface of 200ml of clear water. If it wets and sinks into the water within 1 minute, it is a non-expired pesticide, otherwise, it is an invalid pesticide.
Dilution method: Take 100g of emulsion pesticide, put it into a glass bottle and add 300g of water. Shake vigorously and let it stand for half an hour. If the concentration of the drug solution is uneven, there is emulsifiable concentrate on the top and sediment on the bottom, it indicates that the drug has failed. The more emulsifiable concentrates, the worse the medicinal properties.
Suspension method: Take 50g of wettable powder pesticide, put it in a glass container, add water and stir evenly. After standing for 10 minutes, if the pesticide has poor solubility and the suspended powder is coarse, it is an invalid pesticide.
2. How to store pesticides
Prevent sun exposure. Pesticides in brown bottles generally need to be stored away from light. Pesticides that need to be kept away from light, if exposed to light for a long time, will cause the pesticides to decompose and become invalid. For example, after being exposed to the sun, emulsion pesticides have poor emulsifying properties and reduced efficacy. Therefore, it is necessary to avoid sunlight during storage; when the microbial active preparation is irradiated with strong light, the active bacteria will lose their activity.
The temperature of the place where pesticides are stored should not exceed 25°C, and more attention should be paid to keep away from sources of ignition to prevent the decomposition of the pesticides; the preservation of pesticides derived from microorganisms requires special attention. Pay attention to anti-freezing at low temperature, and keep the temperature above 1℃; the common method of anti-freezing is to cover with chopped firewood, chaff or unused cotton quilt.
Pesticides with strong volatility should be sealed to avoid volatilization which reduces the efficacy, pollutes the environment and endangers human health. A small amount of pesticides that have expired or remain are not allowed to be dumped on the field, let alone poured into ponds, creeks, rivers or wells; nor can they be used after increasing the concentration at will. They should be buried deeply to avoid environmental pollution.
Pesticides should be stored in one place and marked. If the bottled pesticide is broken, the package should be replaced and a label should be attached to prevent misuse.
Pesticides cannot be stored in the same room as grains, oils, beans, seeds, vegetables, food, and animal feed. Take special care not to place them where children can reach.
Powder pesticides should be placed in a dry place to prevent damp and agglomeration and failure.
Classified storage. According to pH, pesticides can be divided into three categories: acidic, alkaline, and neutral. These three types of pesticides should be stored separately and not too close to prevent the pesticides from deteriorating; and they cannot be stored together with alkaline substances, ammonium bicarbonate, ammonium nitrate, etc. at the same time.
Do not store pesticides with flammable and explosive materials, such as fumigants, gasoline, etc., to prevent fires.
Next: No content.