The chemical properties and structures of pesticide active ingredients are the basis of their biological activities. In general, chemical changes should not be allowed to occur in the effective components when mixed, so as to avoid affecting the decomposition and failure of the effective components. Organophosphorus and carbamate pesticides are sensitive to alkalinity. Pyrethroids and dithiocarbamate fungicides also decompose under strong alkaline conditions. Pay attention to the instructions for the use of pesticides. For example, the first pesticide description stipulates that alkaline pesticides cannot be mixed, then other mixed pesticides cannot be prepared if they are alkaline pesticides. In the same way, if the description of the first pesticide stipulates that acid pesticides cannot be mixed, then other pesticides participating in the mixture cannot be prepared if they are acid pesticides.

1. No more than 4 kinds of pesticides should be mixed

Generally, 2 ~ 3 kinds of pesticides are suitable for mixed use, and 4 kinds can be used if necessary. If there are more than 4 kinds of pesticides, adverse consequences will be easily caused.

2. The dosage of CO prevention drugs should be reduced

Due to the same goal of common prevention, it is necessary to cooperate with each other in drug strength, and the method of preparation is usually based on the rule of equal division and additive action. That is to say, when they are mixed, they should keep half of the original dosage respectively; when they are mixed with three drugs, the same should be done.

3. Different dosage forms are mixed in order

The mixture of pesticides should follow the sequence of micro fertilizer, wettable powder, colloidal suspension, water agent and emulsifiable concentrate, and stir continuously. After one agent is fully dissolved, the next is added. The two kinds of wettable powder should be mixed evenly, and then diluted with water.

4. Single treatment pesticides are mixed according to "each quantity"

At the same time, the "various quantities" of different targets are also frequently used in pesticide mixing. According to the mixed growth of diseases, insect pests and weeds in the same period, the target of concurrent treatment was confirmed, and the mixed drug control was selected. Due to the respective objectives of each control, it is necessary to maintain their respective effective control dosage (i.e. "each amount").

5. Mixed drug use

Mixed pesticides should be prepared and used as soon as possible, and should not be stored. The longer the storage time, on the one hand, the efficacy is easy to reduce, on the other hand, it will produce adverse reactions.

6. Add water first and then add medicine

For the two dilution mix, add half a bucket of water into the sprayer and mix with the first pesticide. Then, pour another pesticide into a plastic bottle and dilute it with water. After dilution, pour it into the sprayer and stir it evenly and so on.