Silicone Auxiliaries and Precautions in The Use of Pesticides

Silicone builders are a class of silicone surfactants that are often used as spray aids for pesticides.Silicone builders are among Catalysts And Auxiliaries.Compared with other spray auxiliaries such as spray dried Polymeric Aluminium Chloride（It also can be used as a Flocculant）,silicone auxiliaries have the following remarkable features in addition to the ability to increase the wetting, spreading and adhesion of the liquid: First, the surface tension of the liquid can be lowered to a lower level. 20 mN/m or so; second, it can promote the absorption of liquid medicine through the pores; third, it has the function of resisting rain erosion. Therefore, it can effectively reduce the amount of pesticides used and the amount of spray, save the cost of pesticides and labor, and reduce the labor intensity. Therefore, it is well received by users and the use area in China is gradually expanding.

The reason why silicone additives produce phytotoxicity is that silicone additives can cause the stratum corneum of the leaf epidermis to "dissociate", so that its water retention capacity is reduced, cells are damaged, and eventually phytotoxicity is caused. The main phytotoxicity symptoms are plants. The leaves are chlorotic and dry, and abnormal brown sediment or halo is produced on the fruit trees, which seriously affects the yield or quality of the crop. The occurrence of silicone auxiliaries is closely related to the crop variety, the type of the agent, the concentration of the auxiliaries, the amount of the plant leaves, and the temperature at the time of application. The waxy layer of the leaves is thinner, and the crops that are easy to be wetted (such as cucumber, beans, etc.) are more susceptible to phytotoxicity than the thicker waxy layers of rice, ginger, and onion, and even different fruit varieties have phytotoxicity. The degree is also different; the addition of silicone additives in herbicides (such as chlorhexidine, nicosulfuron, flufenazone, etc.) has a higher risk of phytotoxicity than pesticides and fungicides, nevertheless, The addition of silicone additives when spraying insecticides and fungicides also has the phenomenon of phytotoxicity; the concentration of silicone additives used in crops susceptible to phytotoxicity or sprayed with medicinal pesticides High, the greater the risk of phytotoxicity; the greater the amount of drug in the leaves of the plant, the higher the temperature at which the drug is applied, the greater the risk of phytotoxicity.