Insecticides

Introduction

Insecticides refer to a type of insecticide that kills pests, mainly used to control agricultural pests and urban health pests. Such as beetles, flies, grubs, noseworms, fleas, and nearly 10000 other pests. Insecticides have a long history of use, large amounts, and a wide variety.

Classification

There are many classification standards for pesticides. Today, we will learn about pesticides from the aspects of mode of action and toxicology.

According to the mode of action, pesticides can be classified as:

① Stomach poison. It enters the digestive system through the mouth of the insect and has a toxic effect, such as Metrifonate.

② Contact killing agents. After contact with the epidermis or appendages, it penetrates into the insect body, or corrodes the wax layer of the insect body, or blocks the valve to kill pests, such as pyrethrin, mineral oil emulsion, etc.

③ Fumigant. Vapor is generated by volatilization of toxic gas, liquid or solid to poison pests or germs, such as Bromomethane.

④ Inhalation of insecticides. Absorbed by plant seeds, roots, stems, and leaves and transported to the entire plant, within a certain period of time, the pathogen or its activated metabolites enter the insect body by feeding on plant tissue or sucking on plant juice, playing a toxic role, such as dimethoate.

According to toxicological effects, insecticides can be classified as:

① Neurotoxic agents. It acts on the nervous system of pests, such as DDT, parathion, carbofuran, Pyrethrin, etc.

② Respiratory agents. Inhibit respiratory enzymes of pests, such as cyanuric acid.

③ Physical agents. Mineral oil agents can block the valve of pests, while inert powder can abrade the skin of pests and cause them to die.

④ Specific insecticides. Causing abnormal physiological reactions of pests, such as repellents that keep pests away from crops, attractants that lure pests with sexual or bait, antifeedants that inhibit their taste and no longer feed, leading to starvation and death, sterile agents that act on adult reproductive function to cause infertility of either male or female, and insect growth regulators that affect the growth, metamorphosis, and reproduction of pests.

Development Direction

① Global climate change triggers activities of pests and diseases, which in turn leads to an increase in pesticide use. In agricultural production, the occurrence of pests and diseases is closely related to climate change. If climate conditions are unfavorable for the growth of pests and diseases, the degree of occurrence of pests and diseases will be greatly reduced, thereby reducing the use of pesticides.

② Insecticides still maintain the dominant position in the international pesticide market, with three major types of pesticides, namely insecticides, fungicides, and herbicides, being the main players in the international pesticide market. In 2009, insecticides still accounted for 25% of the global pesticide market, with North America and Western Europe maintaining the largest market share, accounting for approximately 70% of the entire market.

③ As the global pesticide industry continues to develop, it is also facing a series of new requirements, that is, the use of pesticides over the years has caused varying degrees of pollution to the environment and humans and livestock. Therefore, the international community has increasingly high requirements for efficient, low toxicity, low residue, and pollution-free pesticides, especially in the pesticide industry.