As early as 3000 years ago, Homer mentioned "sulfur to avoid harm" in Odessa. It can be considered that this is the earliest report on the use of pesticides. In 176 1, copper sulfate is used to control head smut of grain. The earliest foliar fungicide was also sulfur-copper suspension. 1763 French news reports recommend tobacco and lime powder to control aphids. This is the first pesticide reported in the world, and its main effective component is nicotine. Nicotine, the first generation pesticide, is the earliest pesticide used. Second, the development status of pesticides 1. In the early 1940s, phenoxyacetic acid compounds were synthesized and produced, and herbicides were produced, which also marked the beginning of modern chemical weeding technology. 2. In the 1940s, a large number of new varieties with different structural types appeared. Organochlorine pesticides such as DDT, bhc, toxaphene, chlordane, acetaldehyde, heptachlor, organophosphorus pesticides such as chlorpyrifos, parathion (1946) and terbutamol, and fungicides such as sodium, manganese and zineb. DDT is one of the most famous varieties.