Devonshire_1973_Pest.Sci_4_521

Resum The mechanisms by which insects chemically modify and thereby resist insecticides, and the techniques used to study this metabolism arc described. The enzymes associated with the endoplasmic reticulum of the cell (the microsomal enzymes) play a major and ubiquitous role in this metabolism which can produce molecules either more or less toxic than the insecticide applied. Soluble enzymes in the cytoplasm of the cell also metabolise insecticides, and it is the balance between these types of metabolism and such factors as the rate of penetration of the insecticide and the susceptibility of the target which determines the tolerance of an insect to a particular insecticide. A very small change in one of these factors can cause a large change in the dose of insecticide required to kill an insect.