The application of organic insecticides in the agrotechnical praxis resulted in a great and unexpected progress in the control of insect pests, and was of a great economical value all over the world. The widespread application of these agents, however, is also accompanied by negative effects. The principal drawback of classical insecticides consists in the lack of their specificity, the useful insects being killed together with insect pests. Furthermore, the broad-scale application for many years led to the formation of more resistant insect strains requiring higher and higher doses of...