Physiological and Ecological Selectivity of Pesticides for Natural Enemies of Insects

Insecticides used in integrated pest management (IPM) can be also detrimental to natural enemies that are naturally present or released in the agroecosystems. Besides the mortality caused by pesticides, sublethal effects (such as reduction in fecundity, fertility, predation/parasitism rates, among others) can be observed on predators and parasitoids. Therefore, assessing the noxiousness of these chemical compounds to beneficial organisms, aiming at the integration of chemical and biological methods in pest control, is important to form the grounds for the development of more efficient, rational, and sustainable IPM programs. This chapter focuses on concepts related to the selectivity of pesticides to beneficial arthropods in pest control. After an introduction covering some aspects regarding pest management and concepts related to selectivity of pesticides, we present results of studies on the effects of pesticides on natural enemies in Neotropical countries. Many of these studies were performed according the methodologies proposed by the International Organization for Biological and Integrated Control of Noxious Plants and Animals (IOBC), including fitting the compounds into toxicity and persistence classes. The research focuses on lethal and sublethal effects of phytosanitary products on natural enemies, in different exposition routes (topical application, residual contact, feeding on treated material, etc.) and life stages of the predators and parasitoids. Sublethal effects included alterations on behavior and biological parameters (i.e., reproduction and development). With this information, it is possible to decide whether an insecticide and a natural enemy can be used together in IPM programs, enhancing pest control. This research field should be stimulated to incorporate new strategies to pest management in Latin America.