Modeling resistance to juvenile hormone analogs: Linking evolution, ecology, and management

Juvenile hormone analogs (JHAs) are insecticides that mimic insect juvenile hormone and interfere with normal insect development. JHAs disrupt a hormonal system that is specific to insects and thus kill some target pests while causing less harm to nontarget organisms than broad-spectrum insecticides. JHAs have become increasingly important in agriculture worldwide, where their specificity and efficacy has been used selectively to reduce target pest populations while conserving key natural enemies. Evolution of resistance by target pests, however, can reduce the effectiveness of JHAs. This chapter reviews how models have been used to analyze the evolution of pest resistance to JHAs and to develop strategies to delay pest resistance. We describe results of general mathematical models and a case study showing how simulation, conceptual, and spatially explicit statistical models have been applied to better understand and manage evolution of resistance to the JHA pyriproxyfen by the whitefly, Bemisia tabaci. Our results show how genetic, ecological, and human factors affect evolution of pest resistance to JHAs. Integrating knowledge of these factors into models can help to produce useful predictions about pest resistance to JHAs and to improve management strategies for preserving the effectiveness of this important functional class of insecticides.