title: Analytical methods for detecting pesticide switches with evolution of pesticide resistance.
abstract: After a pest develops resistance to a pesticide, switching between different unrelated pesticides is a common management option, but this raises the following questions: (1) What is the optimal frequency of pesticide use? (2) How do the frequencies of pesticide applications affect the evolution of pesticide resistance? (3) How can the time when the pest population reaches the economic injury level (EIL) be estimated and (4) how can the most efficient frequency of pesticide applications be determined? To address these questions, we have developed a novel pest population growth model incorporating the evolution of pesticide resistance and pulse spraying of pesticides. Moreover, three pesticide switching methods, threshold condition-guided, density-guided and EIL-guided, are modelled, to determine the best choice under different conditions with the overall aim of eradicating the pest or maintaining its population density below the EIL. Furthermore, the pest control outcomes based on those three pesticide switching methods are discussed. Our results suggest that either the density-guided or EIL-guided method is the optimal pesticide switching strategy, depending on the frequency (or period) of pesticide applications.
authors.affiliation: College of Mathematics and Information Science, Shaanxi Normal University, Xi'an 710062, People's Republic of China.
authors.forename: Juhua
authors.initials: J
authors.lastname: Liang
authors.forename: Sanyi
authors.initials: S
authors.lastname: Tang
authors.forename: Juan J
authors.initials: JJ
authors.lastname: Nieto
authors.forename: Robert A
authors.initials: RA
authors.lastname: Cheke
mesh_terms: D000818:Animals; D019295:Computational Biology; D004351:Drug Resistance / Q000235:genetics; D019143:Evolution, Molecular; D006801:Humans; D055641:Mathematical Concepts; D008954:Models, Biological; D010571:Pest Control / Q000379:methods* / Q000706:statistics & numerical data; D010575:Pesticides / Q000494:pharmacology*; D011158:Population Growth; D013997:Time Factors
chemical_list: D010575:Pesticides
keywords: Dynamic threshold; Evolution; Pesticide application frequency; Pesticide switches; Pulse spraying