Progress in research on the relative fitness of insecticide-resistant insects

Author of the article:WANG Zheng-Yan WANG Wen-Fang MIAO Shi-Yuan LU Yu-Jie

Author's Workplace：School of Food Science and Technology, Henan University of Technology, Zhengzhou 450001, China

Key Words：insecticide resistance; fitness; deleterious effects; allelic replacement; modifier genes; resistance management

Abstract：Fitness changes associated with insecticide resistance are a consequence of biochemical and physiological changes associated with resistant genotypes. Relative fitness of insecticide resistant insects can be defined either as selection pressure acting against the mutations conferring resistance in natural populations, or as resistance-associated change in physiology and/or in life history traits. Changes in target receptors or metabolic enzymes can disrupt normal molecular process, and over-expression of an enzyme or receptor might divert energy from fitness-enhancing functions. Both kinds of change lead to a tradeoff between resistance and other fitness-related traits. Nevertheless, allelic replacement and modifier genes can be selected to ameliorate the cost of resistance. Phenotypes of relative fitness are dependent on a population’s genetic background during the evolution of resistance and resistance levels and are also influenced by ecological factors. Knowledge of the relative fitness of resistant insects improves understanding of the evolutionary processes of insecticide resistance and resistance management.