Lethal and sublethal effects of fluralaner on the citrus red mite, Panonychus citri (McGregor)

Abstract

BACKGROUNDThe citrus red mite, Panonychus citri (McGregor) is a globally distributed agricultural pest. Of late, resistance to common acaricides has raised concerns that chemical control of P. citri is an inefficient means of control. Fluralaner, a highly toxic isoxazoline insecticide used to treat various ectoparasites, presents one potential alternative. However, little information has been reported about the effect of fluralaner on the citrus red mite. This study aims to evaluate the toxicity, sublethal and transgenerational effects of fluralaner on P. citri.RESULTSIn both lab and field populations of P. citri¸ we found fluralaner to be more toxic than conventional alternatives, including fenpropathrin, bifenazate, azocyclotin, and chlorpyrifos. Interestingly, fluralaner proved more toxic to female adults than to the eggs of P. citri, with LC50 of 2.446 and 122.7 mg/L, respectively. Exposure to concentrations of fluralaner (LC10, LC20, and LC30) significantly reduced the fecundity and longevity of female adults P. citri individuals. Although concentrations of fluralaner applied to the parental female adults (F0) led to some changes in the developmental parameters, there were no significant changes in most of life table parameters or population growth of the F1 generation.CONCLUSIONOur results indicate that fluralaner is highly toxic to P. citri, and significant sublethal effect on F0 could suppress the population growth of P. citri, but not for F1. Fluralaner may be considered as a pesticide for the future management of the citrus red mite.