Prey location by the predatory mites <em>Neoseiulus californicus</em> and <em>Phytoseiulus persimilis</em> (Acari: Phytoseiidae) under exposure to chlorfenapyr and acequinocyl

Abstract

Biological control is widely regarded as a sustainable and eco-friendly approach to pest management. However, the use of acaricides may occasionally be required as a supplementary measure. This study investigated the effect of two acaricides, chlorfenapyr and acequinocyl on the olfactory response of the predatory mites, Neoseiulus californicus (McGregor) and Phytoseiulus persimilis Athias-Henriot (Acari: Phytoseiidae). In olfactory assays, mites were exposed to acaricide-treated or control discs and then introduced into a Y-tube olfactometer to evaluate their response to odor sources (healthy vs. spider mite-infested leaves). G-test was employed for data analysis. The results showed that predatory mites treated with sublethal concentrations of acaricides moved randomly between Y-tube arms, while control mites and those in the acequinocyl field concentration treatment showed a significant preference for the arm containing spider mite odor, indicating that no disruption in odor tracking occurred. With increasing acaricide concentration, the number of mites that hesitated to choose between the two arms of the Y-tube increased. Furthermore, the average time taken for mites to select, and reach the odor source increased in treatments with higher concentrations, indicating that higher pesticide levels impair the mites' ability to detect and respond to prey odors. These findings highlight the disruptive effects of pesticides on predatory mites' olfactory pathways, which could compromise their role in biological control. To preserve their effectiveness, careful selection and use of pesticides are essential. Moreover, incorporating olfactory response studies into pesticide selectivity evaluations can further support integrated pest management programs.

Keywords

• Acaricide
• bioassay
• biological control
• olfactory response
• predatory mite