تاثیر کنه‌کش‌های کلرفناپیر و آسکینوسیل بر کشندگی، رفتار دفع کنندگی و پاسخ بویایی کنه شکارگر Phytoseiulus persimilis (Acari: Phytoseiidae)

The two-spotted spider mite (Tetranychus urticae Koch) is a major global pest of plants. Excessive use of chemical pesticides has led to its resistance to these chemicals. Therefore, biological control using predatory mites such as Phytoseiulus persimilis Athias-Henriot is an alternative approach for managing this pest. This study evaluated the toxicity of chlorfenapyr and acequinocyl acaricides on this predatory mite. The walking behavior and olfactory response of this mite after exposure to residues of these acaricides were then investigated using a video tracking system and a Y-shaped olfactometer. To assess the repellency and attractancy of the acaricides, PVC discs were divided into two hemispheres, and each hemisphere was separately immersed in distilled water or acaricide solution. The repellency or irritability of the acaricides was then evaluated based on the time spent by the mites on each hemisphere. According to the results, the LC50 values of both acaricides were estimated to be higher than the field concentration, and chlorfenapyr was five times more toxic than acequinocyl. In the behavioral assay, both compounds significantly affected the distance and speed of movement, rest time, and frequency of stops. Both compounds also had irritable properties for this mite, as the mites avoided areas contaminated with pesticide residues and spent significantly more time in the uncontaminated area than in the contaminated area (P < 0.05). Additionally, exposure to sublethal concentrations impaired the ability of this mite to track odor sources in the Y-shaped tube (comprising spider mite-infested bean leaf and healthy bean leaf). The treated mites moved randomly between the two arms of the tube and their choice time increased, while the control mites showed a significant preference for the arm containing the spider mite odor. Only the lowest concentration treatment of acequinocyl (recommended dose) did not have a negative effect on the mite's olfactory response, suggesting that this acaricide is less risky for this mite. According to the results of this study, P. persimilis mites have the ability to detect pesticide residues in their environment and try to avoid them. Pesticides can also reduce the ability of predatory mites to detect and track prey odors. This disruption can potentially jeopardize the effectiveness of biological control, so careful selection and use of pesticides are essential to maintain the efficacy of biological control. In this study, both acaricides pose low risk to this predatory mite, but acequinocyl is much safer and is a suitable option for use in integrated pest management (IPM).