Comparative Toxicity of Selected Acaricides and Essential Oils to Tetranychus Urticae Koch and its Predatory Mite Phytoseiulus persimilis Athias-Henriot Under Controlled Laboratory Conditions

Anter, M. A .; Mokhtar, Aida H. M.; Ibrahim, Noha A.; Abdel–Kader, S. A.

doi:10.21608/jppp.2025.396516.1352

Comparative Toxicity of Selected Acaricides and Essential Oils to Tetranychus Urticae Koch and its Predatory Mite Phytoseiulus persimilis Athias-Henriot Under Controlled Laboratory Conditions

Document Type : Original Article

Authors

¹ Department of Plant Protection, Faculty of Agriculture, Al-Azhar University, Cairo

² Scale and Mealy bug Research Department Plant Protection Research Institute, Agricultural Research Center, 12619,Giza, Egypt

³ Cotton and Crop Mites Research Department, Plant Protection Research Institute, Agricultural Research Center 12619 Dokki, Giza, Egypt.

10.21608/jppp.2025.396516.1352

Abstract

A laboratory study was performed to assess the acute toxicity of four synthetic acaricides (emamectin benzoate, chlorfenapyr, hexythiazox, and acequinocyl) and four essential oils: eucalyptus oil (Eucalyptus globulus), thyme oil (Thymus vulgaris), garlic oil (Allium sativum), and cinnamon oil (Cinnamomum zeylanicum) against the two-spotted spider mite (Tetranychus urticae) and its natural predator Phytoseiulus persimilis after 24 and 48 hours of exposure. Among all tested compounds, emamectin benzoate showed the highest toxicity across both time points, with the lowest LC50 values (2.86 and 2.42 mg/L, respectively). Chlorfenapyr followed with moderate toxicity and delayed lethal effects. Hexythiazox and acequinocyl demonstrated low toxicity after 24 hours but slightly improved efficacy by 48 hours, reflecting their mode of action and slow adulticidal effects. Among essential oils, eucalyptus oil showed the highest toxicity followed by thyme oil although both required much higher concentrations than synthetic acaricides. Garlic oil and cinnamon oil exhibited weak acaricidal activity. Comparative toxicity on the predatory mite P. persimilis indicated that both emamectin benzoate and chlorfenapyr had low selectivity as they caused high mortality and had low LC50 values on the predator. In contrast, hexythiazox and acequinocyl were more selective and safer to the predatory mite. These results highlight the potential of integrating selective acaricides and essential oils within Integrated Pest Management (IPM) programs, emphasizing the need to balance efficacy against T. urticae with safety to natural enemies.

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