Evaluation of Toxicity of Origanum Vulgare, <i>Salvia rosmarinus</i> and <i>Salvia officinalis </i>Essential Oils on <i>Aculops lycopersici</i> in Laboratory Tests

The tomato russet mite (TRM) Aculops lycopersici, a destructive pest of tomato crops worldwide, is a significant challenge to growers, both in greenhouse and open-field conditions. Traditional chemical control methods are often ineffective and set up resistance and adverse environmental impact. This has prompted the exploration of alternative control methods, such as biological control and eco-friendly botanical pesticides. In this study, the acaricidal effects of essential oils (EOs) extracted by three officinal plants, Origanum vulgare L., Salvia rosmarinus Spenn., and Salvia officinalis L., cultivated using precision aromatic crop (PAC) techniques was evaluated against A. lycopersici under laboratory conditions. The chemical composition of EOs was ascertained by a solid-phase microextraction (SPME) coupled with mass spectrometry (GC-MS) analyses. Carvacrol (83.42%), ρ-Cymene (3.06%) and γ-Terpinene (2.93%) were the major components of O. vulgare, while α-Pinene (28.0%), 1,8-Cineole (11.00%) and Borneol (7.72%) were present in S. rosmarinus. 1,8-Cineole (27.67%) was the major constituent of S. officinalis EO, followed by Camphor (21.91%) and Crisantenone (12.87%). Multiple concentrations (320–5000 μL L⁻¹) and exposure times (1 to 4 days) were tested to assess mortality rates. Results showed both dose and time-dependent toxic activity with significant differences among EOs. Oregano EO was found to be the most toxic of the EOs (90% of mortality at 0.5% w/v concentration after 4 days), while rosemary and sage EOs showed limited effects (46% and 42% for the latter EOs respectively). The lethal concentration (LC50) values were 2,228 μL L⁻¹ for oregano, 5,835 μL L⁻¹ for rosemary, and 6,013 μL L⁻¹ for sage, demonstrating ef-ficacy similar to commercially available botanical pesticides. These findings support the potential of O. vulgare EO as a viable alternative for controlling A. lycopersici, contributing to integrated pest management (IPM) strategies, and highlight the need for further re-search for discovering botanical agents for an eco-friendly pest control.