Fumigant toxicity and sublethal effects of Thymus munbyanus essential oil on biomarkers, reproduction, and locomotion in the Mediterranean flour moth Ephestia kuehniella

This study evaluated the fumigant toxicity of Thymus munbyanus subsp. coloratus essential oil against adult Ephestiakuehniella (Zeller). To determine sublethal effects, we integrated biochemical biomarkers with assessments of reproductiveperformance and locomotor activity. Adults were exposed via fumigation to concentrations between 0.05 and 0.8 ?L/mLof air, with lethal concentrations calculated after 24 h of exposure. The essential oil showed strong fumigant activity, with \mathrm{LC_{25}} and \mathrm{LC_{50}} values of 0.153 and 0.26 ?L/mL of air, respectively. Sublethal exposure at these concentrations was associatedwith changes in biomarker responses in adults, including increased glutathione S-transferase (GST) and catalase (CAT)activities, along with decreased acetylcholinesterase (AChE) activity. In addition, fumigation affected adult reproductiveperformance by reducing oviposition, as reflected by a decrease in the number of eggs laid and hatched. Locomotor activitywas also impaired, with reductions in distance traveled, movement duration, and movement speed. Overall, these findingssuggest that T. munbyanus essential oil has potential as a botanical fumigant against E. kuehniella adults.