Evaluating the repellent effects of major essential oil components (Lamiaceae) on brown dog tick Rhipicephalus sanguineus sensu lato) using the larval repellent activity test

Abstract

This research aims to investigate the repellent effects of five major components of plant essential oils (carvacrol, geraniol, cineole, α-pinene, and γ-terpinene) on the brown dog tick, Rhipicephalus sanguineus sensu lato (Acari: Ixodidae), using the newly developed Larval Repellent Activity Test (LRAT). The components were tested at concentrations of 0.1 %, 0.5 %, 1 %, 2.5 %, and 5 %, with DEET as a positive control. Carvacrol and geraniol exhibited strong repellent effects, with carvacrol showing efficacy comparable to DEET (15 %) at certain concentrations and time points. In contrast, cineole, γ-terpinene, and α-pinene demonstrated moderate to low repellency. The results highlight the potential of using plant-derived components as safer alternatives to synthetic repellents, suggesting that these natural compounds could be developed into effective biocidal products for tick control.

Keywords: Carvacrol; Cineole; DEET; Geraniol; Larval Repellent Activity Test; α-Pinene; γ-Terpinene.