Evaluation of the acaricide activity of extracts from eight species of medicinal plants on larvae of Hyalomma anatolicum (Acari: Ixodidae) ticks

The tick Hyalomma anatolicum is the principal species of hard tick that impairs ruminants' productivity in Iran. The purpose of this study is to evaluate the acaricide activity of eight products of plant origin. The ethanolic extract of Achillea millefolium, Ailanthus altissima, Rosmarinus officinalis, Eucalyptus camaldulensis, Lavandula angustifolia, Mentha piperita, Nicotiana tobacum leaves, and Allium sativum cloves were investigated at four concentrations (25, 50, 100, and 200 mg/ml) against H. anatolicum larvae. The modified "larval packet test" was performed on approximately 100 larvae of H. anatolicum at 14–21 days of age. At the highest concentration (200 mg/ml), the larval mortality was 100, 65.00, 46.66, and 43.33 % for N. tobacum, A. sativum, Ac. millefolium, and L. angustifolia extracts, respectively, showing higher mortality than at the lowest concentration. Ai. altissima and R. officinalis extracts had no considerable effect on the mortality percentages of larvae (21.33 %) at the highest concentration. The results show that the extracts of N. tobacum leaves and A. sativum cloves have good acaricidal properties and merit further investigation as alternative approaches to control the H. anatolicum tick.