Bioassay of Essential Oils against Mites

For each experiment, alive mites of all motile stages (n = 20) were placed in a plastic Petri dish (3 cm in diameter). In the first experiment, all the pure essential oils included in the present study were successively tested against mites. The following bioassays were conducted using the essential oils that killed all the mites within 1 h of direct contact. The selected essential oils were diluted with paraffin to get concentrations at 10, 5 and even 1% (for the most efficient ones). In each Petri dish, 1 ml of the diluted solution was added in direct contact with the mites. A control Petri dish was inoculated with 1 ml of paraffin oil. The mites were inspected under a stereomicroscope (Nikon©, SMZ645, Lisses, France) 10, 20, 30, 40, 50, 60, 90, 120, 150 and 180 min after inoculation. Mites were considered dead when no movement was seen even after touching it with a needle, and no gut movement was observed over 2 min [12 (link)].