Repellent activity and persistence of essential oil from Eucalyptus salmonophloia F. Muell and Eucalyptus kingsmillii (Mauden) Maiden & Blakely on two spotted spider mite, Tetranychus urticae Koch

Two-spotted spider mite Tetranychus urticae Koch is one of the most well known polyphagous pests of crops in the world. Due to undesirable effects of synthetic pesticides such as expression of resistance in mites, this research was conducted to achieve alternative safe compounds to environment. Therefore, in this Research, repellent activity and persistence of two plant essential oils, including of Eucalyptus salmonophloia F. Muell and Eucalyptus kingsmillii (Mauden) Maiden & blakely, were studied on T. urticae, at 27 ± 0.5 °C, 50 ± 0.5% RH and photoperiod of 16:8 h (L:D). The essential oils were extracted using Clevenger-type apparatus. According to the repellency index formula, it was found that both essential oils of E. salmonophloia and E. kingsmillii from 4 applied concentrations were only repellent in two concentrations. Generally, no significant differences of repellency were found between two plant essential oils of E. salmonophloia and E. kingsmillii at different concentrations. In repellency experiment for essential oils, it was found that no significant differences were observed between essential oils of E. salmonophloia and E. kingsmillii. Our findings indicated that Eucalyptus species had reliable repellent activity and persistence on T. urticae. However, more research is necessary to make these compounds applicable.