Acaricidal effect of two plant essential oils Pimpinella anisum and Satureja bachtiarica on two-spotted spider mite Tetranychus urticae (Acari: Tetranychidae)

The two-spotted spider mite, Tetranychus urticae is an important pest because of the word wide distribution, extensive host range, severe damage, great rate of population growth and ability in creating resistance against pesticides. In the present study, the acaricidal effect of the essential oils of two plant species, Pimpinella anisum L.and Satureja bachtiarica Bungewere tested against the adults of Tetranychus urticae. Air-dried plant materials including seeds of P.anisum and herbage of S.bachtiarica, were distilled using a circulatory Clevenger-type apparatus. The essential oil was dried over anhydrous sodium sulphate and stored at ºC until tested. The amounts of the essential oils for P.anisum applied were 3.33, 6.66, 13.33, 26.66 and 53.33 μl/L air and for S.bachtiarica were 0.166, 0.33, 0.66, 1.33 and 2.66 μl/L. The vapours of these two plant species were toxic to adults of T. urticae. The value of LC50 on adults were 10.63 μl/L air for P.anisum and 0.33 μl/L air for S.bachtiarica. Also with increasing oil concentration, mortality rate of adults increased. According to results the P.anisum and S.bachtiarica essentials oil are appropriate in integrated pest management of two-spotted spider mite and can be considered as bio-pesticide.