The effects of essential oils from eight plant species on two pests of stored product insects

Essential oils obtained from eight different plant species including Origanum acutidens (Hand-Mazz), Satureje hortensis L., Hypericum scabrum L., Thymus vulgaris L., Micromere fruticosa (Bertol.), Salvia limbata C. A. Meyer, S. nemerosa L. and Hyssoppus officinalis L. were tested against Sitophilus granarius adults and Ephestia kuehniella larvae. Essential oils of O. acutidens, S. hortensis and H. scabrum were found to have similar anti-insecticidal effects on both pests, adults of S. granarius and larvae of E. kuehniella, but not on other ones. The results showed that there were significant differences between doses and exposure period of the essential oils tested. Mortality rate in S. granarius adults and E. kuehniella larvae increased with dose of essential oils and their exposure period. The average mortality rates with a dose of 10 mul essential oils of O. acutidens, S. hortensis, H. scabrum, T vulgaris, M fruticulosa, S. limbata, S. nemerosa and H. officinalis were approximately 74 %, 66 %, 73 %, 4 %, 12 %, 7 %, 10 %, and 14 % for S. granaries, and 79 %, 62 %, 72 %, 24 %, 24 %, 6 %, 0 %, and 14 % for E. kuehniella, respectively. No mortality was observed in the control group of each species.