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AbstractThe two-spotted spider mite, Tetranychus urticaeKoch, one of the major pests of various agricultural plants, causes many problems with agricultural, horticultural and ornamental plants. In recent years, using plant-derived compounds such as essential oils and extracts were attended to their insecticidal and acaricidal properties. The galbanum, Ferula gummosais a native plant of central Asia, was identified as an acaricide plant for the first time of this study. The composition of the essential oil was analyzed by GC-MS. The major components in the oil were β-pinene (50.1%), α- pinene (14.9%) and δ-3-Carene (6.7%). The impact on essential oil of this plant on fumigant toxicity, LT50, oviposition deterrent activity and repellency against T. urticaewas studied at different concentrations. The results stated that F. gummosaoil had high toxicity on eggs and adults of two-spotted spider mite (LC50was 6.98 and 6.52 μL L-1for eggs and adults, respectively). In addition, all tested concentrations had oviposition deterrent activity and repellency on adults of this mite.

AbstractThe cabbage aphid, Brevicoryne brassicaeL. is one of the most important pests of Brassicaceae family. Plant essential oils contain compounds that showed ovicidial, repellency (anti-feeding), unproductive and toxic effects on insects. In this research, insecticial activity and nymph production deterrent of five essential oils was studied on the cabbage aphid in the laboratory conditions under 25 ± 2°C, 65 ± 5% RH and 16L:8D photoperiods. Mortality was evaluated at six different concentrations that ranging from 0.71 to 226.67 μL/L air, and with 6 replications at the interim of 24 hours. The results showed that by increasing dose and time, mortality rate was also increased. The highest and the lowest mortality rate were recorded for Elettaria cardamomumand Citrus sinensis,respectively. Also the highest deterrence percentage is related to LC10for E. cardamomumand the lowest belonged to LC10for C. sinensisand Cinnamomum zeylanicum. It can be concluded that essential oil of E. cardamomumis an appropriate mix and can be used for control of the cabbage aphid in integrated pest management methods.

AbstractToday, to control of stored-product pests the gaseous chemical compound is usually used. These compounds do not have deleterious effects on non target organisms, environment pollutions, insect's resistance, toxicity to humans and other mammals. In recent years, plants essential oils have received much attention because of their insecticidal, oviposition deterency, repellent effects and antifeedant properties. This study was carried out to evaluate the repellent effects of essential oils from Laurus nobilisand Myrtus commonisagainst adults of Ephestia kuehniellaZeller (Lep: Pyralidae). Each essential oil consists of five concentrations and each concentration was repeated five times. Bioassays experiments were performed in 25°C, 65 ± 5 RH and in the dark period at the laboratory condition. The result showed that, repellency rate of this pest was significantly increased by essential oils. Repellency power of both essential oils was increased with increase of oil concentrations. Around 20.4 and 10.6 % repellency rates was observed at the lowest concentration (0.50 µl.L-1air) of L. nobilisand M. commonis, respectively. Also at the highest concentration (2.00 µl.L-1air) repellency rates were reached to 84.2 % by L. nobilisand 61.3 % related to M. commonis. As a result, it could be concluded that essential oils from L. nobilisand M. commonishave considerable repellent effects on E. kuehniellaeven at low concentrations.

AbstractTetranychus urticaeKoch is the major pest of various plants worldwide. Plant compounds are known as biopesticides recently. Essential oil of the oriental arbor-vitae, Thuja orientaliswas researched on repellent and oviposition inhibition of T. urticae. The LC50values of fumigant toxicity of this oil on adults and eggs of the twospotted spider mite were 100.01 and 8.05 μl L-1air, respectively. Also LT50value of essential oil at 100 μl L-1air was 2.06 h. On the other hand, all mites were killed after treatment with 1000 μl L-1concentration. In addition, different concentrations of the essential oil of T. orientalissignificantly affected oviposition deterrence and repellency of adults. The results of this study indicated that essential oil of T. orientalismay be considered as an biopesticide to control spider mites.