| Fumigant toxicity of Artemisia sieberi, Eucalyptus camaldulensis and Thymus kotschynus essential oils against Blattella germanica (Blattodea: Blattellidae) |
| Paper ID : 1270-3IICE (R1) |
| Authors: |
|
Mehran Rezaei *1, Ramin Khaghani2, Saeid Moharramipour3 1Department of Entomology, Faculty of Agriculture, Tarbiat Modares University, Tehran, Iran, 2Departement of Medical Parasitology, Faculty of Medicine, AJA University of Medical Sciences, Tehran, Iran 3Department of entomology, faculty of agriculture, University tarbiat modares, Tehran.Iran |
| Abstract: |
| The intense application of chemical insecticides has led to the development of insecticide resistance in population of Blattella germanica L. (Blattodea: Blattellidae), a cosmopolitan indoor pest. Therefore, it is important to search for new active compounds as alternative to conventional insecticides. The objective of the current study was to determine the fumigant toxicity of Artemisia sieberi Besser, Eucalyptus camaldulensis Dehn. and Thymus kotschynus Boiss. & Hohen essential oils against first instar nymph and adult stage of B. germanica. Dry ground leaves of plants were subjected to hydrodistillation using a modified Clevenger-type system. To assess 50% (LC50) lethal doses, logarithmic series of dilutions were offered to identify the effective range for 20–80% mortality. The essential oils were applied as pure (1.66 to 66.67 µL/L air) by using a piece of filter paper (2cm diameter) attached to the inner surface of the glass bottle lid (2.5cm diameter). The experiment was conducted at 27 ± 1ºC, 70 ± 5% RH and photoperiod of 16:8 h L:D. Control treatment was considered without the essential oils. Each essential oil concentration was replicated three times for each stage (first instar nymph and adult) and each replication consisted of 10 individuals. The mortality was recorded 24 h after treatment. Data probit analysis demonstrated that the lethal concentration to cause 50% mortality (LC50) and their 95% confidence limits of A. sieberi, E. camaldulensis and T. kotschyanus for the first instar nymph were 15.01 (11.57-18.83), 19.36 (15.56-23.70) and 26.01 (20.89-31.30) µL/L air. Similarly they were 17.30 (12.73-21.80), 21.82 (17.44-26.53) and 28.80 (22.82-34.46) µL/L air for the adult stage, respectively. According to the results, no significant differences were found between the LC50 values of first instar nymph and adult stages among essential oils. However, the LC50 value were significantly higher in A. sieberi and E. camaldulensis compared with those of T. kotschynus. The findings indicate the potential role of the essential oils, in particular A. sieberi and E. camaldulensis as fumigant insecticides against B. germanica in the laboratory conditions. However, further studies are necessary to develop formulations to improve their efficacy and stability and to reduce their costs. |
| Keywords: |
| Mortality, Botanical pesticide, LC50, German cockroach, Fumigation |
| Status : Paper Accepted (Poster Presentation) |
