Chemical Composition and Insecticidal Activity of Myrtle (Myrtus communis L.) Essential Oil against Two Stored-Product Pests

Essential oil extracted from the leaves of Myrtle, Myrtus communis L. (Myrtaceae)was tested in vitro for volatile toxicity against two stored-product insects (Tribolium confusum and Callosobruchus maculatus). The chemical composition of the plant oil was examined by gas chromatography-mass spectrometry (GC-MS). The major oil components were α-pinene (۱۰.۴%), α- Terpineol (۱۰.۱%), linalool (۹.۰%), ۱, ۸-cineole (۷.۶%), Geranyl butyrate (۶.۳%), Geraniol (۶.۲%), Caryophyllene oxide (۵.۳%) and Neryl acetate (۵.۰%). In the fumigant toxicity test, significant differences in mortality of insects to essential oil vapor were observed in different concentrations after an exposure time of ۲۴ hours. C. maculatus (LC۵۰=۹.۵ µl/l air) was more susceptible to the plant oil than T. confusum (LC۵۰=۲۶۰.۷ µl/l air). The results suggested that essential oil of M. communis L. could be used as a potential biocontrol agent for stored-product insects.

Keywords:

fumigant toxicity , GC-MS , Myrtus communis L , Stored-products , essential oil