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 (10.4%), α- terpineol (10.1%), linalool (9.0%), 1, 8-cineole (7.6%), geranyl butyrate (6.3%), geraniol (6.2%), caryophyllene oxide (5.3%) and neryl acetate (5.0%). 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 24 hours. c. maculatus (lc50=9.5 µl/l air) was more susceptible to the plant oil than t. confusum (lc50=260.7 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.