Chemical Composition of Ruta chalepensis Essential Oils and their Insecticidal Activity against Tribolium castaneum

Abstract

Essential oils are secondary plant metabolites well known for their defensive role in plants. Many essential oils were described as having potent insecticidal activity. In the present work, the chemical composition and the insecticidal activity of Ruta chalepensis essential oils against stored product pest Tribolium castaneum (adults and larvae) were investigated. The determination of their chemical composition was carried out by using GC-MS technique. Twenty compounds were identified and results showed that essential oil of R. chalepensis are rich on 2-undecanon (48.28%) and 2-nonanon (27%). The insecticidal activity of the indicated volatile fractions was screened against adults and larvae of T. castaneum. R. chalepensis essential oil was found to be more active against adults (LC50 = 176.075 µl/l air and LC90 = 291.9 µl/l air) than larvae (LC50= 415.348 µl/l air and LC90=685.907 µl/l air). After 24 h of exposure at the dose of 200 µl/l air, 14% and 60% of mortality were recorded for larvae and adults, respectively. These preliminary findings may be useful for further studies of R. chalepensis essential oil use against other food storage pests and for deeper investigations on their mode of action.

Keywords

• Chemical composition
• essential oils
• insecticidal activity
• LC50
• LC90
• Ruta chalepensis
• Tribolium castaneum