Author/Authors :
abdellaoui, khemais sousse university - higher institute of agronomy - department of biological sciences and plants protection, Chott Mariem, TUNISIA , acheuk, fatma university of boumerdes - faculty of sciences - laboratory of valorization and conservation of biological resources”valcore”, department of biology, Boumerdes, ALGERIA , miladi, meriem sousse university - higher institute of agronomy - department of biological sciences and plants protection, Chott Mariem, TUNISIA , boughattas, iteb sousse university - higher institute of agronomy - department of biological sciences and plants protection, Chott Mariem, TUNISIA , omri, ghofrane sousse university - higher institute of agronomy - department of biological sciences and plants protection, Chott Mariem, TUNISIA
Abstract :
The confused flour beetle, Tribolium confusum (Coleoptera: Tenebrionidae) is a common pest insect known for attacking and infesting stored flour and grain. Biodegradable and ecologically natural products such as essential oils are emerging candidates for replacement of usually applied chemical pesticides. The essential oils of Ruta chalepensis flowering aerial parts were investigated for their contact toxicity and physiological aspects on T. confusum. Essential oils were obtained by hydrodistillation and 56 components were identified by GC-MS. Our results clearly indicated that these compounds exhibited toxicity against T. confusum pupae and adults with an LC50 value of 0.08 and 0.055 μL/cm², respectively after 7 days of treatment. In repellency assay, essential oils repelled T. confusum adults significantly even at 0.06 μL/cm² concentration in an area preference test. Result also showed that maximum exposure time resulted in maximum repellency of the pest at all the concentrations. The repellent activity could be related to the abundance of the 2-undecanone (25.94%) in the oils. In other experiments, the essential oils were investigated on the activities of acetylcholinesterase (AChE) and glutathione S-transferases (GSTs). Biochemical analysis demonstrated that the essential oils of R. chalepensis induced GSTs and reduced the activity of AChE. Based on these results, essential oils of R. chalepensis origin could have greater potential in future in stored-product pest management.
Keywords :
Essential oils , phytochemistry , toxicity , Acetylcholinesterase , glutathione S , transferases
