Fumigant toxicity and sublethal effects of Teucrium polium essential oil on Aphis fabae scopoli A

Abstract

ObjectiveBlack bean aphid (Aphis fabae) is one of the most important greenhouse and crop pests with a wide range of hosts, which causes damages through feeding on vegetable sap and transmitting viral diseases. Currently, chemical methods are mainly used to control this pest. Considering the adverse effects of pesticides, it is essential to apply less chemical pesticide in pest control programs. The lethal and sublethal effects of the essential oil (EO) of Teucrium polium leaves on one-day-old adults of black bean aphid were investigated under laboratory conditions. MethodThe bioassay was evaluated at the concentrations of 0.88−12 µL/L air, for 24 h after treatment. Reproductive life table parameters of new emerged aphid surveyed at sub-lethal concentrations (LC20 and LC40) of EO and the biological reproductive table was calculated by Jackknife method. ResultsThe mortality rate increased significantly with the increasing of EO concentration. The estimated LC50 value was 4.5 µL/L air. Laboratory exposure to sublethal concentrations of EO caused significant decrease in adult female longevity and fertility of surviving aphids and as a result caused significant reduction in the intrinsic rate of natural increase (rm value). ConclusionThe results of this study revealed that EO of T. polium could be used as a potential control agent for the aphid.