Bioactivity and chemical composition of forty plant essential oils against the pea aphid Acyrthosiphon pisum revealed peppermint oil as a promising biorepellent

The pea aphid Acyrthosiphon pisum Harris is a major insect pest of Fabaceae crops causing significant damage and economic losses. Its management is a real challenge and the use of plant essential oils (EOs) as biorepellents is a serious alternative to chemical pesticides. Here, we conducted for the first time an in-depth study on the effects of forty plant EOs and their chemical compounds on A. pisum. Using choice bioassays, we reveal the strong repellency of Chinese cinnamon, peppermint, anise, basil, spearmint, and dill oils. Analysis of their chemical composition shows that their respective high contents of trans-cinnamaldehyde, trans-anethole, menthol + menthone, estragole and carvone could be responsible for their high repellency. An additional economic analysis underlines that peppermint EO is the most available and the cheapest. Our data show that peppermint EO with menthol and menthone as major compounds seems to be the most promising EO as biorepellent against the pea aphid. Overall, the repellent activity of peppermint EO may provide a new way to control A. pisum in the future, which may lead to effective strategies for controlling these sucking pests