Behavioral and physiological responses of Drosophila melanogaster and D. suzukii to volatiles from plant essential oils

Abstract

BACKGROUND Insects rely on their sense of smell to locate food and hosts, find mates and select sites for laying eggs. Use of volatile compounds, such as essential oils (EOs), to repel insect pests and disrupt their olfaction‐driven behaviors has great practical significance in integrated pest management. However, our knowledge on the olfaction‐based mechanisms of EO repellency is quite limited. RESULTS We evaluated the repellency of peppermint oil and nine plant EO components in Drosophila melanogaster, a model insect for olfaction study, and D. suzukii, a major fruit crop pest. All nine volatiles, menthone, (−)‐menthol, menthyl acetate, (R)‐(+)‐limonene, nerol, (+)‐fenchone, (−)‐α‐thujone, camphor, norcamphor and peppermint oil, elicited repellency in D. melanogaster in a dose‐dependent manner. Most of the compounds, except camphor, also elicited repellency in D. suzukii. Menthone, (R)‐(+)‐limonene and (+)‐fenchone were the most potent repellents against D. suzukii. Repellency was reduced or abolished in two D. melanogaster mutants of the odorant receptor co‐receptor (Orco), indicating that the observed repellency is odorant receptor (Or)‐mediated. Repellency by peppermint oil, menthone, (R)‐(+)‐limonene, (−)‐α‐thujone and norcamphor also involves Or‐independent mechanism(s). Single sensillum recording from both species revealed that common and distinct Ors and olfactory receptor neurons were activated by these compounds. CONCLUSIONS The tested plant EO components evoke repellency by activating multiple Ors in both Drosophila species. Our study provides a foundation for further elucidation of the mechanism of EOs repellency and species‐specific olfactory adaptations. © 2021 Society of Chemical Industry

Encapsulation of Basil Essential Oil by Paste Method and Combined Application with Mechanical Trap for Oriental Fruit Fly Control

“…Gomez-Diaz, Martin, Garcia-Fernandez, and Alcorta [ 58 ], Leal [ 60 ] described that the insect sensilla comprises pores in the cuticle that allow odorants to diffuse into the nerve system. The located ORs are also described as odour-specific, especially natural products such as essential oils [ 61 , 62 ]. In the ORF, in particular, its ORs are able to bind structurally with all portions of methyl eugenol molecule and respond to ortho-substituted benzenes with adjacent oxygen atoms or isoelectronic equivalents [ 63 ].…”

Electrophysiological and Behavioral Responses of Holotrichia parallela to Volatiles from Peanut

“…Plant volatiles can act as important chemical signals that form communication links between insect herbivores and their host plants and function as either attractants or repellents [15,16]. In this study, we investigated which peanut volatile components play a role in host plant selection in H. parallela.…”

Identification of multiple odorant receptors essential for pyrethrum repellency in Drosophila melanogaster

“…Pyrethrum also repelled D. suzukii in these assays (S1 Fig). Furthermore, we performed the two-choice assay in the presence of an attractant, apple cider vinegar (ACV), i.e., a two-choice attraction assay [24] (S1 Fig) and found that both D. melanogaster and D. suzukii were repelled by pyrethrum in this assay as well (S1 Fig).…”

“…Single sensillum recording was conducted with electrolytically sharpened tungsten microelectrodes as previously described [13,24,31]. A 0.1 mm diameter tungsten wire was sharpened by repeatedly dipping its tip in a 10% KNO 2 solution electrified at 5-10 mV.…”