Olfactory Identifying Mechanisms Of Adelphocoris Suturalis, Adelphocoris Lineolatus And Adelphocoris Fasciaticollis (Hemiptera:Miridae) To Host Plant Volatiles

Mirid bug (Hemiptera:Miridae), a group of key insect pests, has abundant species and wide distribution. The genus Adelphocoris has caused serious damage to cotton and other cultivated plants, mainly including Adelphocoris suturalis (Jakovlev), Adelphocoris li0neolatus (Goeze) and Adelphocoris fasciaticollis (Reuter) in China. In this work, we studied the chemical communication mechanisms between these three Adelphocoris spp. and their host plants. The main results were summarized as follows:The results of Coupled gas chromatography-electroantennography (GC-EAD) and gas chromatography-mass spectrometer (GC-MS) analysis revealed the presence of totally seven electrophysiologically active volatile compounds (m-xylene, p-xylene, n-butyl ether, butyl acrylate, butyl propionate, butyl butyrate and 1,8-cineole) from A. suturalis’s host plants, including Gossypium hirsutum L., Achyranthes bidentata Blume, Artemisia argyi Levl. et Vant, Artemisia lavandulaefolia DC, Astragalus complanatus Bunge, Melilotus suaveolens Ledeb. and Mentha haplocalyx Briq. EAG dose-dependent responses revealed that EAG amplitude of A. suturalis increased as the concentration increased. Butyl acrylate, Butyl propionate and Butyl butyrate elicited higher response than other active volatile compounds. In Y-tube olfactometer bioassays, male and female A. suturalis adults both obviously responded to n-butyl ether, butyl acrylate, butyl propionate and butyl butyrate, whereas they showed no response to m-xylene, p-xylene or 1,8-cineole.Six electrophysiologically active volatiles were identified from five host plants (A. argyi, A. lavandulaefolia, G hirsutum, Medicago sativa and M. suaveolens.) for A. lineolatus, including p-xylene, n-butyl ether, butyl acrylate, butyl propionate, butyl butyrate and 1,8-cineole. EAG amplitude increased as the concentration increased, except the EAG response to p-xylene for both sexes and to butyl acrylate for females. Female and male A. lineolatus showed relatively higher EAG response to butyl acrylate, butyl propionate and butyl butyrate. In Y-tube olfactometer bioassays, male and female A. lineolatus adults exhibited a significantly behavioral response to p-xylene, n-butyl ether, butyl acrylate, butyl propionate and butyl butyrate, while there are no difference in behavioral selection between control and 1,8-cineole.Seven active volatile compounds (p-xylene, n-butyl ether, butyl acrylate, butyl propionate, butyl butyrate, β-pinene and 1,8-cineole) were identified from the main host plants of A. fasciaticollis, including A. lavandulaefolia, A. scoparia Waldst. et Kit., Cannabis sativa L., G. and M. sativa. EAG analysis indicated that antennal response of A. fasciaticollis adults increased as the concentration increased (except female to β-pinene), and A. fasciaticollis males were more often responsive to active volatiles than females. Additionally, EAG responses of A. fasciaticollis adults to butyl acrylate, butyl propionate and butyl butyrate were among the strongest. Male and female A. fasciaticollis were attracted to butyl acrylate, butyl propionate and butyl butyrate, whereas there are no difference between control and other four active compounds.In this study, we explored chemical communication mechanisms between A. suturalis, A. lineolatus, A. fasciaticollis and their main host plants, by using electrophysiological and behavioral bioassays. Our results provide groundwork for further understanding the interaction between Adelphocoris spp. and their host plants, and the development of environmentally sound and sustainable management schemes of these pestiferious mirid bugs.