Our previous study shows that Coptotermes formosanus(Blattodea:Rhinotermitidae)preferred to stay on filter paper treated with ethyl 2,4-dioxovalerate,a metabolite in the soil fungus Trichoderma virens.Here,we hypothes...Our previous study shows that Coptotermes formosanus(Blattodea:Rhinotermitidae)preferred to stay on filter paper treated with ethyl 2,4-dioxovalerate,a metabolite in the soil fungus Trichoderma virens.Here,we hypothesized that adding ethyl 2,4-dioxovalerate in sand could trigger aggregation and tunneling preferences of C.formosanus and improve the effectiveness of liquid termiticide.In aggregation-choice tests,significantly more termites were found on/in sand blocks containing ethyl 2,4-dioxovalerate(250µg/g)than untreated blocks throughout the 24-h experiments.In the tunneling-choice tests,termites also excavated significantly more tunnels in the sand treated with ethyl 2,4-dioxovalerate(2.5,25,or 250µg/g)than untreated sand.However,in no-choice tests,ethyl 2,4-dioxovalerate(2.5,25,or 250µg/g)did not significantly affect tunneling activities,termite survival,wood consumption,or activities of detoxification enzymes(peroxidase,superoxide dismutase,and catalase)compared to controls.Interestingly,in aggregation-and tunneling-choice tests,termites preferred to stay and made more tunnels in sand treated with both ethyl 2,4-dioxovalerate(250µg/g)and fipronil(1µg/g)than untreated sand.In addition,in choice tests,sand treated with the combination of ethyl 2,4-dioxovalerate(250µg/g)and fipronil(1µg/g)caused significantly higher termite mortality than the sand treated with only fipronil(1µg/g).Our study showed that ethyl 2,4-dioxovalerate may enhance the effectiveness of fipronil(1µg/g in sand)by triggering aggregation and tunneling preferences of termites,thereby increasing the contact between termites and fipronil.展开更多
文摘Our previous study shows that Coptotermes formosanus(Blattodea:Rhinotermitidae)preferred to stay on filter paper treated with ethyl 2,4-dioxovalerate,a metabolite in the soil fungus Trichoderma virens.Here,we hypothesized that adding ethyl 2,4-dioxovalerate in sand could trigger aggregation and tunneling preferences of C.formosanus and improve the effectiveness of liquid termiticide.In aggregation-choice tests,significantly more termites were found on/in sand blocks containing ethyl 2,4-dioxovalerate(250µg/g)than untreated blocks throughout the 24-h experiments.In the tunneling-choice tests,termites also excavated significantly more tunnels in the sand treated with ethyl 2,4-dioxovalerate(2.5,25,or 250µg/g)than untreated sand.However,in no-choice tests,ethyl 2,4-dioxovalerate(2.5,25,or 250µg/g)did not significantly affect tunneling activities,termite survival,wood consumption,or activities of detoxification enzymes(peroxidase,superoxide dismutase,and catalase)compared to controls.Interestingly,in aggregation-and tunneling-choice tests,termites preferred to stay and made more tunnels in sand treated with both ethyl 2,4-dioxovalerate(250µg/g)and fipronil(1µg/g)than untreated sand.In addition,in choice tests,sand treated with the combination of ethyl 2,4-dioxovalerate(250µg/g)and fipronil(1µg/g)caused significantly higher termite mortality than the sand treated with only fipronil(1µg/g).Our study showed that ethyl 2,4-dioxovalerate may enhance the effectiveness of fipronil(1µg/g in sand)by triggering aggregation and tunneling preferences of termites,thereby increasing the contact between termites and fipronil.
