Electroantennogram Responses of the Tea Slug Moth, Iragoides fasciata to Some Plant Volatiles Associated with Tea, Camellia sinensis

Electroantennogram responses to a wide range of plant volatile compounds that have been identified in tea plants Camellia sinensis L. (Ericales: Theaceae) were recorded from males and females of the tea slug moth, Iragoides fasciata Moore (Lepidoptera: Limacodidae). The responses to 26 compounds, belonging to several chemical classes, and two mixtures were evaluated. The results showed significantly different electroantennogram responses to the different chemicals, as well as significantly different responses according to gender. The green leaf volatile components elicited significantly greater responses in males. In general, the antennae of males were more sensitive, and responded more strongly, to most of the compounds. Responses to sesquiterpenoids were lower in both males and females. Dose-dependent response studies indicated differences in response between genders and concentrations, suggesting the existence of sexual dimorphism. Compounds belonging to the green leaf volatiles class appeared to be important clues in host-plant selection by this oligophagous species.