Induction of defensive response against herbivores and accumulation of a putative glycoside compound in intact tomato plants in response to volatiles from conspecific plants infested by common cutworm

Herbivore-infested plants are known to emit a specific blend of volatiles. Such a blend is specific in plant and herbivore species. It is reported that these volatiles can induce the defensive responses in plants: an intact plant that is exposed to these volatiles from neighboring infested plants becomes more defensive against herbivores than an unexposed conspecific plant. In this study, we observed induction of defensive response in intact tomato plants against common cutworm (Spodoptera litura) when the intact plants were exposed to the volatiles emitted from tomato plants infested by the caterpillars. We showed that the performance of common cutworm on the exposed intact tomato plants were lower than that on plants exposed to intact plant volatiles (control). We focused on the accumulation of a putative glycoside compound in the exposed plants over the control plants by metabolomic analysis. From these results, we show the intact tomato plants neighboring to herbivore-damaged plants increased their defense against herbivores by changing their metabolism after volatile perception. Now we try to identify the structure and physiological function of this compound.