Abstract
Plants infested by herbivores emit the special blend of volatiles, including green leaf volatiles different from volatiles emitted from intact plants. The blend of volatiles functions, for instance, as alarm signal for intact plants surrounding infested plants to induce the defensive response against upcoming herbivore attack. To clarify the molecular basis of induced defense, we used tomato plants, Solanum lycopersicum cv. Micro-Tom, and common cutworm, Spodoptera litura, a herbivorous insect of tomato plants, as a model system for volatile-induced defense. Last year, we present the induced defense in the plants exposed to herbivore-infested volatiles against subsequent infestation by common cutworms and the accumulation of glycoside in exposed plants probably related to the defense. In this report, we show the induced defense and glycoside accumulation in intact plants by exposure of only one compound, Z3-hexenol, which is a constituent of the blend of herbivore-infested tomato volatiles. These findings suggest that the Z3-hexenol presumably works as a signal compound emitted from damaged plants to their surrounding intact plants.
