ABSTRACT Rapid movement of individual organs by plants can function as effective defenses against herbivores, yet such responses are energetically costly and may interfere with other important ecological functions. Therefore, plants must balance the risks of responding to unreliable cues with the costs of failing to defend against attack. Here, we investigated whether prior herbivory experience modulates contact‐induced defensive floral closure in Drosera spatulata . This species closes its flowers within minutes of mechanical contact, thereby protecting its ovules from a specialist herbivore, Buckleria paludum caterpillar. Because the caterpillars first feed on leaves and later shift to flowers in a few days, leaf damage may provide predictive information about future florivory risk. To test whether the plant integrates herbivory information across organs, we experimentally simulated leaf herbivory prior to flowering and applied standardized contact stimuli to flowers. Plants with prior leaf damage closed their flowers at significantly tighter angles within 15 min than controls. These results show that D. spatulata adjusts the intensity of defensive movement by integrating past herbivory experience with ambiguous contact cues, demonstrating cross‐organ priming in a plant movement defense. Our findings suggest that past experience serves as a broader source of information that plants use to support their context‐dependent behavior.
Tagawa et al. (Thu,) studied this question.