Phenotypic plasticity in plant defense across life stages: Inducibility, transgenerational induction, and transgenerational priming in wild radish

Significance Herbivore attack on plants is known to elicit defensive responses. Such environmentally induced responses can also be expressed by the offspring of attacked plants via DNA methylation—an epigenetic response—but little is known about if and how epigenetic induction varies with plant ontogeny (e.g., seedlings, reproductive plants). Here, we report that herbivory by caterpillars induced changes in the plant epigenome and chemical and physical defenses within and across generations in wild radish. We show that herbivore offense in a plant’s generation affects its progeny’s deployment of defenses throughout its life cycle and that herbivory operates as an important and nuanced driver of phenotypic diversity in plant populations.