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

As they develop, many plants deploy shifts in anti-herbivore defense allocation due to changing costs and benefits of their defensive traits. Plant defenses are known to be primed or directly induced by herbivore damage within generations, and across generations by long-lasting epigenetic mechanisms. However, little is known about the ontogenetic trajectories of epigenetically inducible defensive traits across generations and their consequences. To help fill this knowledge gap, we conducted a multigenerational experiment to determine whether defense induction in wild radish plants was reflected in chromatin modifications (DNA methylation); we then examined ontogenetic trajectories (seedlings to reproductive plants) of current and transgenerational plasticity in anti-herbivore chemical (glucosinolates) and physical (trichomes) defenses in this species. Herbivory triggered genome methylation both in targeted plants and their offspring. Within one generation, both defenses were highly indu...