Plasticity in ploidy underlies plant fitness compensation to herbivore damage

How plants mitigate damage by animal herbivores is a fundamental ecological and evolutionary question of plant-animal interactions. Some plants can increase their fitness when damaged in a phenomenon termed “overcompensation.” Despite overcompensation being observed in a variety of plant species, its mechanistic basis remains elusive. Recent research has shown that the Arabidopsis thaliana genotype Columbia-4 employs endoreduplication, the replication of the genome without mitosis, following damage and that it overcompensates for seed yield. The related genotype Landsberg erecta, in contrast, does not increase its endoreduplication following damage and suffers reduced seed yield. While these results suggest that a plant's ability to plastically increase its ploidy during regrowth may promote its mitigation of damage, no studies have explicitly linked the endoreduplication genetic pathway to the regrowth and fitness of damaged plants. By comparing fitness and ploidy between undamaged and...