The more, the better? Stress response in related polyploid ferns

Polyploidy, or whole genome duplication, is common in land plants. Polyploidy causes new gene combinations and is thought to provide an advantage amid the rising temperature and unpredictable precipitation regimes expected under climate change. Using related woodfern species, we investigated the gametophyte physiology of two parent species, Dryopteris intermedia (2n) and Dryopteris expansa (2n) in comparison to their polyploid offspring, Dryopteris campyloptera (4n) . We subjected gametophytes from each species to environmentally stressful heat and drought conditions. Surprisingly, the polyploid did not exhibit a significant physiological advantage or greater resilience to stress compared to the diploid parents.