Polyploidy and plant resilience to environmental stresses: Molecular mechanisms and future applications

Polyploidy, the condition of possessing more than two sets of chromosomes, is prevalent across the tree of life, particularly in green plants (Viridiplantae). It plays a crucial role in plant evolution, speciation, and adaptation. This review explores the intricate relationship between polyploidy and plant interactions with environmental stresses, focusing on recent studies that demonstrate how polyploid plants often exhibit enhanced stress tolerance compared to related diploids, including various biochemical and physiological responses. We also review the role of epigenetic modifications in diploid versus polyploid responses to stress. The genetic redundancy afforded by polyploidy often results in the up-regulation of stress-responsive genes and pathways, as well as neofunctionalization. Additionally, we highlight multi-omics approaches, comparing polyploids and their diploid progenitors with emphasis on the complex interactions between ploidy and stress responses. These recent results collectively enhance our understanding of how polyploid plants, including crops, rewire metabolic pathways and protein networks, thereby optimizing their survival in challenging environments. This improved knowledge of polyploids and their stress responses is essential for understanding the success of polyploid plants in nature, as well as future practical research applications; harnessing polyploid traits through breeding programs could enhance crop resilience and promote sustainable agriculture. We propose key areas for further investigation, emphasizing the potential of traits in polyploid plants for mitigating the impacts of altered climatic conditions on global food security.