Plants frequently duplicate their entire genomes, doubling their chromosome number in a process called polyploidization. Remarkably, not only do these polyploids often thrive, but also make significant contributions to the biodiversity of flowering plants. However, because newly formed polyploid lineages suffer a broad range of ecological costs, their ubiquity is puzzling. One possibility, which is evaluated by this research, is that the success of polyploid plants stems from increased resistance to parasites and pathogens. This hypothesis will be tested using mathematical models and field studies of synthetic polyploid plants.
Preliminary mathematical results demonstrate that polyploid plants should be initially more resistant than diploids. Combined with the proposed field studies, this research will investigate how polyploidy shapes pathogen resistance, and may provide a general explanation for the unexpected prevalence of genome duplication within plants. In addition, this research will provide a unique opportunity for an undergraduate student to receive training at the interface of biology and mathematics. This student will participate in both the mathematical modeling and field components of the proposed research, allowing them to see how relevant mathematical theory is developed and then tested in the field. Finally, this research may provide a novel approach to determining the genetic basis of host resistance to pathogens.
