The Influence of Genome Duplication on Brassicaceae and Rosaceae Community Structure Across the United States.

Many species of agricultural importance are polyploid, having more than two complete chromosome sets. However, it is not clear if ploidy is always associated with traits that may have facilitated the transition of wild species to agriculturally important crops. For example, polyploid species are often thought to be better competitors, either being weedy and invading communities, or being resistant to weedy species.  However, evidence for either of these hypotheses is typically limited to geographically localized studies or only focal species. We combined a phylogenetic framework and continental-scale data on plant communities from the National Ecological Observatory Network (NEON) to test the importance of ploidy and native status in structuring communities of the agriculturally important Brassicaceae and Rosaceae families across the United States. We found that using a dynamic modeling approach can help identify the factors influencing plant communities, and that ploidy influences community composition. These results suggest that polyploid species may sometimes make better agricultural species.