Rare plant conservation relies on an understanding of the natural history, biology and ecology, and real and potential threats to their populations to inform state regulations that serve to protect the species from extirpation. This work often involves extensive field surveys over several years to determine population sizes and whether those populations are seeing reductions in number of individuals necessary to maintain the genetic diversity within and between those populations. Species and populations with high genetic diversity are better equipped to withstand sudden changes to their habitats that derive from land use changes and changing climate. There are a variety of methods used to investigate population genetic diversity and next generation sequencing (NGS) methods allow for complete genomic coverage by analyzing single nucleotide polymorphisms (SNPs) and allowing for an estimation of population genetic parameters such as genetic variation (FST), the inbreeding coefficient (FIS), and heterozygosity (HO) (HE). Population genomic investigations of Baptisia australis, Chasmanthium latifolium, and Erigenia bulbosa, plant species at the edge of their ranges in Pennsylvania and disjunct distributions within the state were performed for this study. All three species exhibited lower than expected heterozygosity and, with the exception of Chasmanthium, high levels of inbreeding. This information was incorporated into conservation rank status assessments and climate change vulnerability indices using the NatureServe Conservation Status Rank Calculator and the Climate Change Vulnerability Index tools. As a result, state ranks for Chasmanthium and Erigenia require formally proposed changes to the Department of Conservation of Natural Resources. Likewise, management recommendations are given as guidance on the steps likely necessary to preserve and potentially increase the genetic diversity for all species. Through these investigations, a long-term partnership between the Pennsylvania Natural Heritage Program at Western Pennsylvania Conservancy and Bucknell University was developed through which a pipeline of undergraduate and graduate students were, and will be, trained in both field-based natural heritage methods and new, innovative ways address the conservation of rare plants in Pennsylvania and beyond.
Final Report for Grant Agreement WRCP-17571. Western Pennsylvania Conservancy.
• Schuette, S. and C.T. Martine. 2021. Investigation into the Genetic Provenance of Three Rare Plants with East-West Disjunction Patterns in Pennsylvania. Final Report for Grant Agreement WRCP-17571. Western Pennsylvania Conservancy. 33 pp.