Conservation genetics of the endangered Apalachicola Rosemary, Conradina glabra.

Lauren Eserman, Atlanta Botanical Garden

Conradina glabra, or Apalachicola rosemary, is a federally listed endangered species that exists only on a small area of sandhill in Liberty County, Florida. Forestry practices in the last 100 years have resulted in declining populations of C. glabra. In the wild, plants produce very few seeds, but small plants that resemble seedlings are commonly found. Through a grant from the US Fish and Wildlife Service, we are using molecular genetic techniques to understand whether C. glabra is reproducing clonally or via sexual reproduction as well as what factors encourage seed germination. To address this question, we sampled plants from forty locations across Torreya State Park in a spatially explicit experimental design. A plant in the center of a large cluster of individuals was marked and samples were taken from plants in all four cardinal directions from the central plant at designated distances. From these samples, we generated RADseq data resulting in >10,000 SNPs from 564 individual plants. Analyses are still ongoing, but early results point to spatially structured genetic variation. Individuals share highly similar genotypes at distances < 1 meter; however, are genetically distinct at distances greater than 1 meter. These results suggest that Conradina glabra is perhaps clonal at very small geographic scales but is generally reproducing sexually across its range. Furthermore, we identify areas with unique genetic variation that is important for conservation. The results of this study are being communicated to land managers who are tasked with preserving this species on the ground.