Genetic Diversity and Population Structure of the Forgotten Geum, Geum geniculatum Michx.


Marietta Day Shattelroe

Additional Authors:

Page Mangum, Jennifer Rhode Ward, and Matt C. Estep


Dec – 2020


conservation management, federal species of concern, genetic diversity, Geum geniculatum, southern Appalachians

Geum geniculatum (Rosaceae), bent avens, is a perennial herb restricted to the high elevations of three mountaintops near the North Carolina/Tennessee border (USA). Although geographically restricted, occurrences on these mountaintops can have up to hundreds and occasionally thousands of individuals. While Geum geniculatum has been censused thoroughly, some sites have not been visited in over a decade, and formal biological studies are lacking. To understand genetic variation within the species and connectivity among populations, individuals were sampled from each of three extant mountain locations and were genotyped using 14 microsatellite markers previously developed for other congeners. Results show that G. geniculatum displays high genetic diversity, and that each mountain acts as a highly structured metapopulation with moderate interpopulation differentiation. Based on the high numbers of private alleles and results of an M-ratio test, genetic drift is likely driving structure and differentiation among metapopulations. Results will inform management of the species, and suggest that transfer of seeds or genetic material among sites should be minimized.