Date: Tuesday, September 26th
Time: 3:30pm
Location: Smith Hall, 359
Title: Population genetics of Oplismenus undulatifolius (wavyleaf basketgrass)
Abstract: Oplismenus undulatifolius (wavyleaf basketgrass) is a relatively new introduction to the mid-Atlantic region. The first known population was found in Patapsco Valley State Park in 1996 and this invasive species has since spread to other locations in Maryland, Virginia and Pennsylvania. This grass is a stoloniferous perennial, spreading locally by vegetative growth and over long distances by the production of unusually sticky seeds that adhere well to fur and clothes. With the first known populations occurring in a heavily visited state park, humans are likely a major pathway of dispersal for O. undulatifolius. The objective of this project was to use microsatellites and SNPs to investigate the genetic diversity among the North American populations of O. undulatifolius. In doing so, we were interested in determining if 1) the North American populations are the result of a single introduction event or multiple separate introductions and 2) the amount of genetic similarity with the native North American congener, Oplismenus hirtellus sp. setarius. If there is enough genetic diversity in the introduced populations, we also wanted to attempt to determine pathways of dispersal between discrete North American populations. To date, we have identified 16 different polymorphic microsatellite loci with 2-5 alleles per locus and examined these in three populations. The population at the site of the initial introduction shows the highest variability while the sites with a shorter history have lower genetic variability and contain different subsets of alleles from each other. This preliminary finding is consistent with separate dispersal events out of the original site.
