Potter, Kevin M. , Josserand, Sedley , Frampton, John , Nelson, C. Dana .
A Microsatellite Assessment of Genetic Diversity and Gene Flow in Fraser Fir (Abies fraseri), a Southern Appalachian Endemic.
Fraser fir (Abies fraseri) is a coniferous tree species endemic to a handful of the highest ridge systems in the Southern Appalachians of North Carolina, Tennessee and Virginia. These disjunct populations have been isolated since the end of the late-Wisconsin glacial period more than 10,000 years ago. Using microsatellite markers designed specifically for this species, we found a relatively small amount of genetic differentiation among most Fraser fir populations (average FST per locus ≈ 0.04). This may indicate the presence of fairly extensive gene flow among populations, in the form of pollen wind dispersal over long distances (5-60 km), or may suggest that inadequate time has passed to allow for significant genetic separation among the populations. Several results appear to point to the presence of pollen-mediated gene flow between populations, the effect of which decreases as the distance between populations increases: 1) Pairwise FST and genetic distance values showed that populations nearer to each other were generally, but not always, more genetically similar than those more distant. 2) The mean number of alleles per locus was negatively correlated with population isolation. 3) The most isolated population, Mount Rogers in Virginia, was the most genetically differentiated and had the smallest mean number of alleles per microsatellite locus. These results will be useful in the assembly of a gene conservation plan for Fraser fir, which has experienced severe mortality from the infestation of the balsam woolly adelgid (Adelges piceae), an exotic insect from Europe.
Log in to add this item to your schedule
1 - North Carolina State University, Department of Forestry and Environmental Resources, Campus Box 8002, Raleigh, North Carolina, 27965-8002, USA
2 - U.S. Forest Service, Southern Institute of Forest Genetics, Harrison Experimental Forest, 23332 Highway 67, Saucier, Mississippi, 39574
Presentation Type: Oral Paper
Date: Monday, August 15th, 2005
Time: 8:15 AM