PARENT SESSION
Tuesday, August 8, 5:00-6:30 pm
Poster Session 10 - Genetics, evolution, and paleoecology
Exhibit Hall, Ballroom Level, Cook Convention Center

Genetic variability of the rare cedar glade endemic Astragalus bibullatus: comparing estimates based on AFLP markers and isozymes.

Baskauf, Carol^*,1, Burke, John², ¹ Austin Peay State University, Clarksville, TN² Vanderbilt University, Nashville, TN

ABSTRACT- AFLP markers were used to investigate the population genetics of the endangered plant Astragalus bibullatus (Fabaceae) which is endemic to limestone cedar glades in Tennessee. Populations of this species are genetically very similar, with genetic identity values ranging from 0.975 to 0.991. The FST estimate indicates that about 10% of the total genetic variability of the species is due to differences among the seven sites sampled. Averaging across populations, about 38% of the AFLP markers are polymorphic, and mean expected heterozygosity is estimated to be 0.116. These estimates based on AFLP markers are compared with an earlier isozyme study of this same species in which populations were also found to be genetically similar to each other (genetic identities of 0.981 to 1.000, F_ST of 9%) but for which genetic variability estimates were lower (25.6% polymorphic loci, 0.063 for expected heterozygosity) .

Key words: population genetics, aflp, astragalus bibullatus