Genetic Variation in Tillandsia fasciculata Sw. (Bromeliaceae): Biogeographic and Evolutionary Implications

Few studies have taken a plant population genetics approach to address phylogeographic patterns in the Caribbean, a recognized biodiversity hotspot.  The Tillandsia fasciculata complex, which occurs in and around the entire Caribbean Basin, makes an ideal lineage to address questions of Caribbean plant origins and assemblages.  The T. fasciculata complex consists of eight varieties of that species, 25 additional species, and three natural hybrids.  The aim is to 1) examine genetic variation across the entire range of the T. fasciculata complex, 2) study the direction of gene flow from mainland to islands, island to island, and within islands as it pertains to T. fasciculata; 3) examine genetic structure of these populations in a way that will be useful in assessing conservation priorities.  To test this, we sampled 10-15 individuals per site throughout the Caribbean using microsatellite markers.  For example, when comparing Florida and Bahamian populations, all loci were 100% polymorphic in all populations.  For the Bahamian populations, allele 152 in locus e19 was the most frequent in the Maidenhair population and second most frequent in the Rainbow Blue Hole population, but was not found in either of the Florida populations.  In the PCA, the Bahamian populations clustered together further suggesting genetic differences between mainland (Florida) and island (Bahamas).  Preliminary results from data suggest that Florida and Bahamian populations are genetically distinct.  This project will be the first bromeliad population genetics study focused on comparing islands in the Caribbean to nearby mainland areas.