Microsatellite primers in Agave utahensis (Asparagaceae), a keystone species in the Mojave Desert and Colorado Plateau(1)

• Premise of the study: Utah agave (Agave utahensis) and its putative subspecies, A. utahensis subsp. kaibabensis and A. utahensis subsp. utahensis, are keystone species of the Mojave Desert and Colorado Plateau in the southwestern United States. Here we developed microsatellite markers to study population structure and genetic diversity of the two subspecies of A. utahensis. • Methods and Results: We analyzed 22,386 454-pyrosequencing large contigs (>400 bp), derived from a genome reduction experiment consisting of A. utahensis accessions, for putative microsatellites. The use of unique multiplex barcodes for each of the Agave accessions allowed for the identification of putatively polymorphic microsatellites based solely on sequence alignment analysis. We report the characteristics of 11 polymorphic microsatellite loci based on a panel of 104 individuals from the two subspecies. The number of alleles per locus varied from three to eight, with an average of 5.5 alleles per locus. Observed and expected heterozygosity values ranged from 0.038 to 0.777 and 0.038 to 0.707, respectively. • Conclusions: The microsatellites identified here will be invaluable for future studies of population structure, polyploidy, and genetic diversity across the species.