Development of single-nucleotide polymorphism markers for Bromus tectorum (Poaceae) from a partially sequenced transcriptome(1)

PREMISE OF THE STUDY: Bromus tectorum (Poaceae) is an annual grass species that is invasive in many areas of the world but most especially in the U.S. Intermountain West. Single-nucleotide polymorphism (SNP) markers were developed for use in investigating the geospatial and ecological diversity of B. tectorum in the Intermountain West to better understand the mechanisms behind its successful invasion. METHODS AND RESULTS: Normalized cDNA libraries from six diverse B. tectorum individuals were pooled and sequenced using 454 sequencing. Ninety-five SNP assays were developed for use on 96.96 arrays with the Fluidigm EP1 genotyping platform. Verification of the 95 SNPs by genotyping 251 individuals from 12 populations is reported, along with amplification data from four related Bromus species. CONCLUSIONS: These SNP markers are polymorphic across populations of B. tectorum, are optimized for high-throughput applications, and may be applicable to other, related Bromus species.