TreeBASE Search-Matrices for study 10386

@ARTICLE{TreeBASE2Ref18858, author = {David L. Boose and Steven Harrison and Suzette Clement and Susan Meyer}, title = {Population genetic structure of the seed pathogen Pyrenophora semeniperda on Bromus tectorum in western North America}, year = {2010}, keywords = {Analysis of Molecular Variance (AMOVA), ascomycete, Drechslera campanulata, genetic diversity, internal transcribed spacer (ITS), invasive species, ribosomal RNA}, doi = {}, url = {http://}, pmid = {}, journal = {Mycologia}, volume = {}, number = {}, pages = {}, abstract = {We examined genetic variation in the ascomycete pathogen Pyrenophora semeniperda cultured from seeds of the invasive grass Bromus tectorum in the Intermountain West of North America. We sequenced the internal transcribed spacer (ITS) region of the nuclear ribosomal RNA genome in 417 monoconidial cultures collected from 20 sites in Washington, Idaho, Utah, and Colorado, USA. ITS sequence diversity was surprisingly high; 12 unique haplotypes were identified, averaging 1.3% pairwise sequence divergence. All sites had at least two haplotypes present, and three sites had seven or more. One haplotype comprised 60% of the isolates and occurred at all 20 locations; the remaining haplotypes generally occurred at low frequencies within sites, but at multiple sites throughout the region. Sites in Washington and Idaho were more diverse than those in Utah and Colorado, averaging 2 more haplotypes and 67% more pairwise differences among haplotypes at a site. Analysis of Molecular Variance (AMOVA) indicated that more than 80% of the genetic variation is found within sampling locations, while 7 ? 11% of the variation can be attributed to differences between northern (Washington and Idaho) and southern (Utah and Colorado) populations. The wide distribution of even uncommon haplotypes among sampling sites, and weak correlations between genetic and geographic distances among populations (< 0.2), suggest that these populations were recently established from a common source. We hypothesize that the strains of P. semeniperda infecting B. tectorum in western North America probably arrived with the invasive grass from its native Eurasian range. } }