title: Geographic distribution of genetic variation among native and introduced populations of Chinese tallow tree, Triadica sebifera (Euphorbiaceae).
abstract: OBJECTIVE
  Invasive plants often display genetically determined variation in patterns of growth and resource allocation between native and introduced genotypes, as well as among genotypes within different regions of the introduced range. We examined patterns of genetic variation within and among native and introduced populations of the tetraploid Chinese tallow tree (Triadica sebifera, Euphorbiaceae) to determine whether nonselective evolutionary processes or the introduction history could contribute to previously observed phenotypic differences between native and introduced populations as well as among introduced populations.
  
  
  METHODS
  We used six microsatellite markers to study 12 native populations in China, 51 introduced populations in the southeastern USA, and one introduced population in Australia.
  
  
  RESULTS
  Genetic diversity was greater within and among native populations than introduced populations. Within the southeastern USA, populations in Georgia and South Carolina differed substantially in their genetic composition and had greater genetic diversity than the rest of the southeastern USA. Greater genetic similarity between some populations in the native range and introduced range indicate a common provenance for Georgia and South Carolina populations that could have come from any of several western or southern Chinese populations and a different provenance for other southeastern USA populations and the Australian population, which were most similar to more northeastern Chinese populations.
  
  
  CONCLUSIONS
  Differences among introduced populations in potentially adaptive traits (e.g., herbivore tolerance, herbivore resistance, growth rates) may result in part from the introduction history, in particular from differences present among source populations in the native range.
authors: Department of Biological Sciences, Clemson University, Clemson, South Carolina 29634, USA. saarad@clemson.edu
authors: Saara J
authors: SJ
authors: DeWalt
authors: Evan
authors: E
authors: Siemann
authors: William E
authors: WE
authors: Rogers
mesh_terms: D000483:Alleles; D001499:Bayes Theorem; D056426:Genetic Loci / Q000235:genetics; D014644:Genetic Variation; D005828:Genetics, Population; D005838:Genotype; D005843:Geography; D058865:Introduced Species; D018895:Microsatellite Repeats / Q000235:genetics; D011157:Population Dynamics; D018401:Sample Size; D031287:Sapium / Q000235:genetics* / Q000254:growth & development*; D015144:Southeastern United States