Publication Type | J |
Authors | Brandt, R., M. Lomonosova, K. Weising, N. Wagner and H. Freitag |
Title | Phylogeny and biogeography of Suaeda subg. Brezia (Chenopodiaceae/Amaranthaceae) in the Americas |
Source | Plant Systematics and Evolution |
Author Keywords | Suaeda subg. Brezia Molecular phylogeny Hybrids Reticulate evolution Biogeography America ancestral state species trees gene trees plants dispersal evolution phylogeography disjunctions suaedoideae polyploidy |
Abstract | Suaeda subg. Brezia (Chenopodiaceae/Amaranthaceae) comprises similar to 45 halophytic species distributed worldwide along coastlines and in saline inland habitats. Thirteen species are currently accepted from the Americas, but species delimitation is difficult due to the scarcity of distinguishing characters. Little is known yet about phylogenetic relationships and biogeography of American Brezia species. Here, we present molecular phylogenies based on DNA sequence data from the nuclear ribosomal internal transcribed spacer (ITS) and the chloroplast rpl32-trnL intergenic region. Our sampling comprised 157 accessions covering all 13 American Brezia species along with 38 accessions from 16 Eurasian taxa. Phylogenetic trees were generated using parsimony and Bayesian methods. Three monophyletic lineages were discerned in the ITS tree: the Suaeda maritima, S. prostrata and S. corniculata group. Most American species proved to belong to the S. corniculata group. Species boundaries were mostly not recovered or even contradicted by the ITS data, which could be a consequence of low sequence variation in terminal clades and/or reticulate evolution. The rpl32-trnL phylogeny was poorly resolved, with the majority of American species being part of a polytomy with few supported internal nodes. Several incongruities were found between the nuclear and chloroplast tree, revealing at least four instances of hybridization and chloroplast capture between distant lineages. Chromosome counts showed that all American species are polyploid with hexaploidy prevailing. We discuss our results in terms of species relationships, hybridization, polyploidy and biogeography with emphasis on the colonization from NE Asia and Europe, and the subsequent spread and diversification in the Americas. |
Author Address | [Brandt, Ronny; Weising, Kurt; Wagner, Natascha; Freitag, Helmut] Univ Kassel, Inst Biol, Dept Sci, Plant Mol Systemat, D-34132 Kassel, Germany. [Lomonosova, Maria] Russian Acad Sci, Cent Siberian Bot Garden, Herbarium, Novosibirsk 630090, Russia. Weising, K (reprint author), Univ Kassel, Inst Biol, Dept Sci, Plant Mol Systemat, Heinrich Plett Str 40, D-34132 Kassel, Germany. weising@uni-kassel.de |
ISSN | 0378-2697 |
ISBN | 0378-2697 |
Publication Date | Dec |
Year Published | 2015 |
Volume | 301 |
Issue | 10 |
Beginning Page | 2351-2375 |
Digital Object Identifier (DOI) | 10.1007/s00606-015-1233-y |
Unique Article Identifier | WOS:000365449200004 |
Plants associated with this reference |