Abstract Detail

Systematics

Barbera Sanchez, Patricia [1], Peterson, Paul M. [2], Romaschenko, Konstantin [3], Soreng, Robert J. [3], Quintanar Sanchez, Alejandro [4], Aedo Perez, Carlos [5], Saarela, Jeffery M. [6].

A molecular phylogeny of the Aveneae-type plastid DNA clade (Poaceae: Pooideae: Poeae).

In the most recent grass classification, the Aveneae-type plastid DNA clade contains 39 genera and 1039 species in the following seven subtribes: Agrostidinae (604 species in 16 genera), Anthoxanthinae (69 species in a single genus), Aveninae (302 species in 15 genera), Brizinae (5 species in 2 genera), Calothecinae (26 species in 2 genera), Phalaridinae (17 species in a single genus), and Torreyochloinae (16 species in 2 genera). Earlier molecular analyses using plastid trnL-F and ITS DNA sequences indicated that generic limits among the core Agrostidinae are not well understood and species of Calamagrostis and Trisetum formed two separate clades, one composed of Old World species and the other of New World species. We conducted a phylogenetic analysis of 61 genera and 550 species (53%, 1280 samples) in the Aveneae-type plastid clade using sequence data from three plastid regions (rpl32-trnL spacer, rps16-trnK spacer, and rps16 intron) and nuclear ribosomal internal transcribed spacer regions (ITS 1 & 2) to infer evolutionary relationships among these species. Calamagrostis, Helictotrichon, Koeleria, Trisetaria, and Trisetum are polyphyletic genera with species occurring in three or more clades. Our plastid phylogeny includes two clades (a northern and southern hemisphere) of many species of Calamagrostis with species of Ammophila, Graphephorum, Peyritschia, Sphenopholis, Trisetopsis, and Trisetum embedded. Trisetum s.s., with only a few species, is sister to Rostraria. Deschampsia (Poeae-type plastid DNA clade) appears paraphyletic with some South American species of Calamagrostis (subsect. Stylagrostis) embedded. Anthoxanthum, Arrhenatherum, Avena, Lagurus, Phalaris, Rostraria, and Torreyochloa appear monophyletic. Agrostis appears monophyletic with Lachnagrostis and Polypogon embedded in the plastid tree. However, in the ITS-derived tree, Lachnagrostis and Polypogon are embedded in much smaller northern hemisphere Calamagrostis clade. Overall the plastid and nuclear ITS-derived trees are mostly congruent except for relationships among species of Calamagrostis, Koeleria, and Trisetum where significant gene flow has occurred, probably in the deeper past.

1 - Real Jardin Botanico de Madrid, Biodiversidad y Conservacion, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, 28014, Spain
2 - Smithsonian Institution, Botany, MRC-166 National Museum of Natural History, PO Box 37012, Washington, DC, 20013-7012
3 - Smithsonian Institution, Botany, MRC-166 National Museum of Natural History, PO Box 37012, Washington, DC, 20013-7012, USA
4 - Rreal Jardin Botanico de Madrid, Biodiversidad y Conservacion, Consejo Superior de Investigaciones Cientificas (CSIC), Madrid, 28014, Spain
5 - Real Jardin Botanico de Madrid, Biodiversidad y Conservacion, Consejo Superior de Investigaciones Cietificas (CSIC), Madrid, 28014, Spain
6 - Canadian Museum of Nature, Botany, Ottawa, ON, K1P 6P4, Canada

Keywords:
Agrostis
Calamagrostis
classification
Koeleria
ITS
Plastid DNA sequences
systematic
Trisetum.

Presentation Type: Oral Paper
Session: 45, Monocots part B/Basal Eudicots
Location: 200/Savannah International Trade and Convention Center
Date: Wednesday, August 3rd, 2016
Time: 2:15 PM
Number: 45004
Abstract ID:308
Candidate for Awards:None