Systematics Section / ASPT
Ball, Peter W. , Kadereit, Gudrun .
Salicornia and Sarcocornia in North America: problems of incongruity between molecular phylogeny and morphology.
The treatment of Salicornia and Sarcocornia in Flora North America (Ball, 2003) was based mainly on dried specimens. The systematics of these genera is problematic because of the highly reduced morphology and succulence of the plants. Investigations utilizing nuclear rDNA ETS sequences has resulted in a phylogeny which addresses some problems, but creates others.
Salicornia maritima (diploid) is identical to European diploids based on ETS sequences but is distinct morphologically. Accessions of the tetraploids S. depressa and S. bigelovii form distinct clades with only a weakly supported sister group relationship and further relationships are unclear. A third tetraploid group from E. Canada seems to be closely related to Eurasian populations. Salicornia bigelovii is morphologically distinct, but S. depressa is difficult to separate from Eurasian populations and from the E. Canadian plants. Salicornia borealis is identical to some accessions of S. rubra on ETS data, but the monophyly of the latter still needs to be shown.
In Sarcocornia the distinctness of S. utahensis is confirmed by ETS data, but S. pacifica (sensu Ball, 2003) separates into 2 clades S. pacifica (Pacific coast) and S. ambigua (Atlantic coast)which can be distinguished morphologically by seed size.Sarcocornia perennis (Pacific northwest) is identical to S. pacifica in ETS sequences, but can be distinguished morphologically, although there may be a north-south cline from S. perennis to S. pacifica. ETS sequence data place S. perennis(North America) and S. perennis (Eurasia)in different clades of Sarcocornia, but no morphological differences have been demonstrated. A revised account of Salicornia and Sarcocornia in North America will be available.
Log in to add this item to your schedule
1 - University of Toronto, Botany Department, Erindale College, Mississauga, Ontario, L5L 1C6, Canada
2 - Universitat Mainz, Institut fur Spezielle Botanik, Mainz, 55099 Mainz, Germany
Presentation Type: Poster:Posters for Sections
Location: Exhibit Hall (Northeast, Southwest & Southeast)/Hilton
Date: Sunday, July 8th, 2007
Time: 8:00 AM