OESTREICH, ANDREA*, LINDA A RAUBESON, MARY E COSNER, AND ROBERT K JANSEN. Department of Biological Sciences, Central Washington University, Ellensburg, WA 98926 and Section of Integrative Biology, University of Texas, Austin, TX 78713. - Campanulaceae systematics based on four chloroplast DNA markers.
We have completed an analysis of 18 genera of Campanulaceae sensu
stricto based on nucleotide sequences from the chloroplast genes,
rbcL and atpB, and on chloroplast genome structural
mutations. The combined analyses generate a well-resolved and
supported tree that has several interesting biogeographic
implications. For example, the topology of the tree supports an Asian
rather than a Southern Hemisphere origin of the family. The three
Asian genera sampled, Codonopsis, Cyanathus and
Platycodon, occur in a basal position in the tree whereas the
Southern Hemisphere genera form a strongly supported derived clade.
Also, Musschia, a Macronesian endemic, is linked to the
Southern Hemisphere taxa. In terms of phylogenetic implications, the
cpDNA tree corresponds well with the distribution of two major pollen
types in the Campanulaceae but corresponds poorly with previous
suggestions of intrafamilial relationships. Although major
intrafamilial patterns are well supported, the relationships among the
north temperate genera remain unresolved with the current cpDNA data.
Therefore, we are adding data from a third chloroplast gene,
matK. We will analyze all four data sets together to further
resolve our phylogenetic hypotheses.
Key words: atpB, Campanulaceae, genome structure, matK, rbcL