Using restriction-site variation of PCR-amplified cpDNA genes for phylogenetic analysis of tribe Cheloneae (Scrophulariaceae)

Data from restriction-site variation of three PCR-amplified chloroplast genic regions (trnK, rps2, and rbcL) were used to assess the utility of PCR-based methodology for phylogenetic reconstruction. Seventeen genera from tribe Cheloneae s.l. (Scrophulariaceae), and one genus each from Solanaceae, Acanthaceae, and Bignoniaceae, representing 32 taxa, were sampled. Phylogenetic reconstruction, based on a combined data set of 138 variable restriction sites, revealed a monophyletic clade of North American Cheloneae, which were not inconsistent with a polyphyletic Scrophulariaceae. Separate analyses of individual genie regions were unable to completely resolve the phylogeny, but were adequate for resolving relationships of major clades among the taxa sampled. We suggest that analysis of PCR-product restriction-site variation is useful for phylogenetic reconstruction above the species level.