XVI International Botanical Congess

Two non-coding regions of cpDNA were used to examine phylogenetic relationships in the Hamamelidoideae.Sequences of trnL-trnF intergenic spacer and trnL intron were informative in resolving relationships among genera and at higher levels.Three major lineages are identified:the Corylopsis lineage,Trichocladus lineage,and Hamamelis lineage. Corylopsideae,Hamamelideae,and Dicoryphinae are found to be monophyletic,Loropetalinae and Eustigmateae appear to be paraphyletic,and Hamamelideae and Fothergilleae to be polyphyletic.These results are consistent with previous analyses based on nrDNA ITS sequences and the cpDNA matK gene.Morphological characters,such as apetaly,strap-shaped petal,and wind pollination,which have been used to define suprageneric groups,evolved independently in the three lineages.