Submitted to: Botanical Journal of the Linnean Society
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 3/20/2007
Publication Date: 6/20/2007
Citation: Lohne, C., Borsch, T., Wiersema, J.H. 2007. Phylogenetic analysis of Nymphaeales using fast-evolving and non-coding chloroplast markers. Botanical Journal of the Linnean Society. 154:141-163.
Interpretive Summary: Water-lilies are a group of beautiful aquatic plants, forming the centerpiece of many aquatic gardens. These plants are important not only as ornamentals but also because this plant group is one of the earliest branches in the tree of flowering plants. The current understanding about how water-lilies are related to each other was based on a DNA study with only a few species. In this study many more kinds of plants were included and relationships among water-lilies has been more accurately determined. These results are important because they expand our knowledge about the earliest flowering plants on earth. In addition, these results will allow plant breeders to develop more beautiful cultivars of water lilies for aquatic gardens.
Technical Abstract: The Nymphaeales (water-lilies and relatives) represent one of the earliest branching lineages of angiosperms and comprise about 70 aquatic species. Here we present a comprehensive study of phylogenetic relationships within Nymphaeales from a data set containing 24 representatives of Nymphaeales, including all currently recognized genera and all subgenera of the genus Nymphaea, plus 5 outgroup taxa. Nine different regions of the chloroplast genome—comprising spacers, group II introns, a group I intron, and a protein coding gene—were analysed. This resulted in a character matrix of 6597 positions and an additional 369 characters obtained from coded length mutations. Maximum parsimony and Bayesian analyses of the complete data set resulted in a single fully resolved, well-supported tree. Our data confirm the monophyly of the Cabombaceae but do not provide convincing support for the monophyly of Nymphaeaceae with respect to Nuphar. Moreover, the genus Nymphaea is inferred to be paraphyletic with respect to Ondinea, Victoria and Euryale. In fact, the Australian endemic Ondinea forms a highly supported clade with members of the Australian Nymphaea subg. Anecphya. In addition, Victoria and Euryale are inferred to be closely related to a clade comprising all night-blooming water-lilies (Nymphaea subgenera Hydrocallis and Lotos).