Lindqvist Charlotte, De Laet Jan, Haynes Robert R, Aagesen Lone, Keener Brian R, Albert Victor A
Natural History Museum, University of Oslo, PO Box 1172 Blindern, 0318 Oslo, Norway.
Leuvenstraat 20, B-3020 Veltem-Beisem, Belgium.
Cladistics. 2006 Dec;22(6):568-588. doi: 10.1111/j.1096-0031.2006.00124.x.
Like most aquatic plants, the pondweeds (Potamogetonaceae) are among the most phenotypically reduced and plastic of all angiosperms. As such, hypotheses of structural homology present difficulties for morphological phylogenetic reconstruction. We used non-coding nuclear and plastid DNA data to address Potamogetonaceae relationships and accompanying issues in character evolution and biogeography. Genera currently assigned to Potamogetonaceae, plus Zannichellia, formed a strongly supported monophyletic group. Potamogeton and Stuckenia (Potamogeton subg. Coleogeton) were both resolved as monophyletic. Within Potamogeton proper, two major clades followed the traditional split between broad- and narrow-leaved species, with the latter condition optimized as basal. Heterophylly (submerged plus floating leaves) has evolved several times, and the ancestral distribution for Potamogeton appears to be Northern Hemispheric. Our phylogenetic results have provided a useful genetic framework from which to interpret morphological, cytological and biogeographical evolution.
与大多数水生植物一样，眼子菜科植物是所有被子植物中表型简化程度最高且可塑性最强的植物之一。因此，结构同源性假说给形态系统发育重建带来了困难。我们使用非编码核DNA和质体DNA数据来研究眼子菜科的亲缘关系以及伴随的性状演化和生物地理学问题。目前归入眼子菜科的属，加上角果藻属，形成了一个得到有力支持的单系类群。眼子菜属和茨藻眼子菜属（眼子菜亚属Coleogeton）均被解析为单系类群。在狭义的眼子菜属内，两个主要分支遵循了阔叶和窄叶物种之间的传统划分，窄叶状态被优化为基部状态。异形叶性（沉水叶加浮水叶）已经多次进化，眼子菜属的祖先分布似乎在北半球。我们的系统发育结果提供了一个有用的遗传框架，可据此解释形态学、细胞学和生物地理学的演化。
