Data from: Molecular data and ploidal levels indicate several putative allopolyploidization events in the genus Potentilla (Rosaceae)

Several naturally occurring hybrids in Potentilla (Rosaceae) have been reported, but no molecular evidence has so far been available to test these hypotheses of hybridization. We have compared a nuclear and a chloroplast gene tree to identify topological incongruences that may indicate hybridization events in the genus. Furthermore, the monophyly and phylogenetic position of the proposed segregated genera Argentina, Ivesia and Horkelia have been tested. The systematic signal from the two morphological characters, style- and anther shape, has also been investigated by ancestral state reconstruction, to elucidate how well these characters concur with the results of the molecular phylogenies.
Six major clades, Anserina, Alba, Fragarioides, Reptans, ivesioid and Argentea, have been identified within genus Potentilla. Horkelia, Ivesia and Horkeliella (the ivesioid clade), form a monophyletic group nested within Potentilla. Furthermore, the origin of the proposed segregated genus Argentina (the Anserina clade) is uncertain but not in conflict with a new generic status of the group. We also found style morphology to be an informative character that reflects the phylogenetic relationships within Potentilla. Five well-supported incongruences were found between the nuclear and the chloroplast phylogenies, and three of these involved polyploid taxa. However, further investigations, using low copy molecular markers, are required to infer the phylogeny of these species and to test the hypothesis of hybrid origin.

蔷薇科(Rosaceae)委陵菜属(Potentilla)中已有多个天然杂交种被报道，但迄今尚无分子证据可验证这些杂交起源假说。本研究通过比对核基因树(nuclear gene tree)与叶绿体基因树(chloroplast gene tree)，旨在鉴定该属中可能指示杂交事件的拓扑结构不一致(topological incongruences)现象。此外，本研究还验证了此前提议的分离属(segregated genera)羽衣草属(Argentina)、美国委陵菜属(Ivesia)和胡克丽属(Horkelia)的单系性(monophyly)及其系统发育位置(phylogenetic position)。同时，本研究通过祖先状态重建(ancestral state reconstruction)法，分析了花柱形态与花药形态这两个形态性状的系统发育信号，以阐明这两类性状与分子系统发育研究结果的吻合程度。
研究在委陵菜属内共鉴定出6个主要演化支(clades)：Anserina、Alba、Fragarioides、Reptans、ivesioid以及Argentea。胡克丽属(Horkelia)、美国委陵菜属(Ivesia)与Horkeliella（即ivesioid演化支）构成一个单系群，且嵌套于委陵菜属内部。此外，此前提议的分离属羽衣草属(Argentina，即Anserina演化支)的起源尚不明确，但该类群的独立属地位并未与分子证据相悖。本研究同时发现，花柱形态是可有效反映委陵菜属内系统发育关系的性状。核基因系统发育树与叶绿体基因系统发育树之间共存在5个高支持率的拓扑不一致位点，其中3个涉及多倍体类群(polyploid taxa)。不过，后续需利用低拷贝分子标记(low copy molecular markers)开展进一步研究，以明确这些物种的系统发育关系并验证其杂交起源假说。