从叶绿体DNA trnL-F序列论双参属的归属问题

双参属Triplostegia Wall．ex DC．由分布于东南亚地区的2个种组成，为多年生草本植物。它的归属一直存在争议，有时置于川续断科Dipsacaceae或败酱科Valerianaceae，有时单立一科，即双参科Triplostegiaceae。本研究对广义川续断目Dipsacales s．l．的21种植物(分别来自于败酱科、川续断科、双参属、刺参属Morina、广义忍冬科Caprifoliaceae s. l．、五福花科 Adoxaceae)和外类群人参Panax schin-seng Nees．的叶绿体 DNA trnL-F区进行了测序，并建立系统发育树状图。结果显示，败酱科、川续断科、双参属、刺参属和广义忍冬科的4个属(双盾木属Dipelta、虫胃实属Kolkwitzia、六道木属Abelia和北极花属Linnaea)形成 了一个单系群并得到了很强的支持(100％ bootstrap)；双参属与川续断科有更近的关系，建议作为一个亚科置于川续断科；广义忍冬科为一多系类群；而刺参属与其他广义川续断目类群之间的关系尚不能确定。

Phylogenetic relationships of the disputed genus Triplostegia based on trnL-F sequences

The phylogenetic relationships of Triplostegia Wall. ex DC., comprising two species of perennial herbs from southeastern Asia, have long been in dispute. This genus was placed in either Dipsacaceae or Valerianaceae or in a family of its own, Triplostegiaceae. In this paper, the chloroplast DNA (cpDNA) trnL F regions of 21 species in the Dipsacales s.l. (including Valerianaceae, Dipsacaceae, Triplostegia, Morina, Caprifoliaceae s.l. and Adoxaceae) and an outgroup Panax schin seng Nees. were amplified and sequenced. The phylogenetic relationships among these 22 species were constructed based on trnL F sequences. The results demonstrated that Valerianaceae, Dipsacaceae, Triplostegia, Morina and four genera from the Caprifoliaceae s.l. form a monophyletic group with a strong support (100% bootstrap). Triplostegia, a sister group to Dipsacaceae, is close enough to be placed in the Dipsacaceae as a subfamily. The traditional Caprifoliaceae s.l. are polyphyletic, and relationships of Morina among the groups within Dipsacales s.l. are uncertain.