Revisiting the phylogeny of Dipsacales: New insights from phylogenomic analyses of complete plastomic sequences

Phylogenetic relationships in Dipsacales have long been a major challenge. Although considerable progress has been made during the past two decades, questions remain; the uncertain systematic positions of Heptacodium, Triplostegia, and Zabelia, in particular, impede our understanding of Dipsacales evolution. Here we use 75 complete plastomic sequences to reconstruct the phylogeny of Dipsacales, of which 28 were newly generated. Two primary clades were recovered that form the phylogenetic backbone of Dipsacales. Seven of the primary clades correspond to the recognized families Adoxaceae, Caprifoliaceae s. str., Diervillaceae, Dipsacaceae, Linnaeaceae, Morinaceae, and Valerianaceae, and one corresponds to Zabelia, which was found to be the closest relative of Morinaceae in all analyses. Additionally, our results, with greatly increased confidence in most branches, show that Heptacodium and Triplostegia are members of Caprifoliaceae s. str. and Dipsacaceae, respectively. The results of our study indicate that the complete plastomic sequences provide a fully‐resolved and well‐supported representation of the phylogenetic relationships within Dipsacales.     

A phylogenetic analysis of 100+ genera and 50+ families of euasterids based on morphological and molecular data with notes on possible higher level morphological synapomorphies

 A data matrix of 143 morphological and chemical characters for 142 genera of euasterids according to the APG system was compiled and complemented with rbcL and ndhF sequences for most of the genera. The data were subjected to parsimony analysis and support was assessed by bootstrapping. Strict consensus trees from analyses of morphology alone and morphology + rbcL + ndhF are presented. The morphological data recover several groups supported by molecular data but at the level of orders and above relationships are only superficially in agreement with molecular studies. The analyses provide support for monophyly of Gentianales, Aquifoliales, Apiales, Asterales, and Dipsacales. All data indicate that Adoxaceae are closely related to Dipsacales and hence they should be included in that order. The trees were used to assess some possible morphological synapomorphies for euasterids I and II and for the orders of the APG system. Euasterids I are generally characterised by opposite leaves, entire leaf margins, hypogynous flowers, “early sympetaly” with a ring-shaped corolla primordium, fusion of stamen filaments with the corolla tube, and capsular fruits. Euasterids II often have alternate leaves, serrate-dentate leaf margins, epigynous flowers, “late sympetaly” with distinct petal primordia, free stamen filaments, and indehiscent fruits. It is unclear which of these characters represent synapomorphies and symplesiomorphies for the two groups, respectively, and there are numerous expections to be interpreted as reversals and parallelisms. Received August 28, 2000 Accepted August 7, 2001     

五福花科花部维管结构的比较研究

首次报道了华福花属华福花Ｓｉｎａｄｏｘａｃｏｒｙｄａｌｉｆｏｌｉａ和东方五福花Ａｄｏｘａｏｒｉｅｎｔａｌｉｓ花部维管结构,并对五福花科３属４种植物的花部维管系统进行了比较研究。３属４种的花部维管系统表现出不同的对称性和不同的复化、减化以及不同的融合程度。基于花部维管系统的证据,本工作支持四福花属四福花Ｔｅｔｒａｄｏｘａｏｍｅｉｅｎｓｉｓ为科内原始类群代表的看法。     

Molecular Phylogeny and Species Speciation of Adoxaceae. s. s

It remains unclear about the speciation and phylogeny of Adoxaceae s. s ., a small family with 3 genera and 4 species . In this paper , ITS ( nuclear DNA internal transcribed spacer) regions of Adoxa orientalis and Sambucus adnata were firstly sequenced . Phylogenetic trees were constructed for all species of Adoxaceae (four species ) , Sambucus, Viburnum and four genera of Caprifoliaceae . The divergences among four species of this family were further calculated based on the calibration of the fossil records of the Caprifoliaceae and the general evolutionary rate of herbs for ITS . The phylogenetic analyses did not support the previous assumptions on the phylogeny and species divergence of Adoxaceae s. s . based on the morphological evidence : Tetradoxa is not the firstly diverged and it clustered with two species of Adoxa as a monophylogenetic group , paralleling to the other lineage comprising of monotypic Sinadoxa . The allopatric speciation at the diploid level might have contributed to the differentiation among Sinadoxa corydalifolia, Tetradoxa omeiensis and Adoxa moschatellina and the polyploidy to the origin of A. orientalis . The crude timing based on ITS sequence differentiation suggested a recent divergence among all four species probably between the late Miocene and the Tertiary and this speciation process might be closely correlated with habitat fragmentation and change due to the extensive uplifts of the Qinghai-Tibetan Plateau and climatic oscillation during the glacial and interglacial ages occurred at this stage .     

狭义五福花科的分子系统学和物种分化

狭义五福花科(Adoxaceae.s.s)仅含3属4种,但该科的物种分化、系统发育和分类一直存在争议。本文通过测定东方五福花和血满草的ITS(核糖体DNA内转录间隔区)序列,构建了包括狭义五福花科(4种)、广义忍冬科接骨木属、荚属以及其余4属植物在内的系统发育树。研究结果不支持狭义五福花科内根据形态学证据做出的系统发育假设四福花不是该科中最早分化出来的种;该物种与五福花属的两个物种形成一个单系群,与另一分支华福花属相对应。该科中3个物种,四福花、五福花和华福花之间的分化主要是在二倍体水平上的异域分化,而东方五福花则是通过多倍化形成的。粗略的时间估算表明这些物种之间的分化较晚,可能在第三纪末至第四纪早中期,与青池高原近期强烈隆升以及冰期气候反复变化形成的环境变迁密切相关。