根据ITS序列证据重建防己科蝙蝠葛族的系统发育

研究了国产防己科蝙蝠葛族tirb．Menispermeae9属20种和外类群青牛胆族trib．Tinosporeae 2属3种植物完整的ITS(包括5.8S rDNA)序列。trib．Menispermeae的ITS长527～601 bp,排序后长667bp。当gap处理为missing时具281个有信息位点。PAUP软件分析结果表明：①trib．Menispermeae是一个单系类群,该分支得到hootstrap l00％的支持;②确定了存疑种Pachygone valida的系统学位置,该种是Coc—culus属的成员;③Sinomenium和Menispermum两属有很近的系统学关系,组成族内稳定的一支,它们的ITS序列同源性极高,ITS1比族内其它属长41～73bp;④Stephania和Cyclea也是系统发育关系很近的两个类群。前者具两个主要分支,其IIS1、ITS2的G+C含量差异较大,在种类组成上,该两大支与传统上Stephania属内处理的2个亚属——千金藤亚属subgen．Stephania和山乌龟亚属subgen．Tuberiphania基本一致;Cyclea属内种间的ITS序列差异小,同源性极高。     

Phylogeny of the tribe Menispermeae (Menispermaceae) reconstructed by ITS sequence data

The phylogeny of the tribe Menispermeae (Menispermaceae) represented by 20 species of 9 genera in China, was reconstructed based on sequence analysis of the internal transcribed spacers (ITS) (including ITS1, ITS2, and 5.8S rRNA gene ) of nuclear ribosomal DNA. Three species of two genera in the tribe Tinosporeae were designated as outgroups. Direct PCR sequencing method was used in the study, The sizes of ITS within trib. Menispermeae range from 527 to 601 bp. The aligned length is 667 bp, which provides 281 phylogenetically informative sites when gaps are treated as missing. The results of phylogenetic analyses show that: ① trib. Menispermeae is a monophyletic group strongly supported by a bootstrap value of 100%; ② Pachygone valida, whose systematic position was uncertain in the previous classification, should be placed in the Cocculus. ③Sinomenium and Menispermum are two close genera of the tribe. Their sequcences are very similar to each other, with ITS1 having 41 to 73 bp longer than that of the other genera in trib. Menispermeae. ④ Stephania and Cyclea are also closely related. The former forms two major clades, which are approximately consistent with the two traditional subgenera: subgen. Stephania and subgen. Tuberiphania. The species of Cyclea are mutually little diverged in complete ITS sequences, and they com-prise a sister clade to the genus Stephania.     

Phylogeny of the tribe Antirrhineae (Scrophulariaceae) based on morphological andndhF sequence data

Phylogenetic relationships within the tribe Antirrhineae (Scrophulariaceae) are analysed and discussed on the basis of parsimony analyses of morphological andndhF gene sequence data. The results indicate that the tribe Antirrhineae consists of four major groups of genera, theAnarrhinum clade, theGambelia clade, theMaurandya clade, and theAntirrhinum clade. TheAnarrhinum clade, consisting of the Old World bee-pollinated generaAnarrhinum andKickxia, is sister to the rest of the tribe. TheGambelia clade consists of the New World generaGambelia andGalvezia, which are very closely related and pollinated by hummingbirds. TheMaurandya clade consists of one subclade includingMaurandya and a number of related bee- or hummingbird-pollinated New World genera and another subclade with the Old World bee-pollinated generaAsarina andCymbalaria. TheAntirrhinum clade consists mainly of bee-pollinated Old World genera, such asAntirrhinum, Linaria, Chaenorhinum, and their segregates, but also includes the New World generaMohavea andHowelliella, of which the latter is known to be partly pollinated by hummingbirds. It is concluded that hummingbirdpollination has evolved independently within Antirrhineae at least three times from bee-pollinated ancestors.     

Phylogenetic studies in the Gerbera-complex (Compositae, tribe Mutisieae, subtribe Mutisiinae)

The phylogeny of the Gerbera-complex (Compositae, tribe Mutisieae, subtribe Mutisiinae) is discussed with the use of cladistics. 14 OTUs are accepted, viz. 1. Trichocline s. str., 2. Lulia , 3. Trichocline spathulata ("Amblysperma") , 4. Gerbera hieracioides, 5. Chaptalia , 6. Leibnitzia , 7. Uechtritzia , 8. Perdicium , 9. Gerbera sect. Gerbera , 10. Gerbera sect. Parva , 11. Gerbera sect. Lasiopus , 12. Gerbera sect. Piloselloides , 13. Gerbera sect. Pseudoseris , and 14. Gerbera sect. Isanthus. The work is mainly based on SEM-studies. The paper discusses the phylogenetic and taxonomic implications of the presented consensus-tree. It is proposed to rank the Gerbera-complex as a single, large genus.     

The phylogeny of Gaura (Onagraceae) based on ITS, ETS, and trnL-F sequence data

Gaura (Onagraceae: Onagreae) is a small North American genus of 21 species consisting mostly of night-blooming, moth-pollinated annuals and perennials. The current infrageneric classification based on differences in habit, floral symmetry, and fruit morphology recognizes eight sections within the genus. We examine the phylogenetic relationships of all 21 species of Gaura using DNA sequence data from the internal transcribed spacer region (ITS), the external transcribed spacer region (ETS), and the plastid trnL-F region. Combined analysis of these regions indicate Gaura is monophyletic only if it includes Stenosiphon, a monotypic genus comprised of S. linifolius. Within Gaura, our studies indicate that sections Gauridium, Schizocarya, Campogaura, Stipogaura, Xenogaura, and Gaura are monophyletic, but sections Xerogaura and Pterogaura are not and should be reevaluated. In addition, molecular data provide support for the hypothesis that G. sinuata and G. drummondii arose via interspecific hybridization followed by genome doubling; their influence on phylogenetic reconstruction is discussed.     

Phylogeny of the festucoid grasses of subtribe Loliinae and allies (Poeae, Pooideae) inferred from ITS and trnL-F sequences

Analyses of ribosomal ITS and chloroplast trnL-F sequences provide phylogenetic reconstruction for the festucoids (Poeae: Loliinae), a group of temperate grasses with morphological and molecular affinities to the large genus Festuca. Parsimony and Bayesian analyses of the combined ITS/trnL-F dataset show Loliinae to be monophyletic but unresolved for a weakly supported clade of 'broad-leaved Festuca,' a well-supported clade of 'fine-leaved Festuca,' and Castellia. The first group includes subgenera Schenodorus, Drymanthele, Leucopoa, and Subulatae, and sections Subbulbosae, Scariosa, and Pseudoscariosa of Festuca, plus Lolium and Micropyropsis. The second group includes sections Festuca, Aulaxyper, Eskia, and Amphigenes of Festuca, plus Vulpia, Ctenopsis, Psilurus, Wangenheimia, Cutandia, Narduroides, and Micropyrum. Subtribes Dactylidinae and Cynosurinae/Parapholiinae are sister clades and are the closest relatives of Loliinae. Vulpia is polyphyletic within the 'fine-leaved' fescues as revealed by the two genome analyses. Lolium is resolved as monophyletic in the ITS and combined analyses, but unresolved in the trnL-F based tree. Conflict between the ITS and the trnL-F trees in the placement of several taxa suggests the possibility of past reticulation events, although lineage sorting and possible ITS paralogy cannot be ruled out.     

Phylogeny and classification of Oleaceae based on rps16 and trnL-F sequence data

Phylogenetic relationships among 76 species of Oleaceae, representing all 25 recognized genera of the family, were assessed by a cladistic analysis of DNA sequences from two noncoding chloroplast loci, the rps16 intron and the trnL-F region. Consensus trees from separate and combined analyses are congruent and agree well with nonmolecular data (chromosome numbers, fruit and wood anatomy, leaf glycosides, and iridoids). The two debated genera Dimetra and Nyctanthes, previously suggested to belong to Verbenaceae (sensu lato) or Nyctanthaceae, are shown to belong to Oleaceae, sister to the hitherto genus incertae sedis Myxopyrum. This clade is also supported by anatomical and chemical data. The subfamily Jasminoideae is paraphyletic, and a new classification is presented. The subfamily level is abandoned, and the former Jasminoideae is split into four tribes: Myxopyreae (Myxopyrum, Nyctanthes, and Dimetra), Fontanesieae (Fontanesia), Forsythieae (Abeliophyllum and Forsythia), and Jasmineae (Jasminum and Menodora). The tribe Oleeae (previous subfamily Oleoideae) is clearly monophyletic, comprising the subtribes Ligustrinae (Syringa and Ligustrum), Schreberinae status novus (Schrebera and Comoranthus), Fraxininae status novus (Fraxinus), and Oleinae (12 drupaceous genera). An rps16 sequence obtained from Hesperelaea, known only from the type specimen collected in 1875, confirmed the placement of this extinct taxon in the subtribe Oleinae.     

Phylogeny and ecological radiation of New World thistles (Cirsium,Cardueae - Compositae) based on ITS and ETS rDNA sequence data

Sequence data from a portion of the external transcribed spacer (ETS) and internal transcribed spacers (ITS-1 and ITS-2) of 18S-26S nuclear ribosomal DNA were used to resolve historical biogeography and ecology of true thistles (Cirsium, Cardueae, Compositae) in the New World. The 650 base-pair, 3' portion of the ETS examined here showed a level of variation across taxa similar to that of the ITS sequences included. A maximum-likelihood tree based on combined ETS and ITS sequences leads us to suggest that the New World species of true thistles constitute a major lineage, which in turn comprises several smaller lineages. A western North American lineage shows weak quartet-puzzling support, but includes a well-supported lineage of species endemic to the California Floristic Province. Comparisons of this Californian lineage with other neoendemic angiosperm groups of the region show that the Californian Cirsium lineage exhibits unusually high ecological diversity for a group displaying such low levels of rDNA sequence divergence across taxa. Similarly low levels of sequence divergence were found throughout the New World Cirsium lineage. These results indicate either that Cirsium underwent a rapid ecological radiation in North America, or that rDNA evolution in North American Cirsium has been highly conservative.     

The secondary metabolite chemistry of the subtribe Gochnatiinae (tribe Mutisieae, family Compositae)

The chemistry of the subtribe Gochnatiinae is reviewed and some taxonomic implications are discussed.     

Phylogeny of the Dipsacales s.l. based on chloroplast trnL-F and ndhF sequences

Sequences of the chloroplast trnL-F region and 3(') end ndhF gene were used to elucidate phylogenetic relationships and the delimitation of families within Dipsacales s.l. Parsimony analyses of individual and combined data were conducted using maximum parsimony method. The most parsimonious tree based on combined trnL-F and 3(') end ndhF data set recognizes seven major clades of Dipsacales s.l. with the following relationships: Apiales (Adoxaceae ((Diervillaceae, Caprifoliaceae s.str.) (Linnaeaceae (Morinaceae (Dipsacaceae, Valerianaceae))))). Both Sambucus and Viburnum have close relationships with Adoxaceae, supporting their inclusion in this family. Caprifoliaceae s.l. (excluding Sambucus and Viburnum) is polyphyletic, and comprises three clades or families, i.e., Linnaeaceae (Abelia, Dipelta, Kolkwitzia, and Linnaea), Diervillaceae (Weigela and Diervilla) and Caprifoliaceae s.str. (Heptacodium, Leycesteria, Lonicera, Symphoricarpos, and Triosteum). This study focuses on the systematic position of Heptacodium, Triplostegia, and Morinaceae; and suggests that Heptacodium is closely related to the other Caprifoliaceae s.str.; Triplostegia is a sister to Dipsacaceae; Morinaceae, which has an affinity with Dipsacaceae, is possibly a sister group with Dipsacaceae-Valerianaceae clade. Our results are highly congruent with those of and.     

Morphological data indicates two major clades of the subtribe Gorteriinae (Asteraceae-Arctotideae)

The phylogeny of subtribe Gorteriinae (Asteraceae‐Arctotideae) is investigated by means of cladistic analysis of morphological characters. Two sister groups are formed, namely a Gorteria clade also containing Hirpicium and Gazania, and a Berkheya clade, which also contains Cullumia, Cuspidia, Didelta and Heterorhachis. The Gorteria clade has strong jackknife support and is diagnosed by four morphological characters (leaves with longitudinally striate hairs, fringed anther apical appendages, pollen of the “Gazania‐type”, and subulate‐ensiform, ascending style sweeping hairs) that are unique within the Asteraceae. The Berkheya clade is moderately supported and diagnosed by two characters without contradiction (spiny leaves, and mamillate, large style sweeping hairs). Hirpicium and Berkheya are paraphyletic, with the other, morphologically more homogeneous genera (Gorteria, and Gazania, Cullumia, Cuspidia, Didelta and Heterorhachis, respectively) nested within them. There is some evidence for a radiation of species of the summer rainfall area of South Africa and tropical Africa and the corresponding species are nested within a grade confined to the Cape Floristic Region. © The Willi Hennig Society 2006.     

A phylogeny of the "evil tribe" (Vernonieae: Compositae) reveals Old/New World long distance dispersal: support from separate and combined congruent datasets (trnL-F, ndhF, ITS)

The Vernonieae is one of the major tribes of the largest family of flowering plants, the sunflower family (Compositae or Asteraceae), with ca. 25,000 species. While the family's basal members (the Barnadesioideae) are found in South America, the tribe Vernonieae originated in the area of southern Africa/Madagascar. Its sister tribe, the Liabeae, is New World, however. This is the only such New/Old World sister tribe pairing anywhere in the family. The Vernonieae is now found on islands and continents worldwide and includes more than 1500 taxa. The Vernonieae has been called the "evil tribe" because overlapping character states make taxonomic delimitations difficult at all levels from the species to the subtribe for the majority of taxa. Juxtaposed with these difficult-to-separate entities are monotypic genera with highly distinctive morphologies and no obvious affinities to any other members of the tribe. The taxonomic frustration generated by these contrary circumstances has resulted in a lack of any phylogeny for the tribe until now. A combined approach using DNA sequence data from two chloroplast regions, the ndhF gene and the noncoding spacer trnL-F, and from the nuclear rDNA ITS region for 90 taxa from throughout the world was used to reconstruct the evolutionary history of the tribe. The data were analyzed separately and in combination using maximum parsimony (MP), minimum evolution neighbor-joining (NJ), and Bayesian analysis, the latter producing the best resolved and most strongly supported tree. In general, the phylogeny shows Old World taxa to be basal and New World taxa to be derived, but this is not always the case. Old and New World species are found together in two separate and only distantly related clades. This is best explained by long-distance dispersal with a minimum of two trans-oceanic exchanges. Meso/Central America has had an important role in ancient dispersals between the Old and New World and more recent movements from South to North America in the New World.     

Phylogeny of the core Malvales: evidence from ndhF sequence data

The monophyly of the group comprising the core malvalean families, Bombacaceae, Malvaceae, Sterculiaceae, and Tiliaceae, was recently confirmed by molecular studies, but the internal structure of this clade is poorly understood. In this study, we examined sequences of the chloroplast ndhF gene (aligned length 2226 bp) from 70 exemplars representing 35 of the 39 putative tribes of core Malvales. The monophyly of one traditional family, the Malvaceae, was supported in the trees resulting from these data, but the other three families, as traditionally circumscribed, are nonmonophyletic. In addition, the following relationships were well supported: (1) a clade, /Malvatheca, consisting of traditional Malvaceae and Bombacaceae (except some members of tribe Durioneae), plus Fremontodendron and Chiranthodendron, which are usually treated as Sterculiaceae; (2) a clade, /Malvadendrina, supported by a unique 21-bp (base pair) deletion and consisting of /Malvatheca, plus five additional subclades, including representatives of Sterculiaceae and Tiliaceae, and Durionieae; (3) a clade, /Byttneriina, with genera traditionally assigned to several tribes of Tiliaceae, plus exemplars of tribes Byttnerieae, Hermannieae, and Lasiopetaleae of Sterculiaceae. The most striking departures from traditional classifications are the following: Durio and relatives appear to be more closely related to Helicteres and Reevesia (Sterculiaceae) than to Bombacaceae; several genera traditionally considered as Bombacaceae (Camptostemon, Matisia, Phragmotheca, and Quararibea) or Sterculiaceae (Chiranthodendron and Fremontodendron) appear as sister lineages to the traditional Malvaceae; the traditional tribe Helictereae (Sterculiaceae) is polyphyletic; and Sterculiaceae and Tiliaceae, as traditionally circumscribed, represent polyphyletic groups that cannot sensibly be maintained with their traditional limits for purposes of classification. We discuss morphological characters and conclude that there has been extensive homoplasy in characters previously used to delineate major taxonomic groups in core Malvales. The topologies here also suggest that /Malvatheca do not have as a synapormophy monothecate anthers, as has been previously supposed but, instead, may be united by dithecate, transversely septate (polysporangiate) anthers, as found in basal members of both /Bombacoideae and /Malvoideae. Thus, “monothecate” anthers may have been derived at least twice, independently, within the /Bombacoideae (core Bombacaceae) and /Malvoideae (traditional Malvaceae).     

Radiation of southern African daisies: biogeographic inferences for subtribe Arctotidinae (Asteraceae, Arctotideae)

The majority of the approximately 80-90 species in subtribe Arctotidinae occur in southern Africa with the centre of diversity in the winter-rainfall region. Three species are restricted to afromontane eastern Africa and three species are endemic to Australia. To investigate biogeographic and phylogenetic relationships within Arctotidinae, sequence data from four cpDNA regions (psbA-trnH, trnT-trnL and trnL-trnF spacers and trnL intron) and the ITS nrDNA region for 59 Arctotidinae species were analyzed with parsimony and Bayesian-inference approaches. Eight well-supported major lineages were resolved. The earliest-diverging extant lineages are afromontane or inhabit mesic habitats, whereas almost all sampled taxa from the winter-rainfall and semi-arid areas have diverged more recently. Molecular dating estimated that the major clades diverged during the Miocene and Pliocene, which is coincident with the trend of increasing rainfall seasonality, aridification and vegetation changes in southwestern Africa. Trans-oceanic dispersal to Australia was estimated to have occurred during the Pliocene.     

Phylogeny and biogeography of Juglans (Juglandaceae) based on matK and ITS sequence data

We investigated phylogenetic and biogeographic relationships within Juglans (walnuts), a Tertiary disjunct genus, using 15 species of Juglans and related (Juglandaceae) outgroups. The relationships were analyzed using nucleotide sequences of the chloroplast gene matK and its flanking spacers and of the internal transcribed spacers (ITS) and 5.8S gene of the nuclear ribosomal DNA. The DNA sequences provided 246 informative characters for parsimony analysis. ITS data supported as monophyletic groups the four generic sections, Cardiocaryon, Dioscaryon, Rhysocaryon, and Trachycaryon. Within Rhysocaryon, the temperate black walnuts and the tropical black walnuts were supported as monophyletic groups. When the two data sets were combined, J. cinerea was nested within Cardiocaryon. Combined analysis with published nuclear DNA restriction site data placed J. cinerea in a monophyletic group with Cardiocaryon. These analyses consistently supported Juglans as a monophyletic group and as the sister group to the genus Pterocarya. The results of this work are consistent with the known geological history of Juglans. The fossil record suggests that the butternuts had evolved by the early Oligocene in North America. The presence of butternuts in Eurasia could be the result of migration from North America to Eurasia during the warming trend of the mid Oligocene.     

Pollen and the Evolution of Arctotideae (Compositae)

Recent molecular studies have elucidated the phylogeny of Compositae tribe Arctotideae, and found it to contain two, well supported, monophyletic subtribes, Arctotidineae and Gorteriinae, as well as some polyphyletic and problematic genera. On the basis of this new information, it may now be possible to identify diagnostic characters and synapomorphies to support the groupings defined within Arctotideae. Pollen characters have been shown to be particularly variable in Compositae. This paper aims to investigate the utility of those characters in the context of recent molecular phylogenies, in order to determine synapomorphic and diagnostic characters in Arctotideae. The pollen of each genus is described, illustrated with scanning electron micrographs, and optimised on a phylogeny of the tribe. Many pollen characters were found to be very informative when considered in the context of the current best estimate of phylogenetic relationships. Pollen morphology provides synapomorphies for clades at a number of hierarchical levels within Arctotideae, including the two subtribes, Arctotidinae and Gorteriinae, the grouping of Eremothamnus and Hoplophyllum, and smaller clades. It also supports the exclusion of Platycarpha from the tribe. The plesiomorphic palynological state for the tribe is discussed. Particular attention is paid to the evolution of different patterns of lophae (surface ridges). A single origin for the lophate condition is proposed as the most parsimonious mode of evolution in Arctotideae.     

Phylogenetic relationships and generic delimitation in subtribe Arctotidinae (Asteraceae: Arctotideae) inferred by DNA sequence data from ITS and five chloroplast regions

Asteraceae are the largest family in southern Africa. Elucidating its origins and radiation in the region requires well-supported species-level phylogenies of the lineages. This paper presents a phylogenetic framework for subtribe Arctotidinae, which have a southern and eastern African-Australian distribution centered in the winter-rainfall region of South Africa. DNA sequence data from five chloroplast fragments (ndhF, psbA-trnH, rps16, trnS-trnfM, and trnT-trnF) and the nuclear ITS region were analyzed separately and in combination using parsimony and Bayesian methods. The data sets comprised exemplars from 18 ingroup species, representing the five currently accepted genera, and four outgroup species from Gorteriinae. All analyses indicated Arctotis and Haplocarpha are polyphyletic as presently circumscribed. The Australian-endemic Cymbonotus lawsonianus was placed within a strongly supported clade also containing A. arctotoides from South Africa and H. schimperi from eastern Africa. Retention of Dymondia and resurrection of Landtia at generic level are strongly supported. The phylogenetic hypotheses indicate the subtribe might have originated in temperate southern or eastern Africa, or it was ancestrally widespread in southern Africa and has diversified vicariously. The derived placement of C. lawsonianus indicates long-distance dispersal from southern Africa to Australia occurred.