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1.
Phylogenetic analysis of chloroplast DNA restriction site data for 76 of the 302 genera of Heliantheae sensu lato using 16 restriction endonucleases reveals that subtribe Ecliptinae is polyphyletic and that its genera are distributed in four different lineages. The ecliptinous genera Squamopappus, Podachaenium, Verbesina, and Tetrachyron (of the Neurolaeninae), along with other members of subtribe Neurolaeninae are the basalmost clades of the paleaceous Heliantheae. The mostly temperate species of subtribe Ecliptinae (exemplified by Balsamorhiza, Borrichia, Chrysogonum, Engelmannia, Silphium, Vigethia, and Wyethia) are strongly nested in a clade with the Mesoamerican monotypic genus Rojasianthe as basal. The genera characterized by marcescent ray corollas traditionally classified in subtribe Zinniinae constitute a strongly supported group sister to Acmella, Spilanthes, and Salmea. The largest clade of ecliptinous genera is the most recently derived group within Heliantheae sampled. This large group of mostly Neotropical lowland genera (variously characterized by their winged cypselae, foliaceous phyllaries, and opposite phyllotaxy and exemplified by Perymenium, Wedelia, and Zexmenia) has been and continues to be the most challenging group from a taxonomic standpoint. The study provides new insights as to their relationships that will have a positive impact in future monographic studies of the group. The genera of the Espeletiinae form a monophyletic clade and are sister to members of the Milleriinae and Melampodiinae. This result is consistent with their traditional taxonomic placement with genera such as Smallanthus with which they share a tendency for functionally staminate disc flowers. The phylogenetically enigmatic genus Montanoa is sister to Melampodium. Members of subtribe Galinsoginae are clustered in two main lineages that correspond to the traditional division of the subtribe based on pappus characteristics. There is no support for the monophyly of subtribe Galinsoginae, and the same results indicate some of its genera are paraphyletic.  相似文献   

2.
The phylogenetic relationships of Silphium and subtribe Engelmanniinae were examined using DNA sequence data. The internal transcribed spacer (ITS) region and the external transcribed spacer (ETS) region were sequenced for 39 specimens representing the six genera of subtribe Engelmanniinae (Berlandiera, Chrysogonum, Dugesia, Engelmannia, Lindheimera, and Silphium), plus five additional genera identified as closely related to the Engelmanniinae by chloroplast DNA restriction site analysis, and three outgroups. Phylogenetic analysis supported the monophyly of Silphium with Lindheimera as sister. Silphium can be divided into two sections based upon two well-supported clades that correspond to root type and growth form. These results also supported the expansion of subtribe Engelmanniinae to include Balsamorhiza, Borrichia, Rojasianthe, Vigethia, and Wyethia. We hypothesize that subtribe Engelmanniinae originated in Mesoamerica and later radiated to the United States. We suggest that the cypsela complex, which is present in Berlandiera, Chrysogonum, Engelmannia, and Lindheimera, arose only once and was subsequently lost in Silphium.  相似文献   

3.
The tribe Arctotideae (African Daisies), of the flowering plant family Compositae (Asteraceae), is a diverse and interesting group with a primarily southern African distribution (ca. 13 genera, 215 species) and many species in the Cape Floristic Region. It is divided into two subtribes: Arctotidinae (ca. 5 genera, 85 species) and Gorteriinae (ca. 8 genera, 130 species). The monophyly of the genera within the subtribe Gorteriinae and their relationship to one another was investigated using 71 samples/212 sequences including 64/141 of which are newly reported from three phylogenetic markers, two from chloroplast DNA (trnL-F and ndhF) and one from the nuclear genome (ITS). The outgroup was composed of seven members from the sister subtribe. Results show the subtribe Gorteriinae to be divided into three monophyletic groups, the Gazania-Hirpicium-Gorteria group, the Didelta group, and the Berkheya-Cullumia group. Within these three groups are 13 sub-groups, one of which has sub-clades. The genus Berkheya Ehrh. is paraphyletic, falling into five different sub-groups. The two monotypic genera, Cuspidia and Heterorhachis are not nested within any of the Berkheya clades. Hirpicium and Cullumia each have most of their taxa in a monophyletic group, but they also have one or two taxa associated with other clades. Four of the five sub-groups of Berkheya have morphologically recognizable shared characters, such as habit and spines that have been recognized by past studies. However, the grouping of one species with Didelta is difficult to explain. Support for the major clades and most of the sub-groups is strong but the relationships among some of the terminal taxa are variable.  相似文献   

4.
The Compositae (Asteraceae) is the largest flowering plant family if described, accepted taxa are considered. Recent revisions in the taxonomy of the family have resulted in the recognition of ten subfamilies and 35 tribes. The tribe Arctotideae is one of the smallest, with around 200 species; it contains two subtribes and several hard-to-place taxa. Previous work has shown that the subtribe Arctotidinae is well defined and is restricted to southern Africa, except for the Australian genus Cymbonotus . Molecular data from internal transcribed spacer (ITS), ndh F, and trn L-F sequences were used (24 previously published sequences; 47 new sequences) to determine the patterns of relationships within the subtribe. Twenty-three samples from the ingroup, including members of all genera and all three species of Cymbonotus , were included in the analysis, together with two outgroup taxa. Cymbonotus is monophyletic and deeply embedded in the subtribe; Haplocarpha is paraphyletic and basal in position; all other genera are monophyletic; however, Arctotis has over 60 species and only eight were sampled for this study, so additional work may prove otherwise. Arctotis is nested high in the tree and has short branch lengths; this may reflect recent radiation. By contrast, the species of the paraphyletic and basal Haplocarpha have long branches, which may indicate an older radiation and a shared ancestry with the remainder of the subtribe. The presence of Cymbonotus in Australia is most probably the result of long-distance dispersal.  Journal compilation © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 153 , 1–8. No claim to original US government works  相似文献   

5.
测定了簇毛黄耆亚属(Pogonophace)4组8种和外类群Caragana roborovskyi的ITS序列,从GenBank中调出相关12属47种的ITS序列,组成数据距阵,应用PAUP程序中的最大简约法构建了系统发育树状图。扁荚组(Sect.Sesbanella)与亚属其余类群在系统树上处于不同的分支,亲缘关系较远这个亚属不是一个单系类群;膨果组(Sect.Bibracteola)。背扁组(Sect.Phyllolobium)和袋果组(Sect.Trichostylus)作为一个单系类群能得到ITS序列的支持,但与分组以及膨果组下系的划分都得不到ITS序列分析的支持。  相似文献   

6.
The subtribe Espeletiinae (Asteraceae, Heliantheae) comprises morphologically and ecologically diverse plants endemic to the tropical montane paramos of the Andes of Venezuela, Colombia, and Ecuador. Though the ecophysiology and ecology of this adaptive radiation have been well studied, relationships among taxa in the subtribe and between the subtribe and other taxa in the Heliantheae are poorly known. In this study, sequences from the internal transcribed spacer (ITS) region of nuclear ribosomal DNA are used to test previous hypotheses about the phylogenetic position of the Espeletiinae within the Heliantheae and to determine which taxa are the subtribe's closest relatives. Gene phylogenies based on maximum parsimony analyses reveal that the Espeletiinae clade is nested well within the subtribe Melampodiinae and thus should be considered a monophyletic complex of species, not a separate subtribe. The most parsimonious gene trees suggest that the genus Ichthyothere may be the sister taxon to the Espeletia complex and that the genus Smallanthus and a species of Rumfordia are likely among the complex's other closest living relatives. These data offer preliminary insights into the origins of this adaptive radiation and the broader phylogenetic context in which it occurred.  相似文献   

7.
A phylogenetic analysis is provided for 70% of the representatives of genus Gavilea, as well as for several species of the remaining genera of subtribe Chloraeinae: Bipinnula, Chloraea and Geoblasta. Sequences from the plastid markers rpoC1, matK-trnK and atpB-rbcL and the nuclear marker ITS, were analyzed using Maximum Parsimony and Bayesian Inference. Monophyly of subtribe Chloraeinae was confirmed, as well as its position inside tribe Cranichideae. Neither Chloraea nor Bipinnula were recovered as monophyletic. Gavilea turned out polyphyletic, with Chloraeachica embedded in the genus while Gavilea supralabellata was related to Chloraea and might be a hybrid between both genera. None of the two sections of Gavilea were monophyletic, and the topologies obtained do not suggest a new division of the genus.  相似文献   

8.
The molecular phylogeny of Senecio sect. Jacobaea (Asteraceae; Senecioneae) was studied to clarify species composition and interspecific relationships of Senecio sect. Jacobaea. This information is necessary for studies seeking explanations of the evolutionary success of Senecio, in terms of high species numbers and the evolution of chemical defense mechanisms. Parsimony analyses with 60 species of the tribe Senecioneae, representing 23 genera and 11 sections of Senecio, based on DNA sequence data of the plastid genome (the trnT-L intergenic spacer, the trnL intron, and two parts of the trnK intron, flanking both sides of the matK gene) and nuclear genome (ITS1, 5.8S, and ITS2 gene and spacers) show that sect. Jacobaea is a strongly supported monophyletic group. Fifteen species have been identified as members of section Jacobaea, including three species that have been consistently ascribed to this section in taxonomic literature and 12 species that were either placed in other sections of Senecio or not exclusively ascribed to sect. Jacobaea. This section was traditionally circumscribed as a group of European, biennial, or perennial herbs with pinnately incised leaves, but the results of this study show that one annual species, a species from northeastern Asia, and a species growing in the Himalayas are members of sect. Jacobaea as well. Furthermore, not all species in the section have pinnately incised leaves. The genera Emilia, Packera, and Pseudogynoxys form the sister clade of sect. Jacobaea, but this relationship lacks strong bootstrap support and thus remains provisional.  相似文献   

9.
The phylogenetic relationships of Osmanthus Lour.were investigated using the nuclear ribosomal internal transcribed spacer(ITS)regions and non-coding chloroplast regions(psbA-trnH,trnL-F).The two datasets support the conclusion that Osmanthus is polyphyletic.with some species of the subtribe Oleinae nested within Osmanthus.Osmanthus didymopetalus P S.Green is nested within the clade formed by species of section Osmanthus in two trees.Osmanthus attenuatus P.S.Green.O.Funnanensis P.S.Green,and O gracilinervis R.L.Lu of traditional section Osmanthus are clearly divergent from other accessions,and do not form a monophyletic group with other Osmanthus accessions.Osmanthus marginatus Hemsl.is embedded in the clade formed by species of section Osmanthus in the ITS tree.In cpDNA trees all species of section Osmanthus are placed in the large clade and all species of section Leiolea formed a group.The taxonomic incongruence among trees for ITS and cpDNA indicate hybridization.as introgression may have occurred among some species of sections Osmanthus and Leiolea.Phylogeny of Osmanthus is discussed in light of molecular and morphological data,and a revised infrageneric classification with three sections(Leiolea,Siphosmanthu,and Osmanthus)is presented.The section Linocieroides is abandoned and united with section Osmanthus.  相似文献   

10.
A phylogeny of Packera is presented based on sequence data from the internal transcribed spacer region of nuclear ribosomal DNA of 26 species (28 populations) of Packera and 23 outgroup taxa, including representatives of all three subtribes of the Senecioneae. The results support a Mexican origin for Packera, with its closest relatives found among Old World taxa in the subtribe Senecioninae, such as Senecio jacobaea and Pericallis. Packera species from the west coast of the United States, previously included in the section Bolanderi of Greenman, are part of a basal assemblage including species of Greenman's Mexican section Sanguisorboidei. The rest of Packera separates into two sister groups, one containing species from the Arizona-New Mexico region and the other containing more geographically diverse taxa. Among the outgroups, New World Senecio species are monophyletic and two Tussilaginoid assemblages are strongly supported; the Tephroseroid group (Tephroseris and Sinosenecio) plus Petasites combine with the Luina complex to form a clade of north temperate taxa, and the four Mexican genera (Psacalium, Robinsonecio, Barkleyanthus, and Pittocaulon) form a monophyletic group.  相似文献   

11.
Phylogenetic relationships were inferred for the African subtribe Disinae (Orchidoideae, Orchidaceae), which include the large genus Disa and the small genus Schizodium. One nuclear (ITS) gene region and two plastid (trnLF and matK) gene regions were sequenced for 136 ingroup, representing 70% of all known Disinae species, as well as for 7 outgroup taxa. The combined data matrix contained 4094 characters and was analysed using parsimony and Bayesian inference. Our results show that the generic status of Schizodium can no longer be supported, as it is deeply embedded within the genus Disa. Furthermore, the currently recognised subgenera do not reflect the phylogenetic relationships and should be rejected. Several of the currently recognised sections are monophyletic, others contain misplaced elements, while some are polyphyletic. Morphological divergence, rather than convergence, has hampered previous attempts at a phylogenetic classification of the Disinae. On the basis of our molecular phylogenetic hypothesis, we propose a monotypic subtribe Disinae and a subdivision of the genus Disa into 18 sections.  相似文献   

12.
Abstract: Sequences of the internal transcribed spacers (ITS1 and ITS2) of nuclear ribosomal DNA were analysed for 44 Artemisia species (46 populations) representing all the five classical subgenera and the geographical range of the genus, 11 species from 10 genera closely related to Artemisia, and six outgroup species from five other genera of the Anthemideae. The results definitely support the monophyly of the genus Artemisia in its broadest sense (including some taxa segregated as independent genera, like Oligosporus and Seriphidium ). Eight main clades are established in this molecular phylogeny within Artemisia; they agree in part with the classical subdivision of the genus, but they also suggest that some infrageneric groups must be redefined, especially the subgenus Artemisia. The subgenera Tridentatae and Seriphidium are independent from each other. Some of the satellite genera are clearly placed within Artemisia ( Artemisiastrum, Filifolium, Mausolea, Picrothamnus, Sphaeromeria, Turaniphytum ), whereas some others fall outside the large clade formed by this genus (Brachanthemum, Elachanthemum, Hippolytia, Kaschgaria). Our results, correlated to other data such as pollen morphology, allow us to conclude that the subtribe Artemisiinae as currently defined is a very heterogeneous group. Affinities of the largest genus of the subtribe and tribe, Artemisia, and of other genera of the subtribe to some genera from other subtribes of the Anthemideae strongly suggest that subtribe Artemisiinae needs a deep revision and redefinition. Phylogenetic utility of region trnL-F of the plastid DNA in the genus Artemisia and allies was also evaluated: sequences of the trnL-F region in Artemisia do not provide phylogenetic information.  相似文献   

13.
The internal transcribed spacer (ITS) regions of 18S–25S nuclear ribosomal DNA from representatives of 23 species of the subtribeGentianinae and one outgroup species (Centaurium capitatum) were analyzed by polymerase chain reaction amplification and direct DNA sequencing. Within the taxa analyzed, the length of the ITS1 region varied from 221 to 233 bp, ITS2 from 226 to 234 bp. Of the aligned sequences of 497 positions, 151 sites involved gaps or nucleotide ambiguity, 133 were invariable and 213 showed divergence. In pairwise comparisons among the taxa of the subtribeGentianinae and the outgroup, sequence divergence ranged from 1.3% to 34.1% in ITS1, from 0 to 28.1% in ITS2 and from 0.6% to 27.5% in combined ITS1 and ITS2. Phylogenetic trees generated from ITS sequences were highly resolutive and principally concordant with morphological classifications for the major phylogenetic divisions in the subtribe. An ancient divergence leading to two evolutionary lines was suggested in the subtribe by both DNA sequence and morphological data. One line encompasses the generaGentiana, Crawfurdia andTripterospermum, morphologically characterized by their glands on the base of ovary and their plicate corolla, while the other line involves all other members of the subcribe surveyed, characterized by their epipetalous glands and simple corolla without plicae.Megacodon, with glands on the base of ovary but without plicae on its corolla, was revealed to be more related to the latter group than to the former.Comastoma, Gentianella andGentianopsis were shown to be well-defined monophyletic genera.Pterygocalyx showed much closer affinity toGentianopsis than to any other genus. Some conflictions were detected in the genusSwertia.  相似文献   

14.
Chloroplast trnL-F sequence data, nuclear ribosomal internal transcribed spacer (ITS) sequence data, and morphology were used to analyze phylogenetic relationships among members of the subtribe Strobilanthinae. Parsimony and maximum likelihood analyses of trnL-F indicate that the Strobilanthinae are a monophyletic group. While parsimony analysis of ITS recovers a nonmonophyletic subtribe, maximum likelihood analysis of ITS corroborates results from trnL-F and suggests that systematic error is impacting on ITS parsimony analysis. A combined ITS and trnL-F analysis strengthens the signal and also recovers a monophyletic subtribe. All analyses indicate that Hemigraphis, Sericocalyx, and Strobilanthes are nonmonophyletic. With one exception, all morphological characters included in a combined ITS and morphological analysis are homoplastic. The prospect for a new informative generic classification of the Strobilanthinae aiming to recognize and diagnose only monophyletic groups is considered. While some groups can be diagnosed, adequate diagnosis of the majority of groups remains problematic. Consequently, a single expanded genus Strobilanthes sensu lato is proposed at the level of the well-supported and monophyletic Strobilanthinae.  相似文献   

15.
Ge S  Li A  Lu BR  Zhang SZ  Hong DY 《American journal of botany》2002,89(12):1967-1972
Phylogenetic relationships were inferred using nucleotide sequences of the chloroplast gene matK for 26 species representing 11 genera of the tribe Oryzeae and three outgroup species. The sequenced fragments varied from 1522 base pairs (bp) to 1534 bp in length with 15.4% variable and 7.9% phylogenetically informative sites when the outgroups were excluded. The aligned sequences were analyzed by maximum parsimony and neighbor-joining methods. Analyses of the sequence data indicated that species of Oryzeae form a strongly supported monophyletic group, concordant with previous morphological and anatomical evidence. The tribe Oryzeae can be divided into two monophyletic lineages, corresponding to the traditionally recognized subtribes Oryzinae and Zizaniinae. The first subtribe consists of Oryza and Leersia, while the subtribe Zizaniinae includes the remaining genera. The matK sequence data did not support the close affinities of the monoecious genera in Oryzeae, implying the possibility of multiple origins of the floral structures in the tribe. It is noteworthy that Porteresia coarctata is closely related to Oryza species, suggesting that it should be treated as a member in the genus Oryza rather than a separate monotypic genus.  相似文献   

16.
The Euptychiina is one of the more diverse lineages of satyrine butterflies, represented by over 300 species. The first phylogenetic analyses of the subtribe is presented based on 2506 aligned nucleotide sequences obtained from 69 individuals spanning 28 ingroup genera and nine outgroup genera. Two genes were used, the mitochondrial gene cytochrome oxidase 1 (1268 bp) and the nuclear gene elongation factor-1alpha (1238 bp). The subtribe is never recovered as monophyletic in analyses using parsimony, maximum likelihood, or Bayesian inference. Several euptychiine genera are placed basal to the ingroup, but support is found only for Euptychia and Oressinoma. Three main lineages within the ingroup were clearly defined and many taxonomic groupings within the clades strongly supported. The majority of genera tested were paraphyletic or polyphyletic. Based on results presented here and novel host use, a close relationship of Euptychia to the Indo-Australian tribe Ragadiini is hypothesized. Origins of the group remain unclear, but the basal position of most of the Nearctic genera is discussed.  相似文献   

17.
As part of our ongoing phylogenetic study of genusHypericum, nuclear ribosomal DNA internal transcribed spacer sequences were analyzed for 36 species ofHypericum as ingroup and two species ofThornea as outgroup. This sampling included most of the previously described species from both Korea and Japan. The ITS phylogeny suggested that the surveyedHypericum species belong to a monophyletic section,Trigynobrathys, and a polyphyletic section,Hypericum. In addition, two monotypic sections,Sampsonia andRoscyna, were identified. Members of sectionHypericum occur in four different lineages worldwide, which imply at least four independent origins. The Korean and Japanese species of sectionHypericum form a monophyletic group, except forH. vulcanicum. Instead, that particular species belongs to a distinct monophyletic group withH. scoreri andH. formosa from other geographic areas, and is a sister to sectionTrigynobrathys. The Korean and Japanese species of sectionTrigynobrathys show a monophyletic origin.H. sampsonii is now recognized as a distinct section rather than being a member of sectionsHypericum orDrosocarpium, as had been indicated previously. Our results differ somewhat from those of recent morphological and cytological studies. The phylogenetic relationships among Korean and Japanese species have now been mostly resolved via ITS phylogeny.  相似文献   

18.
The oil-secreting orchids of southern Africa belong to the sub-tribe Coryciinae within Diseae. A phylogeny of Diseae is inferred using sequence data from all genera in the tribe, with an emphasis on resolving generic classifications within Coryciinae. Nuclear (ITS) and plastid (trnLF and matK) gene region sequences were analysed for 79 ingroup taxa and three outgroup taxa. Coryciinae is confirmed to be diphyletic, with Disperis and Coryciinae sensu stricto (s.s.) forming separate monophyletic clades. The current genera Corycium and Pterygodium are not monophyletic according to our analysis and we propose a subdivision of Coryciinae s.s. into 10 monophyletic clades including three monotypic groups. Previous generic classifications of Coryciinae s.s. have been hampered by convergent evolution of floral parts, a consequence of few pollinator species and limited pollinia attachment sites in the oil-bee pollination system common to this group.  相似文献   

19.
Phylogenetic relationships among nine genera and 28 species of the southern African tribe Podalyrieae were estimated from sequences of the internal transcribed spacer (ITS) of nuclear ribosomal DNA as well as morphological and chemical data. Morphological and ITS sequence data produced cladograms with similar topologies, both supporting the monophyly of Podalyrieae (excluding Hypocalyptus ). The combined data sets indicate that subtribe Xiphothecinae are monophyletic, but embedded within Podalyriinae. The high degree of congruence between previous taxonomic hypotheses and those based on DNA data provides further evidence for the utility of ITS sequences in studying phylogeny.  © 2002 The Linnean Society of London , Botanical Journal of the Linnean Society , 2002, 139 , 159–170.  相似文献   

20.
Vernonieae is one of the major tribes in Asteraceae (subfamily Cichorioideae) with ca. 1,100 species placed into 129 genera. Currently, 21 subtribes are recognized in Vernonieae and one of them is Lychnophorinae, almost entirely endemic to Brazil, containing 11 genera and ca. 100 species. About 42 % of Lychnophorinae genera are monophyletic, reflecting the poorly understood relationships among the members of the group. Trichomes are one of the most useful anatomical characters to be used in angiosperm taxonomy; they are diverse, exist in many taxa and are not difficult to study. This work intends to illustrate non-glandular leaf trichome diversity in Lychnophorinae and discuss this diversity in the light of the subtribe’s taxonomy. Sampled material included 67 species of 11 genera. Macerations and free hand sections were performed to be analyzed in the light microscope and photographed. A phenogram was generated using a matrix with 67 terminals (species) and 18 characters coded as binary. The subtribe Lychnophorinae displays a great diversity of non-glandular trichomes (5 types and 18 subtypes). The present study reveals the great diversity of non-glandular trichomes in Lychnophorinae. While trichome complement is of little use to distinguish genera, it appears to be a valuable characteristic at a lower taxonomic level to identify closely morphologically related species.  相似文献   

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