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1.
J Plant Res ; 136(4): 437-452, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37148377

RESUMO

A group of temperate grassland plant species termed the "Mansen elements" occurs in Japan and is widely distributed in the grasslands of continental East Asia. It has been hypothesized that these species are continental grassland relicts in Japan that stretch back to a colder age, but their migration history has not been elucidated. To assess the migration history of the Mansen elements, we performed phylogeographic analyses of Tephroseris kirilowii, a member of this group, using single-nucleotide polymorphisms (SNPs) obtained from multiplexed inter-simple sequence repeat genotyping by sequencing (MIG-seq). It was estimated that the Japanese populations of T. kirilowii were divided from those of continental East Asia at 25.2 thousand years ago (ka) with 95% highest probability density interval (HPD) of 15.3-40.0 ka and that Japanese clades first diverged at 20.2 ka with 95% HPD of 10.4-30.1 ka. As the climatically suitable range during the last glacial maximum (LGM) estimated using ecological niche modeling (ENM) was limited in Japan and there was a slight genetic differentiation among Japanese populations, a post-glacial expansion of T. kirilowii in the Japanese Archipelago was indicated.


Assuntos
Asteraceae , Pradaria , Filogeografia , Asteraceae/genética , Genótipo , Variação Genética , Repetições de Microssatélites/genética , Filogenia
2.
Ann Bot ; 131(5): 867-883, 2023 05 15.
Artigo em Inglês | MEDLINE | ID: mdl-36976653

RESUMO

BACKGROUND AND AIMS: Artemisia is a mega-diverse genus consisting of ~400 species. Despite its medicinal importance and ecological significance, a well-resolved phylogeny for global Artemisia, a natural generic delimitation and infrageneric taxonomy remain missing, owing to the obstructions from limited taxon sampling and insufficient information on DNA markers. Its morphological characters, such as capitulum, life form and leaf, show marked variations and are widely used in its infrageneric taxonomy. However, their evolution within Artemisia is poorly understood. Here, we aimed to reconstruct a well-resolved phylogeny for global Artemisia via a phylogenomic approach, to infer the evolutionary patterns of its key morphological characters and to update its circumscription and infrageneric taxonomy. METHODS: We sampled 228 species (258 samples) of Artemisia and its allies from both fresh and herbarium collections, covering all the subgenera and its main geographical areas, and conducted a phylogenomic analysis based on nuclear single nucleotide polymorphisms (SNPs) obtained from genome skimming data. Based on the phylogenetic framework, we inferred the possible evolutionary patterns of six key morphological characters widely used in its previous taxonomy. KEY RESULTS: The genus Kaschgaria was revealed to be nested in Artemisia with strong support. A well-resolved phylogeny of Artemisia consisting of eight highly supported clades was recovered, two of which were identified for the first time. Most of the previously recognized subgenera were not supported as monophyletic. Evolutionary inferences based on the six morphological characters showed that different states of these characters originated independently more than once. CONCLUSIONS: The circumscription of Artemisia is enlarged to include the genus Kaschgaria. The morphological characters traditionally used for the infrageneric taxonomy of Artemisia do not match the new phylogenetic tree. They experienced a more complex evolutionary history than previously thought. We propose a revised infrageneric taxonomy of the newly circumscribed Artemisia, with eight recognized subgenera to accommodate the new results.


Assuntos
Artemisia , Filogenia , Artemisia/genética , Folhas de Planta , Núcleo Celular
3.
J Plant Res ; 134(6): 1181-1198, 2021 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-34595677

RESUMO

To elucidate the origin and migration history of the "Mansen elements," a group of temperate grassland plants mainly distributed in northeastern Asia, phylogeographic analyses based on chloroplast DNA markers and double-digest restriction site-associated DNA sequencing (ddRAD-seq) data were performed on Viola orientalis, one of the representative species of the group. Phylogenetic analyses using ddRAD-seq data revealed that the populations of V. orientalis were clustered into five clades, among which the continental clades made of populations from Russia and Korea diverged more than 100,000 years earlier than the Japanese clades. The Japanese clade likely diverged during the last glacial period, followed by a further post-glacial divergence into the Kyushu and the Honshu subclades. Our study demonstrated that V. orientalis originated in the continental area of northeastern Asia and, during the last glacial period, has spread southward through the Korean Peninsula across the Japanese Islands. This finding supports the previously proposed evolutionary hypothesis regarding the origin and migration routes of the Mansen elements.


Assuntos
Viola , Violaceae , Variação Genética , Pradaria , Filogenia , Filogeografia , Plastídeos , Análise de Sequência de DNA
4.
Ann Bot ; 125(3): 521-532, 2020 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-31768517

RESUMO

BACKGROUND AND AIMS: Domatia are plant structures within which organisms reside. Callicarpa saccata (Lamiaceae) is the sole myrmecophyte, or 'ant plant', that develops foliar (leaf-borne) myrmeco-domatia in this genus. In this work we examined domatium development in C. saccata to understand the developmental processes behind pouch-like domatia. METHODS: Scanning electron microscopy, sectioning and microcomputed tomography were carried out to compare the leaves of C. saccata with those of the closely related but domatia-less myrmecophyte Callicarpa subaequalis, both under cultivation without ants. KEY RESULTS: Callicarpa saccata domatia are formed as a result of excess cell proliferation at the blade/petiole junctions of leaf primordia. Blade/petiole junctions are important meristematic sites in simple leaf organogenesis. We also found that the mesophyll tissue of domatia does not clearly differentiate into palisade and spongy layers. CONCLUSIONS: Rather than curling of the leaf margins, a perturbation of the normal functioning of the blade/petiole junction results in the formation of domatium tissue. Excess cell proliferation warps the shape of the blade and disturbs the development of the proximal-distal axis. This process leads to the generation of distinct structures that facilitate interaction between C. saccata and ants.


Assuntos
Formigas , Callicarpa , Animais , Folhas de Planta , Simbiose , Microtomografia por Raio-X
5.
Ecol Evol ; 9(12): 7262-7272, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31380048

RESUMO

The genetic diversity and structure of Pulsatilla cernua, a continental-grassland relict, were investigated using variations in chloroplast DNA (cpDNA) and microsatellites of nuclear DNA. In the analyses of three cpDNA regions, 17 haplotypes were found in 24 populations of P. cernua from Japan, Korea, and Russia. Although the route and time of migration between the continent of Asia and Japan could not be well resolved, the cpDNA haplotype network suggests the existence of several ancient lineages in Japan and a recent secondary migration from Japan to the continent. Microsatellite analyses did not indicate genetic structure among the Japanese populations, indicating the existence of gene flow across the distribution area until recently. These results indicate that the present fragmentation of P. cernua in Japan may reflect a rapid, recent reduction from a previously large, continuous distribution.

6.
Tokai J Exp Clin Med ; 43(4): 139-142, 2018 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-30488400

RESUMO

OBJECTIVE: Because of the shape of a double-lumen tube (DLT), it is more difficult to use for intubation than an ordinary endotracheal tube. We prospectively investigated the usefulness of the Airtraq DL® attached to the Universal Adapter for Smartphones® for DLT intubation. METHOD: At Tokai University Hachioji Hospital, anesthesiologists with ≥ 5 years' clinical experience intubated a tracheal intubation training mannequin with DLTs using the Airtraq DL® (Airtraq-alone phase) and the Airtraq DL® attached to the Universal Adapter for Smartphones® (adapter phase), and the time required was measured. RESULT: The mean time required for intubation was shorter in the adapter phase than in the Airtraq-alone phase for all anesthesiologists (adapter phase, 9.05±2.48 seconds; Airtraq-alone phase, 10.67±2.19 seconds). CONCLUSION: The use of Airtraq DL® a ttached to t he Universal Adapter for Smartphones® significantly reduced the time required for DLT intubation. Furthermore, the combination of these devices was found to be useful and safe for DLT intubation because they provide a significant amount of information on the area from the oral cavity to the opening of the trachea and have high educational value because their combined use allows several physicians to share imaging information.


Assuntos
Anestesiologia/instrumentação , Intubação Intratraqueal/instrumentação , Laringoscópios , Manequins , Smartphone , Desenho de Equipamento , Humanos , Estudos Prospectivos , Fatores de Tempo , Gravação em Vídeo
8.
J Plant Res ; 130(6): 953-972, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28536984

RESUMO

The genus Stevia comprises approximately 200 species, which are distributed in North and South America, and are representative of the species diversity of the Asteraceae in the New World. We reconstructed the phylogenetic relationships using sequences of ITS and cpDNA and estimated the divergence times of the major clade of this genus. Our results suggested that Stevia originated in Mexico 7.0-7.3 million years ago (Mya). Two large clades, one with shrub species and another with herb species, were separated at about 6.6 Mya. The phylogenetic reconstruction suggested that an ancestor of Stevia was a small shrub in temperate pine-oak forests and the evolutionary change from a shrub state to a herb state occurred only once. A Brazilian clade was nested in a Mexican herb clade, and its origin was estimated to be 5.2 Mya, suggesting that the migration from North America to South America occurred after the formation of the Isthmus of Panama. The species diversity in Mexico appears to reflect the habitat diversity within the temperate pine-oak forest zone. The presence of many conspecific diploid-polyploid clades in the phylogenetic tree reflects the high frequency of polyploidization among the perennial Stevia species.


Assuntos
Asteraceae/genética , Biodiversidade , Filogenia , Stevia/genética , Asteraceae/classificação , Evolução Biológica , Brasil , DNA de Cloroplastos/química , DNA de Cloroplastos/genética , DNA Intergênico/química , DNA Intergênico/genética , DNA de Plantas/química , DNA de Plantas/genética , Ecossistema , México , Filogeografia , Poliploidia , Alinhamento de Sequência , Análise de Sequência de DNA , Stevia/classificação
9.
PhytoKeys ; (62): 33-9, 2016.
Artigo em Inglês | MEDLINE | ID: mdl-27212880

RESUMO

A new species, Callicarpa bachmaensis Soejima & Tagane, sp. nov., is described and illustrated from Bach Ma National Park in Thua Thien Hue Province, Central Vietnam. This species has a characteristic liana habit, white corolla, and narrowly elliptic to narrowly lanceolate, entire, occasionally subequal leaves, by which it is clearly distinguished from the other previously known species of this genus.

10.
J Plant Res ; 129(4): 591-601, 2016 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-27059754

RESUMO

A tropical small tree, Callicarpa saccata, is known to have a symbiotic relationship with ants. It has sac-like structures at the base of the leaves that are inhabited by ants. No other species has been determined to be a myrmecophyte among the ca. 140 species of this genus. However, our recent field investigation discovered that two other species on Borneo (C. barbata and C. teneriflora) have hollow stems, which seem to be inhabited by ants. We observed the morphological features of these species in relation to their usage by ants, and became convinced that they are mymecophytic species. The molecular phylogenetic analyses using ITS and chloroplast regions suggest that C. saccata and C. teneriflora are closely related, but the differences in the myrmecophytic features of these species should be noted.


Assuntos
Formigas/fisiologia , Lamiaceae/anatomia & histologia , Lamiaceae/fisiologia , Filogenia , Animais , Sequência de Bases , Teorema de Bayes , Bornéu , Folhas de Planta/anatomia & histologia , Caules de Planta/anatomia & histologia
11.
Am J Bot ; 98(10): 1680-93, 2011 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-21965133

RESUMO

PREMISE OF THE STUDY: Biogeographic analyses of ferns with an eastern Asian-North American disjunction are few. The Adiantum pedatum complex has such a disjunct distribution. The monophyly of the complex needs to be tested and diversification history of the four species needs to be reconstructed. METHODS: Plastid (atpA, atpB, rbcL, trnL-F, and rps4-trnS) sequences of 100 accessions representing the biogeographic diversity of Adiantum were analyzed with parsimony and Bayesian inference. Biogeography of the Adiantum pedatum complex was inferred using programs DIVA and LAGRANGE. Divergence times of clades were estimated with the program BEAST. KEY RESULTS: The A. pedatum complex is monophyletic and sister to the eastern Asian A. edentulum. Accessions of A. pedatum do not form a clade; instead three subgroups are recognizable. The clade of A. aleuticum and A. viridimontanum is nested within A. pedatum. The Asian A. myriosorum is sister to the A. pedatum-A. aleuticum clade. Both DIVA and LAGRANGE analyses suggest an eastern Asian origin of the A. pedatum complex. The age of the crown A. pedatum complex is dated to be at 4.27 (2.24-6.57) million years ago. CONCLUSIONS: The currently recognized eastern Asian-North American disjunct species A. pedatum needs to be segregated into three species, corresponding to populations in eastern North America, China, and Japan. The eastern Asian-North American disjunction in the complex is inferred to be the result of two intercontinental migrations, one from eastern Asia into North America in the late Tertiary and the other from North America back to eastern Asia in the Pleistocene.


Assuntos
Adiantum/genética , Filogeografia , Ásia , Variação Genética , América do Norte , Filogenia , Fatores de Tempo
12.
J Plant Res ; 120(5): 585-93, 2007 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-17710369

RESUMO

The karyotype of diploid Aster iinumae is morphologically similar to that of diploid Aster ageratoides var. ageratoides, however, its chromosome size is apparently smaller (S-type chromosomes versus L-type chromosomes, respectively). The hybrid origin of tetraploid Aster microcephalus var. ovatus (LS-type chromosomes) has previously been suggested by cytogenetics and chloroplast DNA (cp DNA) data. The cp DNA phylogeny also implies that the S-type chromosome is apomorphic, which means that genome size reduction occurred on the evolutionary way to A. iinumae. In this study, we have demonstrated that the chromosome size difference does not depend on the intensity of chromosome condensation but on the DNA content. The simultaneous genomic in situ hybridization (GISH) results show the similarity between S-type chromosomes of A. iinumae and A. microcephalus var. ovatus, and between L-type chromosomes of A. ageratoides and A. microcephalus var. ovatus, which provide additional evidence for A. microcephalus var. ovatus being a tetraploid amphidiploid produced by hybridization between S-type chromosomes and L-type chromosomes. The distribution patterns of Ty1-copia-like retrotransposons were similar in L- and S-type chromosomes. The copies of this retrotransposon dispersed uniformly on all chromosomes, and it is not yet apparent how the Ty1-copia-like retrotransposon affects the size difference between them.


Assuntos
Aster/genética , Cromossomos de Plantas , Genoma de Planta , Poliploidia , Retroelementos , DNA de Plantas/análise , Citometria de Fluxo , Hibridização in Situ Fluorescente , Cariotipagem , Filogenia
13.
Am J Bot ; 93(2): 278-87, 2006 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-21646189

RESUMO

Seventy-nine species representing 12 genera of Vitaceae were sequenced for the trnL-F spacer, 37 of which were subsequently sequenced for the atpB-rbcL spacer and the rps16 intron. Phylogenetic analysis of the combined data provided a fairly robust phylogeny for Vitaceae. Cayratia, Tetrastigma, and Cyphostemma form a clade. Cyphostemma and Tetrastigma are each monophyletic, and Cayratia may be paraphyletic. Ampelopsis is paraphyletic with the African Rhoicissus and the South American Cissus striata nested within it. The pinnately leaved Ampelopsis form a subclade, and the simple and palmately leaved Ameplopsis constitutes another with both subclades containing Asian and American species. Species of Cissus from Asia and Central America are monophyletic, but the South American C. striata does not group with other Cissus species. The Asian endemic Nothocissus and Pterisanthes form a clade with Asian Ampelocissus, and A. javalensis from Central America is sister to this clade. Vitis is monophyletic and forms a larger clade with Ampelocissus, Pterisanthes, and Nothocissus. The eastern Asian and North American disjunct Parthenocissus forms a clade with Yua austro-orientalis, a species of a small newly recognized genus from China to eastern Himalaya. Vitaceae show complex multiple intercontinental relationships within the northern hemisphere and between northern and southern hemispheres.

14.
J Plant Res ; 117(3): 199-207, 2004 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-15103563

RESUMO

Thirty species and one variety of Symplocos (Symplocaceae), including all taxa distributed in Japan, were phylogenetically analyzed with DNA sequence data. The evolution of morphological characters is discussed on the basis of the phylogenetic relationships obtained. All species were Asian, except one, S. austromexicana, from Mexico. The nuclear ribosomal internal transcribed spacer (ITS) region and two intergenic spacer regions, between trnL and trnF, and between trnH and psbA of chloroplast DNA were used. The topologies of trees obtained from ITS and the chloroplast intergenic spacers are largely congruent. S. sonoharae, the representative of the subgenus Symplocos in Asia, was sister to all other species. The position of the American species, S. austromexicana, which also belongs to the subgenus Symplocos, was not well resolved. The phylogenetic tree based on combined sequence data largely supports the monophyletic origin of the infrageneric sections proposed earlier. However, the phylogenetic relationship between them is not well resolved, probably due to rapid diversification. The section Palura, a deciduous group, is well defined in the DNA analysis, suggesting its independent status in the genus Symplocos. In spite of their morphological divergence, the three endemic species of the Bonin Islands are monophyletic. The occurrence of curved seeds seems to be homoplastic, scattered over the phylogenetic tree without showing a particular infrageneric relationship.


Assuntos
Núcleo Celular/genética , DNA de Cloroplastos/genética , Magnoliopsida/genética , Filogenia , Ásia , DNA Intergênico/genética , DNA de Plantas/química , DNA de Plantas/genética , DNA Espaçador Ribossômico/genética , Magnoliopsida/classificação , México , Dados de Sequência Molecular
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