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1.
Previous phylogeographic studies of alpine plants in Japan have inferred that populations in central Honshu persisted during the Pleistocene climatic oscillations and suggested interglacial survival in high mountains. However, Arcterica nana (Maxim.) Makino (Ericaceae) exhibits a homogenous genetic structure throughout Japan and may therefore have a unique phylogeographic history. This inconsistency could have resulted from insufficient resolution of previously analyzed chloroplast DNA sequences. Therefore, we conducted a phylogeographic investigation based on amplified fragment length polymorphisms. Using 176 individuals from 21 populations, the relationships among individuals and populations were determined by principal coordinate analysis and a neighbor-joining tree, respectively. In addition, genetic differentiation was estimated using analysis of molecular variance and spatial autocorrelation analysis. These analyses demonstrate a homogenous structure throughout the entire Japanese range, supporting the previous cpDNA phylogeography. Although this genetic structure is inconsistent with those of other alpine plants, it is difficult to postulate that pre-existing genetic differentiation was swamped exclusively within A. nana. Therefore, this homogenous genetic structure may have been caused by the distinct history of populations of A. nana. Specifically, the southern-ward migration and the subsequent continuous populations enabled gene flow throughout the Japanese archipelago during the last glacial period. Thus, our data suggest that alpine plants in the Japanese archipelago did not always experience a shared distribution change following climatic oscillations.  相似文献   

2.
Aim  This study aims to elucidate the phylogeography of the Japanese endemic alpine plant, Phyllodoce nipponica Makino (Ericaceae) and to infer the location of refugia of alpine plants in Japan during climatic oscillations.
Location  Alpine zone in the Japanese archipelago.
Methods  We determined the chloroplast (cp) DNA haplotypes of 155 individuals (22 populations) based on sequence data from the trnL-F and trnT-L intergenic spacers and the trnL intron, whose phylogenetic relationships were analysed using the program tcs . To examine the genetic structure, analysis of molecular variance ( amova ) was carried out and the population differentiation was shown by the parameters G ST and N ST.
Results  The haplotype composition and the results of amova showed that populations in the Japanese Central Mountain Region (JCMR) and in the westernmost region were highly divergent (18.8%). The diversity within populations was very high in the JCMR ( h S = 0.421); less variation was found within populations located in other regions at lower elevations.
Main conclusions  Phyllodoce nipponica survived climatic changes during the Quaternary in the JCMR and the westernmost region. Most of the distribution range was colonized during only one range expansion. The source location from which the range expansion occurred was unclear.  相似文献   

3.
Phytochromes play a key role in allowing plants to monitor their surrounding environment and, conversely, adaptation to local environments has driven the evolutionary history of phytochromes. As a result of natural selection, polymorphisms in phytochrome genes would thus be expected to exhibit locus‐specific phylogeographic structure. To evaluate this hypothesis, we conducted a phylogeographic investigation based on four nuclear genes, including two phytochrome genes (PHYB and PHYE) using 155 samples of Arcterica nana from the entire range of the Japanese archipelago. Bayesian clustering revealed geographic differentiation between northern and southern Japan when all four genes were included. However, this geographic differentiation is inconsistent with previously reported genetic structure of genome‐wide polymorphisms based on amplified fragment length polymorphisms, as these did not show geographic differentiation throughout the Japanese archipelago. In contrast, the north–south differentiation was not apparent when PHYE was excluded. This indicates that PHYE alone could be responsible for the north–south differentiation (FCT = 0.15, P < 0.001). Furthermore, a single nonsynonymous polymorphism (C360T) strongly contributed to geographic differentiation (FCT = 0.57, P < 0.001) and its corresponding amino acid replacement (P120L) was significantly under positive selection based on maximum likelihood analysis (P = 0.98). Consequently, the locus‐specific geographic differentiation in PHYE could be caused by natural selection, suggesting the involvement of PHYE in local adaptation between populations of A. nana in northern and southern Japan. This finding is consistent with a previous study on Cardamine nipponica, indicating the importance of PHYE for local adaptation in Japanese alpine plants.  相似文献   

4.
Summary Low alpine Betula nana heaths were studied with regard to plant communities, species distribution, and environmental conditions. It is clear from cluster analyses and PCA-ordinations that the distribution of winter snow is the most important factor for the composition of plant communities and the distribution of most plant populations. Under deep snow conditions soil instability is also important as a differentiating factor.The numerical treatment of data gives a phytosociological grouping in eoncordance with earlier opinions based on stand tabulations.The cluster analysis group the species into chionophobous, chionophilous, moderate snow bed species, and an additional group of wide snow depth amplitude. Only a few species remain unclassified. The ecological species groups are readily identified also in PCA-ordinations. They are independent of differences in species numbers and combinations.Nomenelature follows Lid (1963), Nyholm (1954–1969), Arnell (1956), and Dahl & Krog (1972).I am grateful to Dr. Eddy van der Maarel, University of Nijmegen, for critical comments on the manuseript, to Dr. Ewa Kvillner, University of Lund, and to my colleagues in Göteborg for generous help and encouragement throughout the study, which forms part of a Ph. D. thesis in the University of Göteborg. The work has been supported by grants from The Royal Swedish Academy of Sciences and from the Faculty of Natural Sciences, University of Göteborg.  相似文献   

5.
According to previous phylogeographic studies, high mountains at low latitudes are important areas for the study of the evolutionary history of arctic–alpine plants in surviving the Pleistocene climatic oscillations. To evaluate this hypothesis, we elucidated the genetic structure of the arctic–alpine plant, Loiseleuria procumbens , in the Japanese archipelago, which corresponds to one of the southernmost limits of its distribution, using 152 individuals from 17 populations that covered the entire distribution of the Japanese archipelago and Sakhalin, in addition to samples from Sweden. Based on 854 bp of chloroplast DNA, we detected eight haplotypes. Along with haplotype distribution, strong genetic differentiation between populations in central and northern Japan was elucidated by a neighbour-joining tree (100%) and spatial analysis of molecular variance (79%), which is consistent with other alpine plants in Japan, regardless of the species' range. In addition, the southernmost populations from northern Japan showed specific genetic structure, although the remaining areas of northern Japan and Sakhalin harboured an homogenous genetic structure. Our results suggest that the populations in central Japan persisted for a long time during the Pleistocene climatic oscillation and that genetic divergence occurred in situ , supporting our hypothesis in conjunction with a previous study of another arctic–alpine plant, Diapensia lapponica subsp. obovata .  © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 97 , 403–412.  相似文献   

6.
7.
报道了中国杜鹃花科(Ericaceae)一新记录种:腺苞树萝卜[Agapetes nana(Griff.) Hook. f.]。该种以花萼筒基部具有一圈具柄的腺毛组成的副萼状总苞,花冠筒裂至2/3,裂片反卷而与同属其他种类明显区别。该种原仅分布于印度东北部和缅甸北部,现首次在中国发现其分布。同时,提供了本种的描述和彩色图片,并首次报道成熟的花部形态,凭证标本保存于中国科学院西双版纳热带植物园标本馆(HITBC)。  相似文献   

8.
Summary Two strains ofEeniella nana were examined for their partial base sequences of 18S and 26S rRNAs. In the partial base sequences of 18S rRNA (prositions 1451 through 1618, 168 bases) the strains ofE. nana have five, five, four and eleven base differences with those ofDekkera bruxellensis (type species).D. anomala (andBrettanomyces anomalus),D. naardenensis andD. custersiana, respectively. In the 26S rRNA partial base sequencings (positions 1611 through 1835, 225 bases and positions 493 through 622, 130 bases) the base differences were 46, 43, 34 and 40 and the percent similarities were 53–54, 51–54, 56–57 and 51–53, respectively. The sequence data obtained are discussed phylogenetically and taxonomically, especially on retention of the generic nameEeniella.This paper is dedicated to Professor Herman Jan Phaff in honor of his 50 years of active research which still continues.Significance of the coenzyme Q system in the classification of yeasts and yeast-like organisms. Part LVIII. For part LVII, see ref. [20].  相似文献   

9.
Given that East Asia is located south‐west of Beringia and was less glaciated during the Pleistocene, species at higher latitudes were able to expand their range in this region during climate cooling. Although southward migration is an inevitable colonization process, the biogeographical history of the disjunct ranges of higher‐latitude species in East Asia has been investigated less extensively. Here, we assess whether their disjunct distributions in the Japanese archipelago connected sufficiently with Beringia or persisted in isolation following their establishment. Sequences of nine nuclear loci were determined for Cassiope lycopodioides (Ericaceae) from the Japanese archipelago as well as its surrounding areas, Kamchatka and Alaska. According to the geographical pattern of genetic diversity, the northern populations from Kamchatka to the northern part of the Japanese archipelago were similar genetically and were differentiated from populations in central Japan. Our study suggested that the distribution of C. lycopodioides was connected between the northern part of the Japanese archipelago and south‐western Beringia due to Pleistocene climate cooling. Conversely, central Japan harboured a disjunct range after its establishment. These inferences suggest that widespread range expansion in northern East Asia was plausible for species distributed in Beringia. © 2014 The Linnean Society of London, Biological Journal of the Linnean Society, 2014, 113 , 497–509.  相似文献   

10.
Umbelopsis nana andU. vinacea isolated from soils in Nagano Pref., Japan were redescribed and illustrated.  相似文献   

11.
Phenetic analyses of 218 OTUs belonging toVaccinium sectionMyrtillus and scored for 13 characters generated five robust clusters.Vaccinium parvifolium is the most distinct cluster, followed by the “myrtillus-scoparium” complex, thenV. membranaceum, V. caespitosum, and the “ovalifolium-deliciosum” complex. Biosystematic studies suggest that the five clusters comprise seven taxa that possess many of the properties that define biological species. Indeed, the recognition of the seven taxa as species is supported by cytological, phenological, biogeographical and ecological as well as chemical data. A detailed taxonomic treatment for all these taxa is presented.  相似文献   

12.
In this second report of the present series, six species ofCercospora described in Japan were transferred to the genusPseudocercospora after detailed reexamination. They arePseudocercospora abeliae, P. chionanthi-retusi, P. corylopsidis, P. ehretiae, P. naitoi andP. paulowniae.  相似文献   

13.
Island canaries (Serinus canaria) are characterised as a species living exclusively on North Atlantic islands, mainly on the Azores, Madeira and Canary Islands. Although they are very common in their habitats, their behaviour and breeding system has only recently been studied systematically. To advance the understanding of their ecology and to see if the rather isolated archipelagos are already promoting a genetic differentiation, we investigated their phylogeographic relationship as revealed by mtDNA sequences of the cytochrome b gene and investigated whether this measure corresponds to morphological characteristics within the islands. Genetic distances were very low throughout the distribution range of the species. Although the variation of genetic distances within the population of Pico (Azores) was larger than that on Madeira and Canary Islands, the genetic distances between island populations were very low throughout which prevented a clear phylogeographic differentiation. Moreover, morphological measurements did not reveal a consistent pattern to reliably separate the populations, although the measures of beak length and body weight revealed a clear island-specific differentiation. These data lead to the assumption that the colonisation of the Atlantic islands by the canaries occurred very recently, while there is no persisting gene flow between the populations.  相似文献   

14.
A new dicranophorid rotifer, Encentrum (Parencentrum) walterkostei n.sp., is described from an oligotrophic alpine lake. The species was abundant in the psammolittoral of the Unterer Schwarzhornsee, 2543 m above sea level. The main distinguishing taxonomic features of the new species are long, swordshaped toes and only four vitellary nuclei. Its known occurrence in the sandy substrate of only one lake suggests a stenobiontic nature of this apparently oligothermic new species. Taxonomic problems associated with the Encentrum/Dicranophorus group are briefly discussed.  相似文献   

15.
In the third report of the present series, five species ofCercospora sensu lato described by Japanese mycologists were transferred to the genusPseudocercospora after detailed reexamination. They arePseudocercospora photiniae, P. phrymae, P. stephanandrae, P. vaccini andP. kirishimensis. Pseudocercospora photiniae was retained as an independent species, not regarded as a synonym ofP. eriobotryae.  相似文献   

16.
通过对模式标本和原始文献的研究,确认Vaccinium wardii Adamson 是红粉白珠(Gaultheria hookeri C. B. Clarke)的异名,而不是乌鸦果(Vaccinium fragile Franch.)的异名.  相似文献   

17.
The common or brown shrimp Crangon crangon (L.) is a highly abundant and important taxon, both ecologically and commercially, yet knowledge on its population structure and historical biogeography is limited. We studied population genetic structure across the distribution range of this species by sequencing a 388 bp fragment of the cytochrome-c-oxidase I gene for 140 individuals from 25 locations. Strong population structuring and high levels of genetic diversity were observed. Four main phylogroups were uncovered: northeastern Atlantic, western Mediterranean, Adriatic Sea and Black Sea. Gene flow of these shrimp across known oceanographical barriers (e.g., the Strait of Gibraltar and/or Oran-Almeria front, Sicilian Straits, and Turkish Straits) is severely restricted. The oldest and most variable populations currently inhabit the western Mediterranean. The observed absence of structure across the entire northeastern Atlantic shelf is proposed not to be due to gene flow, but to relatively recent colonization following the glacial cycles of the late Pleistocene. Black Sea shrimp are currently disconnected from Mediterranean populations, and colonization is inferred, on the basis of coalescent analysis, to have happened relatively recently, but possibly earlier than 7000 years ago. We postulate the hypothesis that C. crangon survived the last brackish-water (<7 per thousand) period inside the Black Sea and/or one of the adjacent inland seas. We conclude that (1) common shrimp populations from different basins are strongly differentiated, (2) gene flow across basins is probably very limited, and (3) the biogeographic history of the taxon is largely in accordance with the geographic history of its distribution range. This study provides further evidence that high population connectivity of marine species (e.g., by policy makers) should not be assumed.  相似文献   

18.
Section Vireya (Blume) Copel.f. is one of the most morphologically diverse groups of the genus Rhododendron. Vireyas have a unique distribution for the genus, being predominantly found throughout the Malesian Archipelago. The alpha taxonomy of section Vireya is relatively well understood and taxa are easily distinguished from other rhododendrons by their general appearance. Defining characteristics of the section the possession of seeds with tailed appendages at both ends, the twisting of capsule valves after opening, placentas that separate as thread-like structures from the central axis as the capsule opens are all subject to exceptions. Phylogenetic analyses of two cpDNA regions, psbA-trnH and trnT-trnL intergenic spacers are reported. The results of each analysis were generally congruent, with clades relating strongly to geographic areas. Section Vireya is monophyletic with the inclusion of at least one species of section Rhododendron. Only two of the seven subsections currently circumscribed are monophyletic: Malayovireya Sleumer and Siphonovireya Sleumer. ``Euvireya', all subsections excluding the paraphyletic subsection Pseudovireya, is monophyletic and includes two major clades, one restricted to eastern Malesia and the other to the western and middle Malesia.  相似文献   

19.
Arbutoid mycorrhizae were synthesized in growth pouches between Arbutus menziesii Pursch. (Pacific madrone) and two broad host range basidiomycete fungi, Pisolithus tinctorius (Pers.) Coker and Couch and Piloderma bicolor (Peck) Jülich. P. tinctorius induced the formation of dense, pinnate mycorrhizal root clusters enveloped by a thick fungal mantle. P. bicolor mycorrhizae were usually unbranched, and had a thin or non-existent mantle. Both associations had the well-developed para-epidermal Hartig nets and intracellular penetration of host epidermal cells by hyphae typical of arbutoid interactions. A. menziesii roots developed a suberized exodermis which acted as a barrier to cortical cell penetration by the fungi. Ultrastructurally, the suberin appeared non-lamellar, but this may have been due to the imbedding resin. Histochemical analyses indicated that phenolic substances present in epidermal cells may be an important factor in mycorrhiza establishment. Analyses with X-ray energy dispersive spectroscopy showed that some of the granular inclusions present in fungal hyphae of the mantle and Hartig net were polyphosphate. Other inclusions were either protein or polysaccharides.  相似文献   

20.
The central Sierran tetraploidArctostaphylos mewukka Merriam has been reported to be an allopolyploid originating from the diploid species,A. patula Greene and eitherA. viscida subsp.viscida Parry orA. viscida subsp.mariposa (Dudley)P. V. Wells, although without conclusive evidence. Morphometrics and the verification and determination of chromosome numbers were used to substantiate the evolutionary relationships among these species. A closely related species,Arctostaphylos truei Knight, was also examined using these methods to determine its separability fromA. mewukka. The morphometric analyses support a hypothesis for a polyphyletic origin ofA. mewukka from different races ofA. viscida andA. patula. The chromosomal data, although inclusive, also support this hypothesis. The data do not support the recognition ofA. truei as a taxonomic entity separate fromA. mewukka at the species level.  相似文献   

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