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1.
rbcL sequence data (1324 bp on average). Our analyses indicate (1) that Antitrichia is distantly related to the other members of Leucodontaceae and should be excluded from the family, (2) that Cryphaeaceae form a monophyletic clade, not with Anomodontaceae and Leptodontaceae, but with Leucodontaceae, refuting the placement of Leucodontaceae and Cryphaeaceae in different superfamilies, (3) that Forsstroemia, variously classified in Leucodontaceae, Cryphaeaceae or Leptodontaceae, forms a monophyletic clade with Neckera (Neckeraceae), and (4) that the presumed monophyly of Anomodon and that of Anomodontaceae are not supported. Received 18 September 1999/ Accepted in revised form 27 December 1999  相似文献   

2.
Since the 1990s, increasing populations of a blood feeding land leech (Haemadipsa japonica) have become a serious issue in several Japanese prefectures, and it may be caused by the increases in sika deer (Cervus nippon) populations seen over the last quarter of the century. Therefore, this study aimed to reveal the host animal species of H. japonica using iDNA (vertebrate DNA isolated from invertebrates) and to test the hypothesis that the increasingly widespread distribution of sika deer results in increased H. japonica populations through changes to the host–parasite interface. We amplified mitochondrial DNA 16S ribosome RNA fragments from iDNA isolated from the blood clots of H. japonica collected across Japan. We identified 17 host animal species, including four orders of Mammalia (Carnivora, Artiodactyla, Rodentia, and Lagomorpha) and two orders of Amphibia (Caudata and Anura). The sika deer was the dominant host species of H. japonica. Additionally, the host animal species composition of H. japonica differed according to the presence or absence of sika deer. In the sites where sika deer were not found, Anura (frog) species were the most commonly identified hosts of H. japonica. These results suggest that the increases in H. japonica populations might have occurred via a change in host preference to sika deer. This change might be driven by the increases in sika deer populations and subsequent increase in the frequency that H. japonica uses the sika deer as easy prey, as well as by sika deer providing more reproductive energy per blood meal than blood meal from frog species. The present study suggests that a more widespread distribution of sika deer resulted in an increase in H. japonica through a change in the host–parasite interface. Therefore, management that focuses on decreasing sika deer populations would likely be an effective method for the reduction of H. japonica populations.  相似文献   

3.
 We have developed microsatellite markers (SSRs) applicable to Fagus crenata using the RAHM method and investigated their polymorphisms. We also applied the SSRs in an analysis of a closely related species, F. japonica. Here we describe the isolation and characterization of nine polymorphic microsatellite markers, of which eight are applicable to both species. Among 30 individuals of each of F. crenata and F. japonica we detected a total of 79 and 77 alleles, respectively, with an average of 9.9 and 8.6 alleles per locus. The mean expected heterozygosity (He) was 0.615 (range: 0.216–0.925) in F. crenata and 0.660 in F. japonica (range: 0.259–0.827). The He values were considerably higher than those previously found for isozymes. Paternity exclusion probabilities for multiple loci, calculated over all loci, were extremely high (0.999 and 0.998 in F. crenata and F. japonica, respectively): sufficiently high to study pollen flow in both species. Received: 5 December 1998 / Accepted: 28 December 1998  相似文献   

4.
Alien invasive plants threaten biodiversity, productivity and ecosystem functioning throughout the world. We examined the effect of Fallopia japonica on two native grassland species (Trifolium repens, Lolium perenne). We hypothesized that its negative effects on the native species are dependent on three mechanisms: (i) allelochemicals released and accumulated in soil with a history of invasion, (ii) altered soil biota and (iii) direct resource competition. We measured the response of the native species as the difference in their functional traits when grown under the three conditions. Our results demonstrate that neither allelochemicals nor soil biota from soil with history of F. japonica invasion had measurable effects on either species. Competition with the invader strongly reduced height, biomass and specific leaf area (SLA) of T. repens, while it had a lower effect on L. perenne. Furthermore, our results reveal that F. japonica took advantage of a positive plant–soil and plant–plant interaction. The results show that the prominent mechanism underpinning the invasion success of F. japonica in the grassland was the direct resource competition. This prominent role is also confirmed by the significant interactions between competition, allelochemicals and soil biota from soils with history of invasion of F. japonica on SLA of the native species.  相似文献   

5.
The amount and distribution of mitochondrial (mt) DNA restriction fragment length polymorphism was determined among individual tree samples of two Japanese beech species, Fagus crenata and F.japonica. Individual plants were collected from 16 F. crenata populations throughout the range of the species, and from three F. japonica populations. We detected enough variation to characterize eleven and three chondriome types in F. crenata and F.japonica, respectively. The grouping of beech chondriome types based upon the cladistic analysis of mtDNA polymorphism allowed us to recognize the apparent geographical patterns of mtDIMA diversity: the resulting three main groups occupied distinct geographic areas. This geographic differentiation is likely to reflect the history of the Japanese beech forests after the last glacial period of the Pleistocene. In addition, the mtDNA polymorphism encountered within F. crenata encompassed all the variation observed in F.japonica. Our result suggests the need for re-evaluation of their phylogenetic relationships.  相似文献   

6.
The marine microalga Fibrocapsa japonica Toriumi and Takano (Raphidophyceae) produces haemolysins, neurotoxins and reactive oxygen species (ROS). To quantify potential effects of such bioactive compounds on surrounding organisms the marine bacterium Vibrio fischeri was exposed to F. japonica culture samples. Inhibition of V. fischeri ‘s natural luminescence, indicative of impaired metabolism, was related to the number of F. japonica cells added. The effect was fast, within 15 min. It was caused by one, possibly several, excreted substances that were less active after heating. Freezing of culture supernatant partly inactivated these substances, but ROS-scavenging enzymes had no effect. Light enhanced the V. fischeri luminescence inhibition in two ways. The direct effect of light on the action of F. japonica luminescence inhibiter(s) could be described by a saturation curve with maximum effect above 20 μmol photons m−2 s−1. Light also had an indirect effect: biomass production, dependent on light availability, was closely related to the amount of inhibiting compound(s) produced by the alga. Algal growth rate, rather than its cell density, determined the bacterial luminescence inhibition per F. japonica cell, resulting in a 5-fold stronger inhibition at maximum growth rates compared to cells that barely grew during the stationary growth phase. The bioassay with F. japonica and V. fischeri has allowed quantification of the negative effects on bacteria in the microalgal microenvironment. The results presented here suggest that at favourable growth conditions F. japonica releases bioactive compounds that improve its competitive abilities.  相似文献   

7.
Morphometric and genetic analyses were performed to investigate the relationships between populations of the azure‐winged magpie (Cyanopica cyanus). In the morphometric analysis 193 specimens were included representing seven of the nine currently accepted subspecies. Among eight characters analysed, four showed significant differences between samples from Spain and Asia. In contrast, the Asian populations/subspecies are not differentiated morphologically except Cyanopica cyanus japonica. The genetic analysis was based on two mitochondrial sequences (control region, cytochromeb gene). The results are in accordance with the morphometric analysis, showing a clear distinction between birds from the western and eastern distribution ranges. The differentiation of C. c. japonica is not found at the sequence level. Both genetic and morphological data support species status of C. cyanus and Cyanopica cooki. The magpie (Pica pica) was included in the phylogenetic study for comparing intraspecific variation. As in C. cyanus, two clearly separated groups are found, one of them containing the far‐eastern populations (Pica pica jankowskii and Pica pica sericea) and the other the remaining subspecies studied. For both the azure‐winged magpie and the magpie the sequence data imply an east–west differentiation, probably caused by long lasting isolation that may have even started in the Pliocene or repeated expansions/restrictions of distribution ranges during the Pleistocene.  相似文献   

8.
We examined the floral morph of tetraploid Ophiorrhiza japonica Blume var. amamiana Hatus. and diploid O. japonica var. japonica to elucidate the association of distyly and ploidy levels. Chloroplast DNA phylogeny was reconstructed to determine the number of tetraploidization events and floral morph shifts in O. japonica. All individuals of O. japonica var. amamiana proved to be long-homostylous, whereas O. japonica var. japonica was distylous with typical long- and short-styled flowers. Distyly is related to the ploidy level. The bagging treatment of flowers indicated that O. japonica var. amamiana is self-compatible and potentially automatically self-pollinating. In cpDNA sequencing analysis, no haplotype was shared between the two varieties. The cpDNA haplotype network displayed the monophyly of O. japonica var. amamiana, suggesting a single origin of this variety. Hence, both tetraploidization and the breakdown of distyly to homostyly in O. japonica var. amamiana likely occurred just once. Because O. japonica var. amamiana having the morphological and cytological entity is recognized as a single lineage and clearly separated from O. japonica var. japonica, this variety can be considered to be a distinct species. We therefore propose to raise O. japonica var. amamiana to the rank of species. Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users.  相似文献   

9.
We have examined morphological and chromosomal variation inFallopia sect.Reynoutria in Korea to clarify their taxonomic identities and to determine whether their morphological variability is associated with ploidy levels. Principal components analysis (PCA) of individuals from 21 populations, using major distinguishing characters, revealed the presence of four major entiries of sect.Reynoutria in Korea; these includeF. sachalinensis, F. japonica var.japonica, F. forbesii, and the Nonsan population consisting of presumed hybrids. Based on morphology, it is hypothesized that the Nonsan population was probably derived from multiple hybridization events involving the three named taxa. The results also indicate thatF. forbesii is distinct fromF. japonica var.japonica. Polyploidy is more prevalent in sect.Reynoutria than has been previously recognized.Fallopia sachalinensis in Korea occurs as dodecaploids with 2n=132; our count is the first dodecaploid count for the species, and represents the highest chromosome number known in the genus.Fallopia japonica var.japonica occurs as tetraploids (2n=44), hexaploids (2n=66), and octoploids (2n=88), whileF. forbesii occurs as hexaploids (2n=66) and octoploids (2n=88); our counts appear to be the first reported chromosome numbers forF. forbesii. Morphological analysis indicates that there is no apparent correlation between the ploidy levels in these taxa and the morphological characters that we have considered in this study except that the tetraploids ofF. japonica var.japonica tend to have somewhat thicker leaves.  相似文献   

10.
Anania coronata (Hufnagel), a Holarctic species of pyraustine crambid moth, has long been treated as having two geographically separated subspecies – the nominotypical Anania coronata in the Palaearctic Region and Anania coronata tertialis (Guenée) in the Nearctic Region. Maximum likelihood and Bayesian inference analysis of mitochondrial DNA barcodes both recover four well‐supported, reciprocally monophyletic groups within Anania coronata. Qualitative and quantitative analyses of genital structures reveal diagnostic differences that correspond to the four barcode lineages. On the basis of both molecular and morphological evidence, we conclude that Anania coronata is actually a complex of four species. Anania coronata (Hufnagel) is restricted to Europe, whereas three species occur in North America: Anania tertialis (Guenée), Anania plectilis (Grote & Robinson) and Anania tennesseensis sp.n. Yang.  相似文献   

11.
Habitat patch colonization dynamics and distribution patterns were analysed at a landscape scale in four invasive Fallopia (Polygonaceae) species. Fallopia sachalinensis and F. aubertii were uncommon and population expansion was not evident during the three consecutive years of study. The two most widespread species, F. japonica and F. × bohemica displayed similar habitat selection patterns with ruderal and natural/semi-natural forests favoured. The highest densities of F. japonica and F. × bohemica individuals were at the edge of preferred habitat patches with different patterns of edge selection. Linear network played an important role in species invasion, with 71% of all F. japonica and F. × bohemica occurring within a 10 m buffer of total linear networks (roads, railways, and rivers). However, the buffer represented only 14.5% of the total landscape surface. The rate of population increase was higher for F. japonica (75.8% and 35.2%, in 2002 and 2003, respectively) than for F. × bohemica (63.6% and 0% in 2002 and 2003, respectively) and was largely the result of intra-patch dynamics with low inter-patch colonization. The total surface area occupied by Fallopia clones in the landscape grew by 34.7% over 2 years of the study, with comparable area growth means for F. japonica and F. × bohemica (34.9% and 34.7%, respectively). The hypothesis that F. × bohemica exhibits higher invasive dynamics due to both clonal and sexual reproduction was not supported by our results.  相似文献   

12.
Survey of seven strains determined as Septonema ochraceum (Dothideomycetes, inc. sed.) isolated from pine litter or obtained from public collections revealed three new species, Fusicladium cordae, F. sicilianum (Venturiaceae), Cladophialophora matsushimae (Herpotrichiellaceae) and a cryptic species morphologically identical to Devriesia americana (Teratosphaeriaceae), but phylogenetically distinct. Morphological survey and phylogenetic analysis using nucleotide sequence data from the nuclear ribosomal subunit genes indicate a close relationship within three species colonising pine litter needles, F. cordae, F. pini and F. ramoconidii. F. sicilianum is most related to F. rhodense. C. matsushimae represents a species belonging to one of the lineages of the polyphyletic genus Cladophialophora. None of the strains observed can be classified morphologically as S. ochraceum, of which the type material does not exist.  相似文献   

13.
Essl F. 2005. Spread and incipient naturalization of Spiraea japonica in Austria. Bot. Helv. 115: 1–14.The subspontaneous spread and incipient naturalization of the alien Japanese honeysuckle (Spiraea japonica) in Austria were studied by reviewing floristic literature and by surveying a 3-km2 area in the alpine foothills of eastern Upper Austria between 1990 and 2004. The literature review shows that the abundance and range of Spiraea japonica have increased in Austria during the 20th century: Until 1945, the species had been recorded in only three mapping units (c. 30 km2) of the floristic mapping project of Austria. Between 1945 and 1990, it was found in seven mapping units, and since 1991, in a total of 20 mapping units. In the field survey, 50 individuals of Spiraea japonica were recorded in 1990, but 198 in 2004. The species mainly occurred in climax forests (Galio sylvatici-Carpinetum) and pioneer forests (Sambucetum racemosae) dominated by Betula pendula; it was less frequent in pine or spruce plantations. No detrimental effects on native plants could be observed. Nevertheless, the further expansion of Spiraea japonica in Central Europe should be monitored attentively as this species is considered invasive in parts of North America.Manuskript angenommen am 13. November 2004  相似文献   

14.
15.
Japanese knotweed s.l. comprises Fallopia japonica, F. sachalinensis, F. × bohemica and any F2s or backcrosses. The parental taxa were introduced from the East to the West as garden ornamentals in the nineteenth century, and soon spread beyond the confines of the garden to become widespread and persistent weeds. Since only female F. japonica var. japonica was introduced, its impressive spread has occurred solely by vegetative means. However, the initial lack of genetic variability has been complemented by an extensive series of hybridisations in the adventive range. We examine the history, spread, reproductive biology and ecological impact of these species in the West. The role and importance of polyploidy and hybridisation in their invasion of the West is discussed, as are the implications of these factors for the potential further evolution of the group.  相似文献   

16.
Using dendrochronological techniques, this study examined whether tree-ring width of two evergreen broad-leaved species (Cleyera japonica, Eurya japonica) at their inland northern distribution limit in central Japan is more limited by low temperature compared with two co-dominating deciduous broad-leaved species (Fagus japonica, Magnolia hypoleuca) and two evergreen conifer species (Chamaecyparis obtusa, Abies firma), whose distribution limits are further north. The two deciduous broad-leaved species and the two evergreen conifers are tall tree species. Evergreen broad-leaved Cleyera japonica is a sub-canopy species and Eurya japonica is a small tree species. The tree-ring widths of four of the six species (except for Eurya japonica and Magnolia hypoleuca) correlated positively with the March temperature just before the start of the growth period. For deciduous broad-leaved Magnolia hypoleuca, the tree-ring width was correlated positively and negatively with July temperature and precipitation, respectively. However, the other deciduous broad-leaved Fagus japonica showed no such relationships. For the evergreen broad-leaved Cleyera japonica and evergreen conifers Chamaecyparis obtusa and Abies firma, tree-ring widths correlated positively with winter temperatures, probably because evergreen species can assimilate during warm winters. The tree-ring width of Cleyera japonica also correlated positively with temperatures of many months of the growth period. By contrast, the tree-ring width of the other evergreen broad-leaved Eurya japonica showed no positive correlation with the temperature in any month. Most Eurya japonica trees were suppressed by tall trees, which might disguise any climate effect. Thus, there were species differences in response to climate for each life form, and the tree-ring width of Cleyera japonica at the northern distribution limit was more limited by low temperatures compared with co-dominating species. It is suggested that growth of Cleyera japonica is increased by global warming at the latitudinal ecotone.  相似文献   

17.
Negative interactions between non-indigenous and native species has been an important research topic of invasion biology. However, interactions between two or more invasive species may be as important in understanding biological invasions, but they have rarely been studied. In this paper, we describe three field experiments that investigated interactions between two non-indigenous plant species invasive in the eastern United States, Lonicera japonica (a perennial vine) and Microstegium vimineum (an annual grass). A press removal experiment conducted within a deciduous forest understory community indicated that M. vimineum was a superior competitor to L. japonica. We tested the hypothesis that the competitive success of M. vimineum was because it overgrew, and reduced light available to, L. japonica, by conducting a separate light gradient experiment within the same community. Shade cloth that simulated the M. vimineum canopy reduced the performance of L. japonica. In a third complementary experiment, we added experimental support hosts to test the hypothesis that the competitive ability of L. japonica is limited by support hosts, onto which L. japonica climbs to access light. We found that the abundance of climbing branches increased with the number of support hosts. Results of this experiment indicate that these two invasive species compete asymmetrically for resources, particularly light.  相似文献   

18.
Fallopia japonica (Houtt.) Ronse Decraene is an invasive plant species that introduces economic, social, and environmental stresses. After observing frost damage to F. japonica plants in the field, we exposed leaves of F. japonica and a native species (Acer saccharum Marshall) to freezing temperatures in the laboratory and compared their net photosynthetic rate to that of fresh leaves. In both species, the net photosynthetic rate of leaves frozen for 0.5 h or for 1 h were not significantly different from each other but were both significantly less than that of fresh leaves. Fresh leaves of F. japonica had a higher net photosynthetic rate than those of A. saccharum, but the relationship was reversed in all freezing treatments. Frozen leaves of F. japonica contained microscopically visible frost lenses, which revealed the mechanism of the damage. These results quantify how quickly F. japonica is damaged by freezing conditions and suggest that minimum vernal temperatures may limit its range expansion.  相似文献   

19.
20.
Two free‐living marine euplotid ciliates, Pseudodiophrys nigricans and Diophrys japonica, collected from the coastal waters off Qingdao, northern China, were investigated using live observations and protargol impregnation methods. The cortical development of P. nigricans was observed during binary division. Although its general pattern of morphogenesis is similar to that of other Diophrys‐like species, three unusual features are noteworthy: 1) the frontoventral transverse cirral anlagen develop in the secondary mode, similar to that of Euplotes; 2) the undulating membrane anlage migrates far from the cytostome and does not split into two membranes; and 3) the parental adoral zone of membranelles remains nearly intact throughout the entire morphogenetic process. Diophrys japonica is redescribed based on a Chinese population and can be recognized by having one left marginal cirrus, densely arranged cortical granules, and a fragment kinety with three dikinetids. Phylogenetic analyses based on the small subunit rRNA (SSU rRNA) gene sequence data indicate that D. japonica is placed within the Diophrys clade and is most closely related to the well‐known D. apoligothrix. © J. Morphol., 2013. © 2012 Wiley Periodicals, Inc.  相似文献   

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