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1.
Jitka Štěpánková 《Folia Geobotanica》1993,28(2):113-128
In 74 natural populations of theMyosotis palustris andM. laxa groups from former Czechoslovakia three euploid and one aneuploid cytotypes were found that belong to the following species:M. nemorosa Besser, 2n=22,M. palustris (L.)Nath. em.Reichenb. inSturm, 2n=66,M. laxiflora Reichenb., 2n=66,M. radicans Opiz, 2n=66(64),M. brevisetacea (Schuster) Holub, 2n=66(64), andM. caespitosa C.F. Schultz, 2n=88. With the exception ofM. nemorosa, the chromosome numbers are published for the first time for the Czech Republic. The chromsome numbers, 2n=66, 2n=64 are found inM. brevisetacea, are new for the literature. The correlation between pollen size and ploidy level has been studied as well, and statistically significant differences were found between cytotypes belonging to different ploidy levels. 相似文献
2.
BACKGROUND AND AIMS: Pilosella officinarum (syn. Hieracium pilosella) is a highly structured species with respect to the ploidy level, with obvious cytogeographic trends. Previous non-collated data indicated a possible differentiation in the frequency of particular ploidy levels in the Czech Republic and Slovakia. Therefore, detailed sampling and ploidy level analyses were assessed to reveal a boundary of common occurrence of tetraploids on one hand and higher ploids on the other. For a better understanding of cytogeographic differentiation of P. officinarum in central Europe, a search was made for a general cytogeographic pattern in Europe based on published data. METHODS: DNA-ploidy level and/or chromosome number were identified for 1059 plants using flow cytometry and/or chromosome counting on root meristem preparations. Samples were collected from 336 localities in the Czech Republic, Slovakia and north-eastern Hungary. In addition, ploidy levels were determined for plants from 18 localities in Bulgaria, Georgia, Ireland, Italy, Romania and Ukraine. KEY RESULTS: Four ploidy levels were found in the studied area with a contrasting pattern of distribution. The most widespread cytotype in the western part of the Czech Republic is tetraploid (4x) reproducing sexually, while the apomictic pentaploids and mostly apomictic hexaploids (5x and 6x, respectively) clearly prevail in Slovakia and the eastern part of the Czech Republic. The boundary between common occurrence of tetraploids and higher ploids is very obvious and represents the geomorphologic boundary between the Bohemian Massif and the Western Carpathians with the adjacent part of Pannonia. Mixed populations consisting of two different ploidy levels were recorded in nearly 11% of localities. A statistically significant difference in a vertical distribution of penta- and hexaploids was observed in the Western Carpathians and the adjacent Pannonian Plain. Hexaploid populations tend to occur at lower elevations (usually below 500 m), while the pentaploid level is more or less evenly distributed up to 1000 m a.s.l. For the first time the heptaploid level (7x) was found on one site in Slovakia. In Europe, the sexual tetraploid level has clearly a sub-Atlantic character of distribution. The plants of higher ploidy level (penta- and hexa-) with mostly apomictic reproduction prevail in the northern part of Scandinavia and the British Isles, the Alps and the Western Carpathians with the adjacent part of Pannonia. A detailed overview of published data shows that extremely rare records on existence of diploid populations in the south-west Alps are with high probability erroneous and most probably refer to the closely related diploid species P. peleteriana. CONCLUSIONS: The recent distribution of P. officinarum in Europe is complex and probably reflects the climatic changes during the Pleistocene and consequent postglacial migrations. Probably both penta- and hexaploids arose independently in central Europe (Alps and Carpathian Mountains) and in northern Europe (Scandinavia, Great Britain, Ireland), where the apomictic plants colonized deglaciated areas. We suggest that P. officinarum is in fact an amphidiploid species with a basic tetraploid level, which probably originated from hybridizations of diploid taxa from the section Pilosellina. 相似文献
3.
Vladimír Antonín Michal Tomšovský Petr Sedlák Tomáš Májek Libor Jankovský 《Mycological Progress》2009,8(3):259-271
Armillaria cepistipes and A. gallica (Basidiomycota, Physalacriaceae) are morphologically similar species, and they are often nearly indistinguishable using DNA-based methods targeting the ITS
region of ribosomal DNA. The aim of this study was to examine morphological and ecological features of A. cepistipes and A. gallica, and to test other DNA-based methods to distinguish the two species. Our results revealed discriminative macro- and micromorphological
features between these two species, especially the presence of a distinct central pileus ocella, the shape of the annulus,
the character of the velar stipe remnants and the length of the terminal cells of the pileus scales. Ecologically, A. gallica generally prefers warmer areas in lowlands (oak and alluvial forests), while A. cepistipes is more common in hilly and lower montane beech forests in Central Europe. Nevertheless, despite differences in ecological
preferences, certain locations between 300 and 500 m a.s.l. are known to sympatrically support both species. The sequences
of the translation elongation factor 1-alpha showed high interspecific variability, and this gene is a more appropriate candidate
for distinguishing A. gallica from A. cepistipes. 相似文献
4.
Daniel R. Schlaepfer Peter J. Edwards John C. Semple Regula Billeter 《Journal of Biogeography》2008,35(11):2119-2127
Aim Newly formed polyploids experience problems of establishment and spread similar to those faced by newly introduced alien species. To understand the significance of polyploidy in biological invasions, we mapped the distribution of ploidy levels in Solidago gigantea Aiton in its native range in North America, and in Europe and East Asia where it is invasive. Location North America, Europe and East Asia. Methods Flow cytometry was used to measure ploidy levels in a total of 834 plants from 149 locations. Together with data from contributors and a literature review, ploidy‐level data were assembled for 336 locations. Cytogeographical maps from North America and Europe were prepared, incorporating new and previously published ploidy‐level data. Results In the native range, diploid, tetraploid and hexaploid plants were found, and also one triploid and one pentaploid plant (2n = 3x and 2n = 5x, respectively, each being new reports for this species). There was a high degree of geographical separation among the ploidy levels, and populations with mixed ploidy were rare. However, four zones were identified where plants of different ploidy could come into contact. In Europe and East Asia, only tetraploid plants were found. Main conclusions The geographical pattern in North America suggests that the ploidy levels are ecologically differentiated, although further investigations are needed to identify the nature of these differences. Alien populations appear to be exclusively tetraploid, but it is not clear whether this is because tetraploids were selectively introduced or because diploids were unsuccessful. In any case, comparisons between native and introduced populations need to account for ploidy level. 相似文献
5.
Luca F Di Giacomo F Benincasa T Popa LO Banyko J Kracmarova A Malaspina P Novelletto A Brdicka R 《American journal of physical anthropology》2007,132(1):132-139
To analyze the contribution of the Czech population to the Y-chromosome diversity landscape of Europe and to reconstruct past demographic events, we typed 257 males from five locations for 21 UEPs. Moreover, 141 carriers of the three most common haplogroups were typed for 10 microsatellites and coalescent analyses applied. Sixteen Hg's characterized by derived alleles were identified, the most common being R1a-SRY(10831) and P-DYS257*(xR1a). The pool of haplogroups within I-M170 represented the third most common clade. Overall, the degree of population structure was low. The ages for Hg I-M170, P-DYS257*(xR1a), and R1a-SRY(10831) ap peared to be comparable and compatible with their presence during or soon after the LGM. A signal of population growth beginning in the first millennium B.C. was detected. Its similarity among the three most common Hg's indicated that growth was characteristic for a gene pool that already contained all of them. The Czech population appears to be influenced, to a very moderate extent, by genetic inputs from outside Europe in the post-Neolithic and historical times. Population growth postdated the archaeologically documented introduction of Neolithic technology and the estimated central value coincides with a period of repeated changes driven by the development of metal technologies and the associated social and trade organization. 相似文献
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Several theoretical approaches have been proposed to explain variation in religiosity, including versions of secularization hypotheses, evolved cognitive biases, and cultural transmission. In this paper we test several theories that aim to explain variation in religiosity and compare them in a representative sample collected in the Czech Republic and Slovakia (N = 2022). These two countries represent a natural experiment in religiosity; despite their high level of historical, institutional and cultural similarity, their populations differ markedly in the rate of religious belief. We examine the predictive power of cognitive biases (anthropomorphism, dualism, teleology, mentalizing, and analytic thinking); institutional insecurity; and exposure to credibility displays of belief in childhood on various factors of religious belief. We find that individual differences in cognitive biases predicted 8% of the variance belief in God, but predicted 21% of the variance in paranormal beliefs and almost no variance in religious participation. Perceived institutional insecurity explains little variance in any of these variables, but cultural transmission, measured as exposure to credibility enhancing displays (CREDs) and church attendance in childhood, predicted 17% of the variance in belief in God and 30% of religious participation, and mediated 70% of the difference between these two countries in belief in God and 80% of the difference in religious practice. These findings suggest cognitive biases may explain the existence of belief in the supernatural generally, but cultural transmission through credible belief displays is a more plausible explanation for why people adopt and maintain a specific set of religious beliefs and practices. 相似文献
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Morphological variation of the introduced perennial Solidago canadensis L. sensu lato (Asteraceae) in Europe 总被引:1,自引:0,他引:1
EWALD WEBER 《Botanical journal of the Linnean Society. Linnean Society of London》1997,123(3):197-210
Morphological and life-history variation within and between 23 European populations of the introduced and widespread perennial Solidago canadensis L. sensu lato (Asteraceae) was investigated. The populations differed significantly in all 19 characters measured. Coefficients of variation and intraclass-correlations were high for characters related to growth. Floral characters (involucral height, number of disk florets, number of ray florets), and pubescence of stems and leaves varied considerably among sampled shoots, but their frequency distributions were unimodal and the coefficients of variation low. The first three principal components explained 48% of the variation and formed no dusters among the shoots. Several character means correlated with latitude, indicating clinal variation among the populations. Comparison of variation in floral and leaf characters with data from the native range suggests that S. canadensis s.l. naturalized in Europe belongs to a taxon that is close to S. canadensis var. scabra (Muhl.) Torr. & Gray ( S. altissima L.), despite the reported diploid chromosome number of this taxon in Europe. 相似文献
11.
Zdeňka Lososová Milan Chytrý Šárka Cimalová Zdenka Otýpková Petr Pyšek Lubomír Tichý 《Folia Geobotanica》2006,41(3):259-273
Numerical classification of 2653 geographically stratified relevés of weed vegetation from the Czech and Slovak Republics was performed with cluster analysis. Diagnostic species were determined for each of the seven main clusters using statistical measures of fidelity. The classification reflected clear distinctions between lowland (mostly calcicole) and highland (mostly calcifuge) sites, spring and summer phenological stages, and cereals and root crops. The results of the cluster analysis were compared with traditional phytosociological units. Two clusters corresponded to calcifuge weed vegetation of theScleranthion annui alliance; one cluster represented the vegetation of root crops on moist soils of theOxalidion europaeae alliance; one cluster contained thermophilous weed vegetation of theCaucalidion lappulae alliance; two clusters included weed vegetation of root crops and of stubble fields, which can be assigned to theCaucalidion, Panico-Setarion,Veronico-Euphorbion andEragrostion alliances; one cluster included vernal weed vegetation in little disturbed habitats of theCaucalidion lappulae andScleranthion annui alliances. Our analysis did not support the concept of theSherardion andVeronico-Taraxacion alliances, which were included in earlier overviews of the vegetation units of the Czech Republic and Slovakia. 相似文献
12.
Micromorphological and anatomical characters of two Achillea L. species, A . phrygia Boiss. & Bal. and A. gypsicola Hub-Mor., which are endemic to Turkey, were investigated. It was observed that stem length, corymb width, number of capitula and median phyllary shape were diagnostic characters. In the anatomical studies, cross sections were taken from roots, stem and leaves. It was observed that roots of the investigated taxa had a secondary thickening. Endodermis and collenchyma layers were prominent in the stem of both taxa and they had a bifacial mesophyll while the layers of the mesophyll varied. Stomata were anomocytic in both species. We found that there was a significant difference in terms of width of epidermis cells and length of cortex cells in the root, epidermis width and length, collenchyma and parenchyma cells, endodermis length, diameter of trachea of stem, length of upper epidermis cells, width of lower epidermis cells, length of palisade parenchyma and spongy parenchyma cells, diameter of trachea and stomata length of leaf between the two taxa (p<0.05). Scanning electron microscopy (SEM) was used to describe the micromorphology of trichomes and achenes. In A. phrygia , long and eglandular trichomes were more dense on the stem and leaf epidermis. Achene micromorphological characteristics such as size, shape and achene coat were considered to be useful in separating the investigated species. 相似文献
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The 1997 check list of Dolichopodidae of the Czech Republic and Slovakia has recently been reviewed and updated. The new species
list includes 346 species with 22 species added as new to the fauna of the Czech Republic. While the check list itself is
published elsewhere, largely unpublished new records of Hercostomus argentifrons, H. nigrilamellatus, Medetera adjaniae, M. melancholica and M. setiventris are presented here, together with data on their distribution in Europe and their biology and ecology. The status of the newly
added Sympycnus desoutteri is discussed. H. argentifrons is recorded here for the first time from the Czech Republic (Bohemia; Moravia) and background information is given on its
discovery. While the Czech fauna with 324 species can be considered well known, the fauna of Slovakia is definitely much richer
than its current national list of 217 species suggests. In the latter country, in particular surveys of sandy habitats with
heathland or peatmoor, saltmarshes, reedmarshes, humid forests on loamy soils, and of rothole and saprun microhabitats on
trees might quickly yield new species records. 相似文献
15.
Martínková N Bačkor P Bartonička T Blažková P Cervený J Falteisek L Gaisler J Hanzal V Horáček D Hubálek Z Jahelková H Kolařík M Korytár L Kubátová A Lehotská B Lehotský R Lučan RK Májek O Matějů J Rehák Z Šafář J Tájek P Tkadlec E Uhrin M Wagner J Weinfurtová D Zima J Zukal J Horáček I 《PloS one》2010,5(11):e13853
Background
White-nose syndrome is a disease of hibernating insectivorous bats associated with the fungus Geomyces destructans. It first appeared in North America in 2006, where over a million bats died since then. In Europe, G. destructans was first identified in France in 2009. Its distribution, infection dynamics, and effects on hibernating bats in Europe are largely unknown.Methodology/Principal Findings
We screened hibernacula in the Czech Republic and Slovakia for the presence of the fungus during the winter seasons of 2008/2009 and 2009/2010. In winter 2009/2010, we found infected bats in 76 out of 98 surveyed sites, in which the majority had been previously negative. A photographic record of over 6000 hibernating bats, taken since 1994, revealed bats with fungal growths since 1995; however, the incidence of such bats increased in Myotis myotis from 2% in 2007 to 14% by 2010. Microscopic, cultivation and molecular genetic evaluations confirmed the identity of the recently sampled fungus as G. destructans, and demonstrated its continuous distribution in the studied area. At the end of the hibernation season we recorded pathologic changes in the skin of the affected bats, from which the fungus was isolated. We registered no mass mortality caused by the fungus, and the recorded population decline in the last two years of the most affected species, M. myotis, is within the population trend prediction interval.Conclusions/Significance
G. destructans was found to be widespread in the Czech Republic and Slovakia, with an epizootic incidence in bats during the most recent years. Further development of the situation urgently requires a detailed pan-European monitoring scheme. 相似文献16.
Ales Tichopad Craig Roberts Igor Gembula Petr Hajek Anna Skoczynska Waleria Hryniewicz Karina Jahnz-Rozyk Roman Prymula Ivan Solovi? Vitězslav Kolek 《PloS one》2013,8(8)
We estimate and describe the incidence rates, mortality, and cost of CAP (community-acquired pneumonia), in both inpatient and outpatient settings, in the Czech Republic (CZ), Slovakia (SK), Poland (PL), and Hungary (HU). A retrospective analysis was conducted on administrative data from the health ministry and insurance reimbursement claims with a primary diagnosis of pneumonia in 2009 to determine hospitalization rates, costs, and mortality in adults ≥50 years of age. Patient chart reviews were conducted to estimate the number of outpatient cases. Among all adults ≥50 years, the incidence of hospitalized CAP per 100,000 person years was: 456.6 (CZ), 504.6 (SK), 363.9 (PL), and 845.3 (HU). The average fatality rate for all adults ≥50 is 19.1%, and for each country; 21.7% (CZ), 20.9% (SK), 18.6% (PL), 17.8% (HU). Incidence, fatality, and likelihood of hospitalization increased with advancing age. Total healthcare costs of CAP in EUR was 12,579,543 (CZ); 9,160,774 (SK); 22,409,085 (PL); and 18,298,449 (HU); with hospitalization representing over 90% of the direct costs of treatment. The burden of CAP increases with advancing age in four CEE countries, with hospitalizations driving the costs of CAP upwards in the elderly population. Mortality rates are generally higher than reported in Western EU countries. 相似文献
17.
CAMILLA SØNDERBERG BROK HENNING ADSERSEN 《Botanical journal of the Linnean Society. Linnean Society of London》2007,154(4):523-544
Representative samples were collected from almost all known populations of the endemic Galapagos genus Lecocarpus. Multivariate statistical methods were applied to morphological characters to investigate differentiation among species and populations. In discriminant analysis no misclassifications were made among species. Populations of L. darwinii and L. lecocarpoides were better discriminated than populations of L. pinnatifidus . Principal Component Analysis (PCA) separated species well although intermediate populations occur between L. darwinii and L. lecocarpoides . Clear patterns of within-species differentiation were seen among populations of L. darwinii and L. lecocarpoides , but not among populations of L. pinnatifidus .
Populations of L. lecocarpoides at present grow on separate islands. All populations of L. darwinii are found on San Cristóbal, but this island might have been separated into more islands in the past. Lecocarpus pinnatifidus has probably always been growing on only one island. This suggests that the sea is the major barrier to dispersal of the three species. We find it likely that the degree of reproductive isolation caused by the sea is crucial to the differentiation among populations, and that genetic drift rather than adaptation has been responsible. The analyses cast new light on the identity of classic collections made by Darwin in 1835 and Stewart in 1906. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 523–544. 相似文献
Populations of L. lecocarpoides at present grow on separate islands. All populations of L. darwinii are found on San Cristóbal, but this island might have been separated into more islands in the past. Lecocarpus pinnatifidus has probably always been growing on only one island. This suggests that the sea is the major barrier to dispersal of the three species. We find it likely that the degree of reproductive isolation caused by the sea is crucial to the differentiation among populations, and that genetic drift rather than adaptation has been responsible. The analyses cast new light on the identity of classic collections made by Darwin in 1835 and Stewart in 1906. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society , 2007, 154 , 523–544. 相似文献
18.
This study includes 24 reports of chromosome counts in Tripleurospermum Sch. Bip. (20 taxa), Anthemis L. (1 species) and Matricaria L. (3 taxa) belonging to the tribe Anthemideae of the family Asteraceae from Turkey. Chromosome numbers of these taxa are 2n = 2x = 18, 3x = 27 and 4x = 36. Nine counts are new reports, one is not consistent with previous report, and the remainder confirm earlier information. Statistically significant differences depending on ploidy level, stomatal length or environmental factors such as altitude were determined in Tripleurospermum. Several systematic and evolutionary aspects of the genera are discussed in the light of chromosomal data. 相似文献
19.
The DNA ploidy level of 673 accessions belonging to 238 species of Hieracium have been analyzed by flow cytometry. 222 of the species were of Scandinavian origin as members of the exclusively apomictic H. sectt. Bifida, Hieracium, Oreadea, Tridentata and Vulgata. For the overwhelming majority of the species, the ploidy level (or chromosme number) has never been investigated before. Approximately 50% of the Scandinavian species, previously believed to be exclusively triploid, were found to be tetraploid. In addition, two pentaploid samples, viz. H. intermarginatum Johanss. & Sam. from Sweden and H. cf. plumbeum Blytt & Fr. from Germany, were found. Although two or more accessions from geographically remote sites were analyzed for approximately 50% of the Scandinavian species, only 2 (<2%) taxonomically undisputed species were found to consist of plants with more than one ploidy level. An intriguing pattern was revealed among Scandinavian members of H. sectt. Bifida and Vulgata when ploidy level and morphometric variation was compared, viz. the most typical or extreme representatives of these sections were found to be exclusively triploid whereas tetraploids dominate among species with intermediate morphology and among species morphologically intermediate between these sections and H. sect. Hieracium. This pattern may indicate that the tetraploids, which tend to have mainly northern distributions, have originated as the result of rare sexual hybridizations between triploid members of different sections, plausibly during or after the northward migration of the parental linages after the last glaciation. The results are believed to be highly relevant for understanding the processes of evolution and speciation within the predominantly apomictic genus Hieracium, but it is emphazised that additional data from e.g. molecular markers and pollen viability analysis are needed before any trustworthy conclusions can be made as far as evolutionary processes are concerned. 相似文献
20.
BOHUMIL MANDÁK PETR ZÁKRAVSKÝ DANA KOÍNKOVÁ PETR DOSTÁL IVANA PLAKOVÁ 《Biological journal of the Linnean Society. Linnean Society of London》2009,98(3):596-607
Colonizing species are predicted to suffer from reductions in genetic diversity during founding events. Although there is no unique mode of reproduction that is characteristic of successful plant colonizers, many of them are predominantly self-fertilizing or apomictic species, and almost all outcrossing colonizers are self-compatible. Carduus acanthoides comprises a species of disturbed habitats with wind-dispersed seeds that colonizes open spaces of various sizes. Population genetic diversity was expressed by assessing patterns of variation at nine putatively neutral allozyme loci within and among 20 natural populations in its native distribution range in the Czech Republic. Overall, C. acanthoides displayed high levels of genetic diversity compared to other herbaceous plants. The percentage of polymorphic loci was 84.5, with values of 2.37, 0.330, and 0.364 for the mean number of alleles per polymorphic locus ( A ), observed heterozygosity ( H o ), and expected heterozygosity ( H e ), respectively. There was only weak evidence of inbreeding within populations ( f = 0.097) and very low genetic differentiation among populations ( θ = 0.085). Analyses of the data provide strong evidence for isolation-by-distance for the whole study area. Even the colonizing species, C. acanthoides , currently supports a substantial amount of allozyme variation at both the species and population levels. © 2009 The Linnean Society of London, Biological Journal of the Linnean Society , 2009, 98 , 596–607. 相似文献