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2. Catalogue of alien plants of the Czech Republic (2nd edition): checklist update, taxonomic diversity and invasion patterns
- Creator:
- Pyšek, Petr, Danihelka, Jiří, Sádlo, Jiří, Chrtek Jr., Jindřich, Chytrý, Milan, Jarošík, Vojtěch, Kaplan, Zdeněk, Krahulec, František, Moravcová, Lenka, and Pergl, Jan
- Type:
- article, model:article, and TEXT
- Subject:
- abundance, alien flora, checklist, casual, cover in plant communities, Czech Republic, exotic species, geographic origin, habitat niche, hybridization, impact, introduction-naturalization-invasion continuum, ivasive plants, life history, naturalized, non-native species, residence time, and taxonomy
- Language:
- English
- Description:
- A complete list of all alien taxa ever recorded in the flora of the Czech Republic is presented as an update of the original checklist published in 2002. New data accumulated in the last decade are incorporated and the listing and status of some taxa are reassessed based on improved knowledge. Alien flora of the Czech Republic consists of 1454 taxa listed with information on their taxonomic position, life history, geographic origin (or mode of origin, distinguishing anecophyte and hybrid), invasive status (casual; naturalized but not invasive; invasive), residence time status (archaeophyte vs neophyte), mode of introduction into the country (accidental, deliberate), and date of the first record. Additional information on species performance that was not part of the previous catalogue, i.e. on the width of species’ habitat niches, their dominance in invaded communities, and impact, is provided. The Czech alien flora consists of 350 (24.1%) archaeophytes and 1104 (75.9%) neophytes. The increase in the total number of taxa compared to the previous catalogue (1378) is due to addition of 151 taxa and removal of 75 (39 archaeophytes and 36 neophytes), important part of the latter being the reclassification of 41 taxa as native, mostly based on archaeobotanical evidence. The additions represent taxa newly recorded since 2002 and reported in the national literature; taxa resulting from investigation of sources omitted while preparing the previous catalogue; redetermination of previously reported taxa; reassessment of some taxa traditionally considered native for which the evidence suggests the opposite; and inclusion of intraspecific taxa previously not recognized in the flora. There are 44 taxa on the list that are reported in the present study for the first time as aliens introduced to the Czech Republic or escaped from cultivation: Abies concolor, A. grandis, A. nordmanniana, Avena sterilis subsp. ludoviciana, A. ×vilis, Berberis julianae, B. thunbergii, Bidens ferulifolius, Buddleja alternifolia, Buglossoides incrassata subsp. splitgerberi, Buxus sempervirens, Corispermum declinatum, Cotoneaster dielsianus, C. divaricatus, Euphorbia myrsinites, Gleditsia triacanthos, Helleborus orientalis, Hieracium heldreichii, Koelreuteria paniculata, Lonicera periclymenum, Lotus ornithopodioides, Malus baccata, M. pumila, Miscanthus sacchariflorus, Morus alba, Muscari armeniacum, Paeonia lactiflora, Pennisetum alopecuroides, Pinguicula crystallina subsp. hirtiflora, P. grandiflora subsp. rosea, Podophyllum hexandrum, Pyracantha coccinea, Rhodotypos scandens, Rumex patientia × R. tianschanicus ‘Uteuša’, Salix cordata, Sarracenia purpurea, Sasa palmata ‘Nebulosa’, Scolymus maculatus, Spiraea japonica, Tagetes tenuifolia, Thuja occidentalis, Trifolium badium, Vaccinium corymbosum and Viburnum rhytidophyllum. All added and deleted taxa are commented on. Of the total number of taxa, 985 are classified as casuals, 408 as naturalized but not invasive, and 61 as invasive. The reduction in the number of invasive taxa compared to the previous catalogue is due to a more conservative approach adopted here; only taxa that currently spread are considered invasive. Casual taxa are strongly overrepresented among neophytes compared to archaeophytes (76.7% vs 39.4%), while naturalized but non-invasive taxa follow the reversed pattern (18.8% vs 57.4). However, these two groups do not significantly differ in the proportion of invasive taxa. Of introduced neophytes, 250 taxa (22.6%) are considered vanished, i.e. no longer present in the flora, while 23.3% became naturalized, and 4.5% invasive. In addition to the traditional classification based on introduction–naturalization–invasion continuum, taxa were classified into 18 population groups based on their long-term trends in metapopulation dynamics in the country, current state of their populations, and link to the propagule pressure from cultivation. Mapping these population groups onto the unified framework for biological invasions introduced by Blackburn et al. in 2011 made it possible to quantify invasion failures, and boom-and-busts, in the Czech alien flora. Depending on inclusion criteria (whether or not extinct/vanished taxa and hybrids are considered), alien taxa ever recorded in the Czech Republic contribute 29.7–33.1% to the total country’s plant diversity; taking into account only naturalized taxa, a permanent element of the country’s flora, the figure is 14.4–17.5%. Analysis of the dates of the first record, known for 771 neophytes, indicates that alien taxa in the flora have been increasing at a steady pace without any distinct deceleration trend; by extrapolating this data to all 1104 neophytes recorded it is predicted that the projected number would reach 1264 in 2050. Deliberate introduction was involved in 747 cases (51.4%), the remaining 48.6% of taxa are assumed to have arrived by unintentional pathways. Archaeophytes are more abundant in landscapes, occupy on average a wider range of habitat types than neophytes, but reach a lower cover in plant communities. The alien flora is further analysed with respect to representation of genera and families, origin and life history. and Nevejdou se dvě poslední jména autorů
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Comparison of natural and artificial hybridization in Potamogeton
- Creator:
- Kaplan, Zdeněk and Fehrer, Judith
- Type:
- article and TEXT
- Subject:
- clonality, cpDNA, hybridization, internal transcribed spacer, plant taxonomy, Potamogeton, recurrent origin, sterility, and variation
- Language:
- English
- Description:
- The first attempt to artificially hybridize species of Potamogeton resulted in the hybrid P. perfoliatus × P. gramineus. The morphological features, reproductive behaviour and molecular markers of the offspring of this experimental hybridization were compared with those of the parental species and natural hybrids of the same assumed parentage. A phenotype corresponding to that of the natural hybrid P. × nitens was acquired from an experimental cross between P. perfoliatus and P. gramineus. All plants, both natural and artificial, of this hybrid were consistently sterile. They showed the ITS variants of both parental taxa, which is consistent with biparental inheritance of nuclear DNA. The experimental hybrid was used to test the maternal inheritance of chloroplast DNA in Potamogeton. Sequences of a chloroplast intergenic spacer (rpl20- rps12) were identical with those of the female parent. Then, the directions of the crosses resulting in the natural hybrids were investigated. Of five natural populations of P. × nitens, P. gramineus was the maternal parent of two and P. perfoliatus of three populations. The frequency of hybridization events and rise of hybrids are discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
4. first European record of Potamoge ×xubobtusus identified using ITS and cpDNA sequence data
- Creator:
- Zalewska-Gałosz, Joanna, Ronikier, Michał, and Kaplan, Zdeněk
- Type:
- article and TEXT
- Subject:
- hybridization, matroclinal variation, molecular identification, nomenclature, sequencing, taxonomy, and typification
- Language:
- English
- Description:
- A combined study of morphology, stem anatomy and DNA sequencing data (nuclear ribosomal ITS region and rpl32-trnL and rps12-rpl20 intergenic spacers of chloroplast DNA) was used to identify a putative Potamogeton hybrid from a river in NE Poland. Based on the morphological and anatomical characters the plants were tentatively identified as P. ×subobtusus Hagstr., a hybrid between P. alpinus Balb. and P. nodosus Poir. This identification was independently confirmed by the presence in hybrid individuals of an additive ITS sequence pattern from these two parental species. In all plants peaks corresponding to nucleotide states of both parents were clearly distinguishable, however the variants from P. nodosus dominated over those from P. alpinus. P. nodosus was also identified as the maternal parent of the hybrid based on cpDNA data and dominated the expression of morphological features in hybrid individuals. A detailed morphological description of P. × subobtusus and the typification of the name are provided. As P. nodosus rarely hybridizes with other species, existence of other hybrids, as well as possible difficulties in recognizing these taxa are also discussed.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
5. Hybridization of Potamogeton species in the Czech Republic: diversity, distribution, temporal trends and habitat preferences
- Creator:
- Kaplan, Zdeněk
- Type:
- article and TEXT
- Subject:
- Potamogeton, hybridization, taxonomy, revision, distribution, herbarium, morphology, nomenclature, typification, temporal changes, and new records
- Language:
- English
- Description:
- A revision of the diversity and distribution of Potamogeton hybrids in the Czech Republic is presented. Thorough examination of herbarium material and recent extensive field studies revealed the present and/or past occurrence of eight Potamogeton hybrids in the Czech Republic. In addition tomorphological characters, stem anatomy and/or molecular analysis were used to identify some of the hybrids. All the hybrids detected are between broad-leaved species of the genus, suggesting that hybrids between linear-leaved species may be overlooked because of the overall morphological similarity of taxa within this group. Four of the hybrids identified, P. ×nitens, P. ×olivaceus, P. ×sparganiifolius and P. ×undulatus, are recorded for the first time from the Czech Republic. Four of the hybrids are now extinct in the Czech Republic and the extant hybrids are rare. The occurrence of P. ×lintonii was not confirmed; the previous record was based on extreme forms of P. gramineus. The name P. ×concinnitus, proposed for a putative hybrid combination “P. pusillus × P. crispus”, was lectotypified and reduced to a synonym of P. crispus. Although the absolute number of finds of specimens of Potamogeton hybrids per decade is increasing, this is not a result of more frequent hybridization but of an increase in recording activity. Most records for recent decades are associated with targeted research by a few experts. The typical habitat of Potamogeton hybrids in the Czech Republic are ponds that were previously drained in summer and allowed to dry out. Many historical localities disappeared when the traditional fishpond management was largely abandoned and fish farming become more intensive. In the 19th century in particular some hybrids were recorded also in rivers but these occurrences generally disappeared after the extensive channelling of rivers at the beginning of the 20th century. Many hybrids occur at the same localities as their parents but it is documented that hybrids can persist vegetatively in the absence of the parental species, presumably as relics of the previous presence of the parent plants. Although almost all Potamogeton hybrids are consistently sterile, a cultivation experiment showed that P. ×angustifolius set seeds that were fertile and successfully produced adult plants.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
6. orphaned clone of Potamogeton ×schreberi in the Czech Republic
- Creator:
- Kaplan, Zdeněk and Fehrer, Judith
- Type:
- article and TEXT
- Subject:
- Potamogeton, hybridization, taxonomy, morphology, vegetative propagation, relic occurrence, distribution, new records, and rare taxon
- Language:
- English
- Description:
- A Potamogeton hybrid found growing in the absence of parental species in a South Bohemian stream, Czech Republic, was subjected to molecular analyses to identify its exact identity. RFLP of the ITS region confirmed its previous morphological identification as P. natans × P. nodosus (= P. ×schreberi). A comparison of its RFLP pattern with those of P. gramineus, P. lucens and P. polygonifolius unambiguously excluded the possibility that the investigated plants are specimens of other similar hybrids (P. ×fluitans, P. ×sparganiifolius, P. ×gessnacensis). The discovery of P. ×schreberi in South Bohemia is the first record of this hybrid for the Czech Republic. So far, it is known only from five countries and the Czech clone is one of a few extant clones of this hybrid in Central Europe. Chloroplast DNA sequencing identified P. nodosus as the maternal parent although at present this species neither occurs at the locality, nor upstream, nor in the entire drainage basin. The other species, P. natans, only occurs downstream of the locality in isolated side pools in a former stream bed and fishponds in an adjacent drainage basin. The available data indicate that this hybrid has persisted vegetatively at this locality for some time in the absence of its parents.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
7. Potamogeton schweinfurthii A. Benn., a new species for Europe
- Creator:
- Kaplan, Zdeněk
- Type:
- article and TEXT
- Subject:
- aquatic plants, distribution range, first record, herbarium, Mediterranean region, phytogeography, Potamogetonaceae, and taxonomy
- Language:
- English
- Description:
- The occurrence in the Mediterranean part of Europe of the African species Potamogeton schweinfurthii is recorded for the first time. So far, this native but overlooked species has been found on five major Mediterranean islands: Corsica, Sardinia, Malta, Kefallinía (Ionian Islands, Greece) and Crete. The species is most similar and presumably closely related to the mainly Eurasian P. lucens, with which it has been partly confused. The nomenclature and a description of P. schweinfurthii are provided, and its taxonomy and how it differs from similar taxa discussed. All known localities are listed, together with voucher specimens preserved in the major European herbaria. A distribution map of P. schweinfurthii in the Mediterranean region is presented.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
8. Potamogeton ×fluitans (P. natans × P. lucens) in the Czech Republic
- Creator:
- Kaplan, Zdeněk, Plačková, Ivana, and Štěpánek, Jan
- Type:
- article and TEXT
- Subject:
- Potamogeton, hybridization, isozymes, electrophoresis, and enzyme activity
- Language:
- English
- Description:
- Evidence from isozyme electrophoresis confirmed previous hypothesis on the occurrence of interspecific hybridization between Potamogeton natans L. and P. lucens L. formulated on the basis of morphology and stem anatomy. Isozyme phenotypes of the morphologically intermediate plants were compared with those obtained from the putative parents growing in the same locality. P. natans and P. lucens differed consistently in at least 12 loci and possessed different alleles at 7 loci. The hybrid had no unique alleles and exhibited an additive “hybrid” isozyme pattern for all 7 loci that could be reliably analysed and where the parents displayed different enzyme patterns. Both true parental genotypes were detected among samples of plants of P. lucens and P. natans from the same locality. The hybrid plants represent a recent F1 hybrid generation resulting from a single hybridization event. Consistent differences in enzyme activity between submerged and floating leaves of P. natans and P. ×fluitans were observed in all interpretable enzyme systems.
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/
9. Rizika spojená s vysazováním nepůvodních druhů rostlin do přírody a posilováním populací ohrožených druhů
- Creator:
- Kaplan, Zdeněk, Brabec, Jiří, Hadinec, Jiří, Hroudová, Zdeňka, Chrtek jun., Jindřich, Soldán, Zdeněk, and Šída, Ota
- Type:
- article and TEXT
- Language:
- Czech
- Description:
- Kulér / Forum
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/
10. Rizika spojená s vysazováním rostlin do přírody: Cesta do pekel dlážděná dobrými úmysly
- Creator:
- Kaplan, Zdeněk
- Type:
- article, model:article, and TEXT
- Language:
- Czech
- Rights:
- http://creativecommons.org/publicdomain/mark/1.0/ and policy:public