Chromosome numbers in selected species ofHieracium sect.Alpina (Asteraceae) from Central and eastern Europe

Chromosome numbers are reported for 15 taxa ofHieracium sect.Alpina (Griseb.)Gremli from Central and eastern Europe (Austria, the Czech Republic, Poland, Romania, Slovakia, Ukraine). The mode of reproduction was also studied for some of the taxa. For the first time the chromosome counts of 5 taxa from theHieracium rohacsense group are given:H. rohacsense Kit. (the West Carpathians),H. ratezaticum (Nyár. etZahn)Mráz (the South Carpathians) and a still unnamed taxon of theH. rohacsense group from Mt. Pop Ivan (the East Carpathians) are tetraploid (2n=36);H. rauzense Murr (the Eastern Alps) andH. borsanum Mráz (the East Carpathians) are triploid (2n=27).H. krivanense (Woł. etZahn)Schljakov (the West Carpathians) is tetraploid,H. brevipiliferum Mráz (the South Carpathians) is triploid; these are the first karyological reports of both taxa belonging to theH. fritzei group. The tetraploid chromosome number was revealed for the first time in an unnamed taxon of theH. nigrescens group from the West Carpathians, and inH. nigrescens subsp.koprovanum Rech. f. etZahn. InH. alpinum L. s.str. triploid (2n=27) populations from the West Carpathians and diploid populations (2n=18) from the East Carpathians were confirmed. ForH. halleri Vill. (theH. alpinum group, the West Carpathians) andH. nigrescens Willd. (the West Sudeten), the numbers 2n=27 and 2n=36, respectively were found, which is in accordance with previous data. The triploid level (2n=27) forH. pinetophilum (theH. fritzei group) and the tetraploid level (2n=36) forH. stygium Uechtr. (theH. chlorocephalum group) both from the West Carpathians were confirmed. One new species, onenomen novum and one new combination at the level of species are published in this paper.     

Hieracium × grofae — a rediscovered diploid hybrid from the Ukrainian Carpathians

Diploid hybrid plants (2n = 18) between sexual diploid cytotypes of Hieracium alpinum and H. umbellatum were found in the Ukrainian Eastern Carpathians. They were identified with H. × grofae Woł., originally used for the combination H. decipiens × H. umbellatum var. lactaris. As H. decipiens sensu Woł. (non Tausch) does not produce viable pollen grains and is most probably a polyploid apomict, it is unlikely to produce diploid hybrid plants with diploid H. umbellatum. Both parent species, Hieracium alpinum and H. umbellatum are also given by Wołoszczak from the original locality. Thus we conclude that H. × grofae is result of hybridization between H. alpinum and high mountain form of H. umbellatum. Hybrid plants are morphologically intermediate between the parent species, and moreover resemble closely or they are identical with the experimental hybrids of the same parent combination. Hybrids produce rather high amount of homogeneously sized pollen grains (values of standard deviation and coefficient of variation lower then upper limits for diploids — 3μm or 7.5%, respectively), and might probably serve as male parents in further crosses; on the other hand, they are fully seed-sterile. A lectotype of H. × grofae, a second proved nothotaxon in the genus Hieracium s.str., is designated. Localities of H. × grofae are located in subalpine belt of the Marmarosh Mts, the Svydovets’ Mts and the Horhany Mts (all in the Ukrainian Eastern Carpathians). Biotopes of hybrid plants usually represent secondary formed and disturbed pastures allowing close contact of altitudinally vicariant parent taxa.     

Interspecific hybridization in the genus Hieracium s. str.: evidence for bidirectional gene flow and spontaneous allopolyploidization

Although reticulation has indisputably played an important role in the evolutionary history of the genus Hieracium s. str. (Asteraceae), convincingly documented cases of recent interspecific hybridization are very rare. Here we report combined evidence on recent hybridization between two diploid species, Hieracium alpinum and H. transsilvanicum. The hybrid origin of the plants from the Romanian Eastern Carpathians was supported by additive patterns of nuclear ribosomal DNA polymorphism (ITS), an intermediate position of hybrid plants in principal coordinate analysis based on amplified fragment length polymorphism phenotypes (AFLP), and additivity at one allozyme locus. Flow cytometric analyses and chromosome counting showed that two hybrids were diploid (2n ~ 2x ~ 18) while one was surprisingly tetraploid (2n = 4x = 36). To our knowledge, this is the first record of spontaneous polyploidization following interspecific crossing in the genus. Allozyme data, especially the presence of unbalanced heterozygosity at one locus, suggest the origin of this tetraploid via a triploid bridge with subsequent backcrossing to H. alpinum. According to PCR-RFLP analyses of the trnT-trnL intergenic spacer, all H. ×krasani hybrids examined had the H. alpinum haplotype while H. transsilvanicum served as a pollen donor. The hybrids occurred at the locality with abundant H. alpinum plants where paternal H. transsilvanicum was missing. Previously reported instances of interspecific hybridization between the same parental taxa showed an opposite direction of crossing and relative abundance of parental taxa. This suggests that the direction of hybridization might be influenced by the frequency of parental taxa at the locality.     

Mentor effects in the genus<Emphasis Type="Italic">Hieracium</Emphasis> S.STR. (<Emphasis Type="Italic">Compositae,Lactuceae</Emphasis>)

Self-incompatibility was demonstrated in the diploid taxaHieracium alpinum andH. umbellatum using isolation experiments. However, self-incompatibility was broken down in diploidH. alpinum under the influence of foreign pollen from another species of this genus (mentor effects) during a series of crossing experiments. Interestingly, failure of the SI system was also recorded in diploidH. alpinum in an intergeneric cross with the representative of the closely related genus ofPilosella. This is the first record of autogamy in the genusHieracium s.str. The possible evolutionary significance of this phenomenon is discussed.     

Morphometric and RAPD study of theMelampyrum sylvaticum group in the Sudeten, the Alps and Carpathians

TheMelampyrum sylvaticum group is a heterogeneous group at the inter- and infra-specific level. A wide range of morphological characters was examined on specimens collected for this study. The corolla size, the corolla colour and the anther length are considered the most important morphological characters at the interspecific taxonomic level. The morphological and molecular variation of theMelampyrum sylvaticum group in the Sudeten, Alps and Carpathians was analyzed. The morphometric study of European populations ofMelampyrum sylvaticum group partly clarified the pattern of the variation of selected characters in this region. The RAPD analysis manifests a very similar trend of the population grouping. The combined analysis of morphological and molecular data gives the most explicit results. Central European yellow flowering populations ofM. sylvaticum group form two distinctive groups. The first one is an exclusive type of the Alps and of the Hercynian Mountains (except the Sudeten). The second group has its centre of distribution in the eastern part of the Carpathians. This type was described asMelampyrum herbichii from the present Ukrainian Carpathians and was regarded to be endemic to the Eastern and Southern Carpathians. Populations from the Western Carpathians and Sudeten Mts. are polymorphic. They seem to be closer toM. herbichii based on the RAPD markers, whereas the morphology of most populations from these regions is closer toM. sylvaticum s.str. The bract shape seems to be important for discrimination between both groups of populations along with the flower characters and a modest ecological differentiation. The Eastern CarpathianMelampyrum saxosum with white corolla is very close toM. herbichii based on the studied morphological characters.     

Rare recent natural hybridization in Hieracium s. str. – evidence from morphology, allozymes and chloroplast DNA

The first proven data on natural hybridization in the genus Hieracium s. str. are presented. Plants with intermediate morphological characters between the diploids H. alpinum and H. transsilvanicum were found in the Muntii Rodnei (Romanian Eastern Carpathians) in 2001 and in the Chornohora Mts (Ukrainian Eastern Carpathians) in 2003. While plants of intermediate morphology between usually so called basic species are usually tri- or tetraploid in Hieracium s. str., these plants were diploid (2n=18) like both parental species in this region. The Romanian plant did not produce fertile achenes in free pollination and in control backcrosses with H. transsilvanicum, two hybrids from Ukraine were completly seed sterile in free pollination and reciprocal crosses. Pollen stainability as an indirect measure of male fertility was quite high in the studied Ukrainian hybrid plants and similar to the parental taxa. Evidence from allozyme analysis also confirmed the hybrid origin of the studied plants. Sequencing and PCR-RFLP analyses of the trnT-trnL intergenic spacer revealed that all hybrid plants had the H. transsilvanicum chloroplast DNA haplotype. Maternal inheritance of chloroplast DNA in this particular cross was proved with artificial hybrids from reciprocal experimental crosses between H. alpinum and H. transsilvanicum. In both localities, the natural hybrid plants were found in disturbed habitats, exceptionally allowing contact of the otherwise ecologically vicariate parental species. Morphologically, the hybrid plants belong to H. × krasani Woł.     

Endemische Phytoassoziationen aus den Rumänischen Karpaten

The importance of endemic species for plant communities in the Roumanian Carpathians Mts. has been studied and discussed. Associations of the classAsplenietea trichomanis endemic in the South Carpathians were surveyed; they were classified into some endemic alliances (Gypsophilion petraeae, Micromerion pulegii, andSilenion lerchenfeldianae). Their locus classicus, nomenclatoric type and present distribution were also given.     

Salix silesiaca communities in the Fatra Mts. (Central Slovakia)

Two new associations belonging to theSalicion silesiacae within theBetulo carpaticae-Alnetea viridis are described. These are disclimax shrub communities dominated bySalix silesiaca at higher altitudes of the Fatra Mts. (Western Carpathians). Synmorphological, synecological, syntaxonomical, syngenetical and synchorological characteristics of the communities are given. Floristic differences between the montane shrub communities in the Western Carpathians and those in the Sudeten Mts. are summarized in a synthetic table.     

Cytotype distribution inEmpetrum (Ericaceae) at various spatial scales in the Czech Republic

Ploidy levels inEmpetrum (crowberry) from the Czech Republic and from one adjacent locality in Poland were estimated by flow cytometry to examine cytotype distribution patterns at large (within the country), medium (within mountain ranges) and small (within particular localities) spatial scales. Diploid, triploid, and tetraploid individuals were found. Triploids are reported from Central Europe for the first time; they occurred in the Krkono?e Mts. Exclusively diploid plants were observed in three mountain ranges (the Kru?né hory Mts., Labské pískovce Mts., Adr?pa?sko-Teplické skály Mts.), exclusively tetraploids were observed in the Jeseníky Mts., and both cytotypes were observed in the ?umava Mts., Jizerské hory Mts. and Krkono?e Mts. Except for the latter mountain range, diploids and tetraploids were always found in different habitats. Spatial isolation is supposed to be the main barrier preventing cytotype mating. A mosaic-like sympatric occurrence of different cytotypes was demonstrated in the Krkono?e Mts., where peat bogs and rocky places were not spatially separated. Eight of 11 localities studied there were inhabited by diploids and tetraploids (five localities), diploids and triploids (one locality) or all three ploidy levels (two localities). Diploid and triploid plants occasionally intermingled at 0.3 × 0.3 m. Flower sex in crowberries was strongly associated with ploidy level: diploids usually had unisexual flowers, the tetraploids bore exclusively bisexual flowers. However, a few diploid plants with hermaphrodite flowers occurred in one population in the Krkono?e Mts.     

Chromosome numbers in selectedHieracium species in the Krkonoše Mts. (the West Sudeten)

Chromosome numbers are given of 15 species of the genusHieracium L. s. str., representing seven species groups (in the sense of Flora Europaea, roughly corresponding to Zahn's “species principales”) from the Krkono?e Mts., N. Bohemia and SW Poland. For the first time chromosome numbers are reported forH. melanocephalum Tausch (2n=27),H. tubulosum Tausch (2n=36),H. schustleri Zlatník (2n=36),H. fritzei F. Schultz (2n=27),H. rohlenae Zlatník (2n=27),H. nigrescens Willd. (2n=36),H. decipiens Tausch (2n=36),H. atrellum Juxip inSchischkin etBobrov (2n=27),H. subnigrescens (Fries exNorrlin)Dahlst. (2n=36),H. sudeticum Sternberg (2n=36),H. pedunculare Tausch (2n=36),H. glandulosodentatum Uechtr. (2n=36),H. wimmeri Uechtr. (2n=27). InHieracium alpinum L. s. str. the number 2n=27 has been confirmed. The results show a high proportion of tetraploid taxa; no diploids have been found.     

Male meiosis,morphometric analysis and natural propagation in the 2× and 3× cytotypes of Tordyliopsis brunonis (Apiaceae) from northwest Himalayas (India)

Tordyliopsis brunonis (Apiaceae) is cytologically investigated here for the first time from India. The chromosome count of 2n = 33, ascertained here, represents a new intraspecific triploid cytotype in the species, supplementing the earlier report of a diploid cytotype with 2n = 22 from Nepal Himalayas. The diploid chromosome count (n = 11) has also been found in some of the presently investigated individuals which showed perfectly normal meiosis with 100 % pollen fertility and normal seed set. However, the individuals with triploid chromosome count showed irregular meiotic behaviour and abnormal microsporogenesis resulting in high pollen sterility (56.26 %) and no seed set. The irregular meiotic behaviour in the triploid individuals is attributed to the occurrence of variable number of univalents (1–7) at diakinesis and metaphase-I. In the subsequent meiotic stages, these univalents lagged at anaphases and constituted micronuclei in sporads. The triploid plants were also observed for natural propagation and it was noticed that no seeds were set. These plants were noticed to propagate vegetatively by rootstocks. Chromosomal pairing in triploid cytotype is typical of an allopolyploid. Based on the characterization of chromosomal pairing during meiosis, we assumed that the triploid individuals are probably alloploid in nature. Hypotheses concerning the possible origin of allotriploid in T. brunonis are also discussed.     

Distribution, chromosome numbers and nomenclature conspect of Arabidopsis halleri (Brassicaceae) in the Carpathians

Arabidopsis halleri represents an important model species for the study of phytoremediation. In the Carpathians it is represented by three subspecies: A. halleri subsp. halleri, A. halleri subsp. tatrica and A. halleri subsp. dacica. All three subspecies are diploid with chromosome number 2n = 16. They differ mainly in indument of flower parts, colour of petals and in the position of the longest leaf on stem. A. halleri subsp. halleri occurs in the Eastern and Southern Carpathians and in the northern and eastern part of the Western Carpathians, subsp. tatrica is endemic of the Western Carpathians and subsp. dacica occurs in the Eastern and Southern Carpathians most probably extending in its distribution further to the south to the Balkan mountains. Full synonymy of these three taxa and also a fourth European subspecies, A. halleri subsp. ovirensis is presented including the information on type specimens. Lectotypes are selected for several names. List of the examined herbarium specimens is given as well.     

<Emphasis Type="Italic">Hieracium</Emphasis> subgen. <Emphasis Type="Italic">Pilosella</Emphasis>: pollen stainability in sexual,apomictic and sterile plants

Two pollen stainability tests (Alexander’s stain and acetocarmine) were used to detect differences in pollen viability of the sexual, apomictic and sterile plants of Hieracium subgen. Pilosella. In sexual taxa (Hieracium bauhini and H. densiflorum), the average stainability was 93.7–98.4%. Similarly high stainability (92.2–97.2%) was found in the apomictic Hieracium pilosellinum and in the majority of the apomictic populations (or plants) of the pentaploid and hexaploid H. bauhini. In some apomictic plants of Hieracium bauhini the average pollen stainability was 49.0–75.4%. The lowest pollen stainability was found in the sterile plants, i.e. the triploid H. pistoriense (33.6%) and the pentaploid H. brachiatum (29.6%).     

Nardo-Agrostion communities in the Krkonoše and West Carpathians Mts.

The montaneNardus-rich acidophilous meadows occurring in the Krkono?e and W. Carpathians Mts. were evaluated. They are classified intoNardo-Agrostion tenuis Sillinger 1933. Five associations were distinguished:Sileno-Nardetum, Homogyno-Nardetum, Hieracio Lachenalii-Nardetum, Phleo alpini-Nardetum, andRanunculo nemorosi-Nardetum, the first occuring in the Krkono?e Mts., the others in the W. Carpathians.     

Hieracium vierhapperi (Asteraceae) a new species to the Carpathians, with some remarks on its origin

Hieracium vierhapperi (Zahn) Szeląg, known so far only from the Alps, was discovered in the Nízke Tatry Mts in Slovakia, as a new species to the Carpathians. Diagnostic characters, illustration and distribution as well as ecology of H. vierhapperi in the Nízke Tatry Mts are given. A key to distinguish H. vierhapperi from the morphologically related species is added. The Carpathian plants are tetraploid (2n = 36) and reproduce apomictically. The origin of H. sect. Cernua R. Uechtr in the Western Carpathians is briefly discussed.     

Iridoid glucosides of the genus Veronica s.l. and their systematic significance

 The mode of reproduction, pollen production, chromosome numbers, genetic variation (RAPD, allozymes) and overall similarity were studied in 6 species of Hieracium sect. Alpina in the Tatry Mts. (the Western Carpathians, Slovakia). All species were confirmed to be agamospermous and, except of H. krivanense and H. slovacum, lacking pollen grains. For the first time, a chromosome number is reported for H. krivanense (2n=4x=36). Considerable genetic variation was revealed in H. alpinum and a correlation between geographic and genetic distances was found in this species. Between-population variation in RAPD and allozyme phenotypes was found in H. pinetophilum and H. crassipedipilum. In all other species, allozyme and RAPD variation was low or absent. With few exceptions, the species differ in their allozyme as well as RAPD patterns. The relatedness of one population of endemic H. slovacum and H. halleri was confirmed. It is shown, that Carpathian species of the H. fritzei group are derived from at least two ancestors. Received July 3, 2000; accepted June 24, 2002 Published online: November 20, 2002 Addresses of the authors: H. Štorchová, (e-mail: storchova@ueb.cas.cz) Institute of Experimental Botany, Academy of Sciences of the Czech Republic, Rozvojová 135, CZ-165 00 Praha 6, Czech Republic. I. V. Bartish, J. Chrtek Jr., J. Kirschner, M. Tetera, J. Štěpánek, Institute of Botany, Academy of Sciences of the Czech Republic, CZ-252 43 Pruhonice, Czech Republic.     

Polyploidy and aneuploidy inOphrys,Orchis, andAnacamptis (Orchidaceae)

Studies on chromosome numbers and karyotypes in Orchid taxa from Apulia (Italy) revealed triploid complements inOphrys tenthredinifera andOrchis italica. InO. tenthredinifera there is no significant difference between the diploid and the triploid karyotypes. The tetraploid cytotype ofAnacamptis pyramidalis forms 36 bivalents during metaphase I in embryo sac mother cells. Aneuploidy was noticed inOphrys bertolonii ×O. tarentina with chromosome numbers n = 19 and 2n = 38. There were diploid (2n = 2x = 36), tetraploid (2n = 4x = 72), hexaploid (2n = 6x = 108) and octoploid (2n = 8x = 144) cells in the ovary wall of the diploid hybridOphrys apulica ×O. bombyliflora. Evolutionary trends inOphrys andOrchis chromosomes are discussed.     

Morphological and allozyme diversity in the Hieracium nigrescens group (Compositae) in the Sudety Mountains and the Western Carpathians

The overall pattern of morphological variation and genetic diversity (allozyme analysis) was studied in the Hieracium nigrescens group (H. nigrescens s.l., H. alpinum ≥ H. murorum) in the Sudety Mountains and the Western Carpathians. A morphological analysis was performed on 180 plants from 12 populations belonging to six a priori distinguished taxa. Altogether, 25 characters were measured or scored. Morphometric (canonical discriminant analysis) data separated five taxa, evaluated here at the species rank: H. chrysostyloides, H. decipiens, H. nigrescens (all from the Sudety Mountains), H. jarzabczynum, and H. vapenicanum (the Western Carpathians). A distinct local population from Mount Babia hora (the Western Carpathians) comprised a further possible taxon, given the preliminary name ‘H. babiagorense’. Genetic diversity was studied in 17 populations of H. chrysostyloides, H. decipiens, H. jarzabczynum, H. nigrescens, H. vapenicanum and ‘H. babiagorense’ using five enzyme systems. All a priori recognized species were proved to be genetically homogeneous, each consisting of one unique multilocus allozyme genotype, except ‘H. babiagorense’ which shared the same genotype with H. jarzabczynum. For the first time, a chromosome number is reported for H. vapenicanum (2n = 3x = 27) and previously published numbers were confirmed for H. chrysostyloides (2n = 5x = 45), H. decipiens (2n = 4x = 36), H. jarzabczynum (2n = 4x = 36), H. koprovanum (2n = 4x = 36), and H. nigrescens (2n = 4x = 36). All species have been shown to be endemic to either the Sudety Mountains or the Western Carpathians. Except for the species studied, two further ones (H. apiculatum, H. nivimontis) are recognized in the area, giving a total of seven species from the Hieracium nigrescens group in the area studied. The morphologically slightly different local population from Mount Babia hora/Babia Góra (‘H. babiagorense’) requires further study. Two new combinations are proposed: Hieracium jarzabczynum (Paw?. & Zahn) Mráz & Chrtek f. and Hieracium vapenicanum (Lengyel & Zahn) Chrtek f. & Mráz. © 2007 The Linnean Society of London, Botanical Journal of the Linnean Society, 2007, 153 , 287–300.