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Evolutionary history of tetraploid representatives Galium pusillum group (sect. Leptogalium) in central Europe. Allopatric differentiation of Czech endemic species G. sudeticum
Knotek, Adam ; Kolář, Filip (advisor) ; Chrtek, Jindřich (referee)
The presented study tries to reveal the evolutionary history of polyploid complex Galium pusillum aiming on a rare czech endemic species G. sudeticum, an ideal model to study allopatric speciation in the context of Central European (post)glacial development. The species G. sudeticum grows in Krkonose Mts. and on serpentines in western Bohemia (Slavkovský les) more than 200 kilometers away. Our morphological and molecular data suggest a clearly different history of its two isolated areas. The populations in Krkonose Mts. are probable relics of mountainous species G. anisophyllon which was there on its northern border of occurence and hybridized with lowland species G. valdepilosum during postglacial vegetations shifts. This fact is well supported by intermediate position of Krkonose Mts. populations in both morphological and molecular AFLP analyses and by sharing the same chloroplast haplotype with geographically close lowland populations. On the other hand the serpentine lowland populations in western Bohemia are both morphologicaly and genetically indistinguishable from G. valdepilosum. Distinct genetic lineage of few populations belonging to G. valdepilosum (incl. one traditionaly referred as G. sudeticum) was found in western Bohemia and Bavaria, located on relic stands (calcareous and serpentine...
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Genetic diversity and evolutionary history of Czech endemic taxa from the genus Dianthus
Kalůsková, Jana ; Suda, Jan (advisor) ; Chrtek, Jindřich (referee)
Abstract This MSc. thesis deals with karyological, genetic and phenotypic variation of selected taxa from the genus Dianthus L. in the Czech Republic and adjacent countries. The evolutionary history of the genus has been shaped by several microevolutionary processes, including interspecific hybridization, genome duplication, and edaphic speciation. These processes led to the origin of a number of phenotypically similar taxa, which are often restricted to a narrow geographic area. One subendemic and three endemic taxa occur in the Czech Republic. These (sub)species were used as model groups to gain insight into microevolutionary processes in small populations and the postglacial development of the genus in Central Europe. The thesis consists of three parts, each addressing different evolutionary phenomenon: Dianthus arenarius subsp. bohemicus is a critically endangered endemic psammophyte currently known from a single population in Central Bohemia. The site is also inhabited by widespread D. carthusianorum. Interspecific hybridization has been suspected on the basis of morphological characters, but this has never been confirmed by any other technique. I exploited differences in the number of chromosomes between both species and, with the aid of DAPI flow cytometry, estimated relative DNA contents of...
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Cardamine dentata, its distribution in Central Europe and relatinoship to C. pratensis
Holič, Filip ; Marhold, Karol (advisor) ; Chrtek, Jindřich (referee)
This thesis summarizes the documented information on the distribution of Cardamine dentata Schult. of the family Brassicaceae in the Czech Republic; it deals with the chromosome numbers and with ploidy levels of this species. Microsatellite markers were used to evaluate the potential relationships of C. dentata with other species of the group C. pratensis. Using a revision of available herbarium material it was found that the optimal conditions for the occurrence of C. dentata in the Czech Republic are in the phytogeographical regions of Thermophyticum and Mezophyticum at altitudes of 150-650 m a.s.l. No karyological data on this species were previously published from the area of the Czech Republic; using the flow cytometry and chromosomes counting it was revealed that in the area of the Czech Republic, populations with decaploid and undecaploid levels of ploidy occur. With help of microsatelite markers, it was confirmed that plants of C. dentata are genetically different from the other species of the C. pratensis group. Keywords: Cardamine, Cruciferae, microsatelite markers, chromosome numbers, geographical distribution, Czech Republic
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Local adaptation of natural population of Arabidopsis arenosa to serpentine soil
Lamotte, Timothée ; Kolář, Filip (advisor) ; Chrtek, Jindřich (referee)
Arabidopsis arenosa represents a promising model for studying the mechanisms underlying the adaptation to serpentine soil. Genetic basis of serpentine adaptation is still poorly known and A. arenosa possesses many advantages as a tool to complete that knowledge. The first step of this study was to reveal the presence of a local adaptation to serpentine soil in a population of A. arenosa. To do so, I used the data from a reciprocal transplant experiment realized between a Czech pair of serpentine - non-serpentine populations and I explored the phenotypes associated with the adaptation. Subsequently, I produced the F2 hybrids coming from crosses between serpentine - non-serpentine parents and I studied the expression of fitness traits in F2 plants growing in serpentine in order to estimate the number of loci underlying the adaptation which I compared with other studies. I confirmed the presence of a local adaptation, with the population of serpentine origin performing better than the non-serpentine population in the serpentine substrate of origin, associated with accumulation of heavy metals in the leaves. Analyses of the soil composition revealed differences in heavy metals and nutrients contents, Ca/Mg ratio and pH between the two localities. Those results fitted with the function of the candidate...
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Orchids as a model for research in ecophysiological adaptations of mycoheterotropic plants
Ponert, Jan ; Lipavská, Helena (advisor) ; Gryndler, Milan (referee) ; Chrtek, Jindřich (referee)
Perhaps all orchids are mycotrophic at early developmental stages, while majority of species photosynthesize at adulthood and only about 200 species remain fully mycotrophic for the whole life. Mycotrophy affects orchids at many levels. In this thesis, I focus on four aspects of orchid biology, which could be connected with mycotrophy: (i) systematics, (ii) genome size and endoreduplication, (iii) regulation of seed germination and (iv) mechanism of transfer of carbon and energy from fungi to orchids. There are over 27,000 recently recognized orchid species, nevertheless new ones are still discovering and old ones are revisiting. In this work I present a description of new species, Cleisostoma yersinii, and its morphological, anatomical, ecological and systematic characterization. Phylogeny reconstruction confirmed relationship with C. birmanicum. In the subtribe Podochileae, I reappraised the genus Campanulorchis to establish monophyletic but also morphologically defined group. For both abovementioned genera I prepared the artificial identification key. In the genus Dactylorhiza I revised taxa present in our country and I prepared an identification key which firstly mentions D. maculata subsp. elodes from Czech Republic. Orchid species diversity is probably reflected in genome structure. Results...
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Evaluation of cryptic diversity in the group of thread-leaved water-crowfoot (Ranunculus trichophyllus agg.)
Hanzlíčková, Johana ; Prančl, Jan (advisor) ; Chrtek, Jindřich (referee)
Ranunculus trichophyllus agg. (thread-leaved water crowfoot) represents a taxonomically challenging group of aquatic plants in which the presence of several significantly different genotypes and the genome size variation have been recently revealed. The results of previous studies suggest that cryptic taxa occur in this group, being so far overlooked due to considerable morphological reduction and extensivephenotypic plasticity. In this thesis, the variation and genetic relationships of four morphologically similar homophyllous water-crowfoot species was critically assessed in the area of Central Europe, using a combination of modern biosystematic methods (flow cytometry, direct DNA sequencing, morphometric analyses), specially focusing on the complex of R. trichophyllus.. The genome size analysis via flow cytometry was confirmed as a suitable method for determining the studied species; further, several hybrid combinations were revealed using this approach. However, recent interspecific hybridization is rather infrequent in the interest group. The results of DNA analyses indicate an importance of hybridization events in the evolution of sect. Batrachium: all the polyploid taxa studied are probably of allopolyploid origin. Two cryptic taxa within the traditionally recognized species R. trichophyllus have...
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The strength of minority cytotype disadvantage in plant populations consisting of diploid and polyploid individuals
Pilneyová, Markéta ; Čertner, Martin (advisor) ; Chrtek, Jindřich (referee)
Mixed-ploidy populations, consisting of multiple cytotypes, are an optimal system for studying genome doubling consequences in plants. The role of frequency dependent selection, known as minority cytotype exclusion principle, is very important in them, but there are many factors limiting this selection. In my thesis, I evaluate the changes in cytotype frequencies and pattern in permanent plots in natural mixed-ploidy populations of three plant species - Butomus umbellatus, Knautia serpentinicola and Tripleurospermum inodorum and I also experimentally analyze partial aspects of frequency dependent selection towards minority cytotype in artificially established mixed-ploidy arrays of two plant species - Arabidopsis arenosa and Tripleurospermum inodorum. Varied changes in frequencies of minority cytotype ware revealed in permanent plots. Usually there was decrease, but in two plots there was increase in minority cytotype frequency and in one case it became dominant. Observed changes depend on initial frequencies of minority cytotype in populations, biological properties of species and particular environment of permanent plot. Relative indexes describing the frequency and the strength of disturbances and also the amount of soil nutrients was used to compare the environment of permanent plots across...
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The cytotype diversity and population demography of invasive aster from Symphyotrichum lanceolatum a S. novi-belgii groups in Central Europe.
Varvažovská, Adéla ; Slovák, Marek (advisor) ; Chrtek, Jindřich (referee)
Asters from Symphyotrichum lanceolatum and S. novi-belgii a species complexes are native to North America from where they were imported to Europe as ornamental plants during the 19th century. They were naturalized and later became invasive in the humid habitats along rivers and lakes. Both species groups are karyologically and morphologically highly variable what is reflected in their complex taxonomy. A crucial role in the formation of their intricated diversity play inter- and intraspecies hybridization, polyploid evolution as well as phenotypic plasticity. The biological and ecological diversity of Asters was thoroughly studied in their natural environment in North America, however only little is known about their variability in their new, invaded European habitats. Numerous polyploid cytotypes were reported from their native distribution range in North America, however, only a single cytogeographic study in Europe has been published to date. The outcomes of this study accompanied by occasional chromosome counts indicated the existence of higher ploidy levels only. Specifically hexaploid and octoploid cytotype was reported for S. lanceolatus while hexaploids in S. novi-belgii. The problem of the karyological variability of these taxa in Europe deserves attention and further research. Key words:...
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Orchids as a model for research in ecophysiological adaptations of mycoheterotropic plants
Ponert, Jan ; Lipavská, Helena (advisor) ; Gryndler, Milan (referee) ; Chrtek, Jindřich (referee)
Perhaps all orchids are mycotrophic at early developmental stages, while majority of species photosynthesize at adulthood and only about 200 species remain fully mycotrophic for the whole life. Mycotrophy affects orchids at many levels. In this thesis, I focus on four aspects of orchid biology, which could be connected with mycotrophy: (i) systematics, (ii) genome size and endoreduplication, (iii) regulation of seed germination and (iv) mechanism of transfer of carbon and energy from fungi to orchids. There are over 27,000 recently recognized orchid species, nevertheless new ones are still discovering and old ones are revisiting. In this work I present a description of new species, Cleisostoma yersinii, and its morphological, anatomical, ecological and systematic characterization. Phylogeny reconstruction confirmed relationship with C. birmanicum. In the subtribe Podochileae, I reappraised the genus Campanulorchis to establish monophyletic but also morphologically defined group. For both abovementioned genera I prepared the artificial identification key. In the genus Dactylorhiza I revised taxa present in our country and I prepared an identification key which firstly mentions D. maculata subsp. elodes from Czech Republic. Orchid species diversity is probably reflected in genome structure. Results...
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