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Ecological consequences of polyploidization in populations of the wetland plant Butomus umbellatus
Rydlo, Jan ; Fér, Tomáš (advisor) ; Trávníček, Pavel (referee)
This thesis aimed on comparison of environmental requirements and morphological and biological traits of diploid and triploid cytotypes of wetland plant flowering rush (Butomus umbellatus), occurring in Eastern Slovak Lowland in unique mixed populations, and to develop primers for variable microsatellite loci suitable for further genetic studies. In total, 72 populations of Butomus umbellatus were found. The analysis of relative genome size by the flow cytometry (FCM) technique revealed 34 exclusively triploid cytotype populations, 8 exclusively diploid populations and 30 mixed populations of Butomus umbellatus. In mixed populations, the numbers of diploid and triploid individuals are quite equivalent and the plants create combined compact communities. Analyses of environmental characteristics of sites with specific cytotypes (PCA, RDA, ANOVA) revealed no difference in site requirements of diploid and triploid Butomus umbellatus plants. Morphometric analyses (PCA, CDA) of traits of 36 diploid and 54 triploid plants confirmed differing morphology of both cytotypes occurring in the nature. Subsequent replanting of these plants into pots and cultivation further increased these differences. The ratio of width and length of internal perianthium is the most reliable parameter to distinguish diploid and...
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Variation of the species Urtica dioica in Central Europe
Rejlová, Ludmila ; Urfus, Tomáš (advisor) ; Mandák, Bohumil (referee)
Although the European flora belongs to the best explored at the global scale, still there are several largely neglected plant groups, which may surprise by marked variation. One of these groups is Urtica dioica s. l., consisting of vaguely described taxa (microspecies / subspecies) with indefinite distribution. The most important source of variation in U. dioica s. l. is probably polyploidy (2x, 4x; x = 13). The complex comprises an ubiquitous tetraploid cytotype (U. dioica s. str.) and several obscurely defined relict 2x taxa. The cytogeographical analysis through Europe (770 populations / over 3 200 individuals) revealed marked distribution pattern of U. dioica s. l. cytotypes. We identified 106 diploid populations (13%) and 633 (82%) tetraploid populations. For the first time we detected triploid and pentaploid level (from mixed populations). Prevailing tetraploid U. dioica s. str. is predominantly synanthropic, whereas diploid taxa strictly occur in primary and relict habitats (primarily alluvial forests, tundra, Mediterranean mountains). The analysis of the absolute genome size of individuals from U. dioica clade and other closely related taxa showed different values of 2x U. kioviensis (19 % higher than 2x U. d. subsp. subinermis) and 2x U. bianorii (33% higher than 2x U. d. subsp....
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Dental phenotype variation in voles during the present glacial cycle
Putalová, Tereza ; Horáček, Ivan (advisor) ; Kuneš, Petr (referee)
The phenotype dynamics of arvicolid rodents during the terminal stages of the Vistualian glacial and the earliest Holocene was investigated with aid of a detailed morphometric analyses of extensive dental material from three sedimentary series of that age. The particular attention was paid to the record from a section in Býčí skála cave, Moravian karst, which demonstrated details of the Pleistocene/Holocene transition (12.4-8.4 ky BP) with extraordinary resolution. It revealed that dramatic rearrangements in community structure were accompanied by significant rearrangements of the phenotype dynamics in all arvicolid species. Despite some trends specific for particular species, some common features were identified as well. One of them was a rapid turnover in phenotype structure by the end of Younger Dryas, at time of the Preboreal event. (11.7-11 ky BP), the other was associated with the extensive shifts in community structure and habitat diversity at terminal stage of the Preboreal (9.7-9.3 ky). The core arvicolid species of Preboreal communities, Clethrionomys glareolus, Microtus arvalis, M.agrestis and Arvicola terrestris, exhibited repeated fluctuations during that stage (ll-9,3 ky BP) both in abundance and phenotype characteristics, supposedly related to serial invasion events during that time....
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Evolution of birches from Betula pendula and B. pubescens group: morphological and molecular reappraisal
Kaněra, Lukáš ; Fér, Tomáš (advisor) ; Urfus, Tomáš (referee)
The genus birch (Betula) consists of woods that grow nearly on the whole northern hemisphere. They have been intensively studied since the 2. half of the 19. century which led to the description of tens of species. During time the genus has been divided into several sections, which changed in the opinions of different authors. The study of their evolution and diversity is difficult due to frequent interspecific hybridisation and polyploidisation. Understanding this issue is also complicated due to a large number of morphologically similar defined species. Different methods have been used to study birch evolution, from morphometrics to the present time study of the genome. The objective of this text is to summarize the knowledge and to enable the reader easy access to it. Key words: Betula, birch evolution, hybridization, morphometrics, flow cytometry, DNA analysis, birch taxonomy
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Phylogenetic, morphological and ecological context of microevolution in pennate diatoms
Veselá, Jana ; Neustupa, Jiří (advisor) ; Řeháková, Klára (referee) ; Vanormelingen, Pieter (referee)
Visual assessment of discontinuities in the morphological features of diatom cells has been widely used in the discovery and delimitation of diatom species. However, a multidisciplinary approach to species-level taxonomy has revealed hidden diversity within the traditional diatom morphospecies. Consequently, this work examined both the natural and clonal populations of diatoms by diverse traditional and modern approaches, in order to assess the diversity, ecology, and distribution of diatom species. Although a detailed investigation of natural diatom samples was confounded by uncertain morphological boundaries between the traditional diatom species, it recognized that the diversity was relatively high; even one new diatom species was described using the morphological species concept. The multivariate statistical analyses showed that the variation of natural communities of traditional diatom morphospecies reflected differences in the local environmental conditions, as well as microhabitat heterogenity within a region. Since each diatom morphospecies is most likely a complex of sibling species, the two model traditional morphospecies were investigated, in order to assess morphological variation, genetic diversity, and/or the reproductive compatibility of monoclonal cultures. Even though isolated...
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Hybridization and microevolutionary relationships among Central European Diphasiastrum species
Dvořáková, Kristýna ; Urfus, Tomáš (advisor) ; Chrtek, Jindřich (referee)
Genus Diphasiastrum Holub is one of the most complicated and biosystematically very little investigated groups within Lycopodiaceae family. There are 6 species recognized in Central European region. Three of them (D. alpinum, D. complanatum, D. tristachyum) are considered basic - parental taxa, and their hybridization probably gave origin to the three adjacent species - intermediates (D. issleri, D. zeilleri, D. oellgaardii). These supposedly hybridogenous taxa often co-ocur with at least one parental species. All the taxa often meet in secondary habitats where they tend to form hybrid swarms (e.g. on ski slopes which represent an ideal biocorridor for meeting the species from alpine zone with the species from lower altitudes). In such places reciprocal crossings between all of the taxa occur, often accompanied by introgression. The degree of hybridization, including the possible introgression, was studied using absolute genome size analyses combined with classical and geometric multivariate morphometrics. Genome size was estimated for 570 plants from 83 localities, mostly from the Czech Republic. Despite the fact that each parental taxa had a specific range of absolute genome sizes, adjacent species formed more or less disconnected continuum. Multivariate statistical methods (PCA, RDA, Loess, PLS)...
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An assessment of interspecific hybridization between Central-European taxa from the genus Nymphaea: insights from flow cytometry and multivariate morphometrics
Kabátová, Klára ; Suda, Jan (advisor) ; Rybka, Vlastimil (referee)
Although the genus Nymphaea (waterlily) includes only two native species (N. alba and N. candida) in Central Europe, it poses a great challenge to taxonomy and biosystematics. The determination of both species is hampered by their phenotypic similarities, and species boundaries can be further blurred by interspecific hybridization. In addition, ornamental cultivars of different parentage often escape from cultivation and make the situation even more complex. To get insight into the caryological and phenotypic variability of czech waterlilies, the DNA flow cytometry and both distance-based and geometric morphometrics were used. Collections showed two different groups of fluorescence intensities, corresponding to N. alba and N. candida, respectively. In addition, intermediate values of nuclear DNA amount were found in some plants from South Bohemia, indicating their hybrid origin. Surprisingly, ornamental cultivars possessed the smallest genome sizes. The amount of nuclear DNA therefore seems to be a promising species-specific marker that enables not only native species but also cultivars to be distinguished. Cytometrically-proven individuals have been subjected to multivariate morphometrics, and high differenciation was discovered especially between native species. More complicated seems the distinction...
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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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Biosystematic revision of the Spergularia echinosperma complex
KÚR, Pavel
This thesis is focused on the biosystematic study of the Central-European endemic Spergularia echinosperma. With the combined use of morphometric analyses, genome size measurements and molecular tools, the taxonomic issues associated with this species have been clarified. The existence of S. kurkae, a stable allotetraploid hybrid between diploid S. echinosperma and tetraploid S. rubra, has been proven. Based on several lines of evidence, including distinct morphological separation and frequent occurrence in the absence of the parental species, treating S. kurkae as a separate species is proposed. In addition, two infraspecific taxa within S. echinospermaS. echinosperma subsp. echinosperma and S. echinosperma subsp. albensisdiffering in distributions and ecology have been described. A complete revision of the localities of S. echinosperma, S. kurkae and S. rubra in the Czech Republic is also presented. Furthermore, the development of 16 polymorphic microsatellite loci for S. echinosperma is reported.
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Morphometric analyse of Vinca minor populations in the CZU university collection
Závorková, Hana ; Karlík, Petr (advisor) ; Černý, Tomáš (referee)
Lesser periwinkle (Vinca minor) is pretty common, perennial and woody plant, for centuries disseminated for her aesthetic and medicinal use. The aim of this thesis is to try to identify, if individual subjects disseminated throughout the Czech Republic may come from one or more sources or clones. It was collected a total of 135 individuals throughout the Czech Republic, and these individuals were grown for several years in uniform climatic conditions in campus of the Czech Agricultural University in Prague. For these plants were then performed a morphological measurements and statistical evaluation was performed by programs Statistica12 and Canoco5. From data obtained this way was revealed that the morphological features of individual plants are dependent on the type of site, and therefore it is clear that individuals grown on historically verifiable sites probably originate from one or several clones. Another aim of this work is to determine whether the periwinkle occurring in the Czech Republic differ in their morphological and physiological characteristics such as stem length, length and width of leaf, petiole length, number of nodes on the flowering stem and the ratio length / width of the leaf. The results implies the fact that individuals differ in morphological features depending on the location of their occurrence, such as parks, churches, cemeteries and forests. The results further shows to us that location no. 2 differs significantly from the other locations in the length of the stem, leaf length, number of nodes and in the ratio length / width of the leaf. This is confirmed by the results of the program as Statistica12 and the results of the program Canoco5.
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