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Infection pathway of Hymenoscyphus fraxineus and its interactions with ash mycobiota
Haňáčková, Zuzana ; Koukol, Ondřej (advisor) ; Adamčíková, Katarína (referee) ; Botella Sánchez, Leticia (referee)
Ash dieback is a disease that affected populations of native ash species throughout Europe at the beginning of the 21st century. It causes necrotic spots on the leaves, necrosis of shoots and branches and, especially in young individuals, the total death of the tree. In particular, F. excelsior is attacked by ash dieback. The causative agent of the disease is the invasive ascomycete fungus from Asia - Hymenoscyphus fraxineus. The aims of this dissertation thesis were as follows: 1) to study population structure of H. fraxineus at different scales - at regional scale (Czech populations) and at the level of particular ash petioles, this latter was to serve as a confirmation of the pathogen infection pathway; 2) to elucidate the effect of H. fraxineus on saprotrophs in the litter (namely H. albidus) and 3) to compare endophytic mycobiota of tolerant and susceptible F. excelsior trees and to test antagonistic interactions of these fungi against the pathogen. Analysis of Czech populations showed lower average gene diversity compared to other European populations with one Czech population differing significantly from the rest due to the lowest allelic richness and very low average gene diversity. The results indicate that despite minimal differences among European populations, local ecological or...
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Phylogeography and genetic diversity of the populations of Gobius niger (Gobiiformes: Gobiidae)
Hradečný, Jakub ; Vukićová, Jasna (advisor) ; Perdices, Anabel (referee)
Gobies (Gobiiformes: Gobiidae) are the most speciose fish family and the most abundant fish group of the European seas. Yet, the population genetic diversity has been studied in only a few European goby species. Although the ocean is seemingly a continuous habitat, there are barriers to gene flow in marine environment in form of e.g. straits or marine currents. The black goby (Gobius niger) is a demersal marine fish with planktonic larvae, inhabiting the coastal waters of Europe, north Africa and the Mediterranean and Black Sea coast of the Middle East. The current work examined individuals from 28 localities across the distribution range of the species in order to study the population genetic diversity. The analyses of two mitochondrial markers (cytochrome b and D loop) revealed a complex structuring of the population and a pronounced intraspecific diversity (maximum uncorrected p-distance 6.1 %). The population is divided into four very diverse haplotype groups, with unexpected geographic pattern. While the population inhabiting the Atlantic Ocean and the North Sea is generally genetically homogeneous, with all examined individuals bearing haplotypes belonging to a single haplotype group, the Mediterranean population is very complex, displaying a presence of four haplotype groups, some of which...
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Application of molecular methods in population genetic studies
Šurinová, Mária
A vast range of factors shape the genetic structure of plant populations. In this thesis, I focus on two of them. The first factor, polyploidization, is a process of chromosome set multiplication through whole-genome duplication within a single species (autopolyploids) or hybridization of two different species (allopolyploids). It rapidly brings changes into genomes, allowing species to occupy distinct niches, adapt to new habitats, colonize them, or adapt to changing environment in their native range. But it comes at a certain cost - difficulties in mitosis and meiosis, changes in cellular architecture. Furthermore, after cytotype establishment, new individuals have to deal with cytotype exclusion effect, competition with parental individuals and higher nutrition requirements. In this thesis, I present the effect of polyploidization on populations of three species- Arabidopsis arenosa, Aster amellus and Festuca rubra. The second factor changing the population genetic structure presented in this thesis is the fragmentation of populations. Population fragmentation can be caused by natural or anthropogenic activities and often leads to overall reduction in population size and reduced connectivity among fragments. Restricted gene flow may threaten long-term population survival due to inbreeding...
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Y chromosome in the mouse hybrid zone
Rubík, Pavel ; Munclinger, Pavel (advisor) ; Zemanová, Barbora (referee)
The contact zone between subspecies of house mouse Mus musculus musculus and Mus musculus domesticus is one of the most intensively studied hybrid zones. It is also due to extensive introgression of the Y chromosome of M. m. musculus subspecies to the genetic background of M. m. domesticus. One theory of the origin of the introgression explains it by intragenomic conflict between the sexes. With a set of variable microsatellite markers on the Y chromosome, I have examined the validity of this theory by simple approaches revealing the history of the introgression area. It turned out that overly big variability of our markers makes the revelation of this theory impossible. Our markers have been found suitable for use in the analysis of population structure of house mouse. Thanks to them, we can identify migrants between localities and estimate the level of closeness of the population structure in relation to migrants from the neighborhood. Populations in our analysis proved to be relatively closed and resistant to the influx of migrants. Despite the conclusions of previous research where the dispersion of males ran up to one kilometer, I have discovered a relatively large number of migrations to a distance of thirty kilometers. Keywords Mus musculus musculus, Mus musculus domesticus, Y chromosome,...
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Population structure of the gray wolf (Canis lupus)
Říhová, Jana ; Hulva, Pavel (advisor) ; Pivnička, Karel (referee)
Gray wolf (Canis lupus), is historicaly the most widespread carnivore with the former range including most of the northern hemisphere. The ambivalent relationship of humans to this predator resulted in extermination of this species in many areas, on the other hand led to the evolution of the dog, unique domesticant with vast phenotypic variation. The effort of conservation biology in last decades resulted in the shift of perception the role of big carnivores in ecosystems, with consequent recolonization of many regions by wolf, including the Czech republic. This changes brings the elevation of interest in this taxon by both experts and laymans. Present review aims to assemble published information regarding distribution, phylogeography, population structure, social and spatial behaviour of the gray wolf. The chapters describing the domestication process of the dog and hybridization with his wild ancestor are included.
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Internal structure of the Balkan refugium using Erinaceus roumanicus as a model organism
Eliášová, Kristýna ; Černá Bolfíková, Barbora (advisor) ; Zemanová, Barbora (referee)
The aim of this work was to describe the spatial distribution of genetic variability of the northern white-breasted hedgehog (E. roumanicus), mainly within the Balkan Peninsula and Central Europe, as these areas are crucial for understanding the effects of Pleistocene climate oscillations on the genetic architecture of the species. Based on this spatial distribution, hypotheses about the possible structuring of the Balkan refugia were formulated. A total of 260 individuals and 9 microsatellite loci were used for the analysis. Using the approach of landscape and population genetics several possible isolated subpopulations within the area surveyed were identified. Unique status was proved for a population originating from Crete, probably influenced by mechanisms of island evolution. Differences from the rest of the range were ascertained also in population from the Czech Republic, located in a secondary contact zone with the E. europeaus. The role of interspecific interactions and possible introgression should be considered in this case. In the area of Romania and the area south of the Balkan Peninsula the highest genetic distances between individuals were identified, probably associated with the occurrence of geographical barriers and the possible presence of glacial subrefugia. Other identified...
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Diversity, distribution and genetic structure of the tribe Pipistrellini
Eliášová, Kristýna ; Hulva, Pavel (advisor) ; Fornůsková, Alena (referee)
This literature review discusses phylogenetic relationships within the family Vespertilionidae with a detailed focus on tribus Pipistrellini relations and then the individual genera and species within this tribe. A historical summary of efforts to resolve the phylogenetic relationships within the taxon first on the basis of morphological studies, comparison of karyotype and most recently on the basis of genetic markers. Mitochondrial genetic markers are useful in studying phylogeography, as this paper shows on the example of the Pipistrellus species complex and on species Nyctalus azoreum, Nyctalus leisleri, Nyctalus noctula and Pipistrellus abramus. Furthermore, this work describes the current distribution of individual taxa of tribe, the fossil record and migration behavior of European temperate species in the context of their population structure (also studied in some species using mtDNA and microsatellites) and Annex shows the areas extending all five genera Pipistrellini tribe. Key words: Pipistrellini, phylogenenetics, phylogeography, distribution, population structure
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Application of molecular methods in population genetic studies
Šurinová, Mária ; Münzbergová, Zuzana (advisor) ; van Loo, Marcela (referee) ; Mandák, Bohumil (referee)
A vast range of factors shape the genetic structure of plant populations. In this thesis, I focus on two of them. The first factor, polyploidization, is a process of chromosome set multiplication through whole-genome duplication within a single species (autopolyploids) or hybridization of two different species (allopolyploids). It rapidly brings changes into genomes, allowing species to occupy distinct niches, adapt to new habitats, colonize them, or adapt to changing environment in their native range. But it comes at a certain cost - difficulties in mitosis and meiosis, changes in cellular architecture. Furthermore, after cytotype establishment, new individuals have to deal with cytotype exclusion effect, competition with parental individuals and higher nutrition requirements. In this thesis, I present the effect of polyploidization on populations of three species- Arabidopsis arenosa, Aster amellus and Festuca rubra. The second factor changing the population genetic structure presented in this thesis is the fragmentation of populations. Population fragmentation can be caused by natural or anthropogenic activities and often leads to overall reduction in population size and reduced connectivity among fragments. Restricted gene flow may threaten long-term population survival due to inbreeding...
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