National Repository of Grey Literature 15 records found  1 - 10next  jump to record: Search took 0.01 seconds. 
Study of genetic diversity of Pectinatella magnifica (Leidy, 1851) colonies
MORAVCOVÁ, Vendula
Pectinatella magnifica is a freshwater organism from the bryozoan group, living in oligotrophic and mesotrophic waters where the temperature reaches 20°C during the year. It was first found and described by Joseph Leidy in the Philadelphia area in 1851. Although the original place of occurrence is North America, it is currently known as an invasive organism on other continents as well. Representatives of the species Pectinatella magnifica live in colonies with a characteristic spherical shape, which makes it easy to recognize and identify. These spherical colonies are covered with a community of zooids that produce a gel-like substance filling the colony itself. The reproduction of bryozoans is both sexual and asexual, with the non-sexual part exceeding the sexual part. The product of asexual reproduction are internal buds, so-called statoblasts, equipped with hooks, thanks to which they can attach to any substrate, which enables easy distribution even over long distances through otherwise difficult terrain. Although this is an ancient group with a predominance of asexual, therefore clonal, reproduction, the sexual part of reproduction enables the emergence of mutations and adaptation to new conditions. The dissertation is focused on determining the genetic diversity of colonies taken from the territory southern Bohemia and the surrounding area using molecular marker techniques. Two molecular techniques were used for processing genetic analyses, namely AFLP (Amplified Fragment Length Polymorphism) and ISSR (Inter Simple Sequence Repeat). Both techniques use universal primers to determine similarity between organisms.
Phylogeography of temperate plant species with the focus on Central Europe
Daneck, Hana
Phylogeography of temperate plant species with the focus on Central Europe Hana Daneck Charles University Prague Faculty of Science Department of Botany Supervisor: Prof. RNDr. Karol Marhold, CSc. Consultant: Mgr. Tomáš Fér, Ph.D. Praha 2012 Abstract This thesis presents contribution to clarification of postglacial history of temperate plant taxa in Europe with the focus on especially interesting region of Central Europe, for which diverse roles in postglacial plant histories were suggested. The first part of the thesis summarises general phylogeographical views and methodological approaches with the respect to species history after the last ice age in Europe. Further, the most important aspects of phylogeography of European temperate plant taxa are discussed. The second part contains a set of papers dealing with selected European temperate plant species, for which phylogeographical patterns throughout their present distribution area were inferred, including assumptions on the origin of their contemporary Central European populations and comparisons with another previously studied species.
Rezistence genes against fungi deseases in cereals and methods for their detection
Stuchlíková, Šárka ; Dumalasová, Veronika (advisor) ; Schwarzerová, Kateřina (referee)
The paper deals with the possibilities of detection fungal disease resistance genes in the original European cereals, such as wheat, barley, rye and oats. It provides an overview of the most important resistance genes for breeding. The significance of the resistance genes is evaluated on the basis of the harmfulness of the individual cereal fungal diseases, as well as the importance of the individual cereal species. It describes the possibilities of detecting resistance genes using molecular markers and compares various types of molecular markers. It seeks answers to the question of where the breeding on resistance and therefore the use of molecular markers brings the greatest benefit.
Population genetics of the fish tapeworm Wenyonia virilis (Caryophyllidea: Caryophyllaeidae) and its fish host Synodontis schall
JIRSOVÁ, Dagmar
The presented thesis consists of three papers/manuscripts (one published, one under review, one manuscript) on population genetic aspects of a host-parasite model, caryophyllidean tapeworm Wenyonia virilis and mochokid catfish Synodontis schall, in recently separated drainage basins, Lake Turkana and the Nile River. Three main topics are addressed herein: (i) intra- and inter-population genetic variability in and among hosts and parasites, (ii) comprehensive assessment of host model taxonomic status using multiple approaches, (iii) comparison of parasite intraspecific phenotypic with population genetic pattern. Two different genetic markers were applied to address these topics mtDNA (coxI) and whole genome scanning method (AFLP).
Phylogenetic Studies in the Polyploid Genus Curcuma L.
Záveská, Eliška ; Fér, Tomáš (advisor) ; Schmickl, Roswitha Elisabeth (referee) ; de Boer, Hugo (referee)
1 Phylogenetic Studies in the Polyploid Genus Curcuma L. SUMMARY Curcuma is genetically one of the most complex genera within the tropical family Zingiberaceae, with hybridization and polyploidization being the major forces in its evolution. In this thesis, I have focused mainly on the genetic background of Curcuma species variation, relationships and overall genome structure, as a key to solve long standing taxonomic problems. Results of my molecular studies on the genus Curcuma performed since 2007 represent an extension of ongoing taxonomic and nomenclatural work started by Jana Leong- Škorničková in 2000. The first part of the thesis consists of a broad, general introduction to the subject to reflect the current state of knowledge, formulate the major problems to be confronted within the genus, and summarise the major results of the studies presented in the second part of the thesis. As the main obstacles in studying Curcuma are consequences of its reticulate evolution, it is also outlines the importance of understanding the genetic background and species relationships using molecular markers. Common molecular methods used for assessing phylogenetic relationships on the intraspecific and infrageneric levels - AFLP and sequencing of selected markers from cpDNA, nrDNA and nDNA - are described, with the...
Ecological and evolutionary consequences of edaphic differentiation in plant polyploid systems
Kolář, Filip ; Suda, Jan (advisor) ; Tribsch, Andreas (referee) ; Krahulec, František (referee)
The thesis deals with evolutionary and ecological consequences of edaphic speciation (adaptation to different soil types) and genome duplication (polyploidization), acting in concert. Using a wide range of ecological, karyological and molecular approaches, several hypotheses of general importance have been examined in three model angiosperm systems (ploidy variable species or species aggregates occurring both on and off specific substrates, including serpentines and calcareous soils). In the Knautia arvensis group (Caprifoliaceae) a unique cryptic diploid lineage in central Europe was identified to be restricted to serpentine and limestone outcrops, which served as refugia during environmental changes (forest spread, human impact) in the Holocene. These refugial populations exhibited strong evolutionary potential because they were able to polyploidize and escape beyond the borders of their original edaphically-conditioned refugia owing to hybridization with surrounding widespread homoploid genotypes. Survival of both Knautia cytotypes on serpentine soils was facilitated by their high tolerance to chemical stress factors such as high Ni concentrations and low Ca/Mg ratios. In the Galium pusillum group (Rubiaceae), a striking cytological, ecological, and taxonomic, diversity was revealed in northern and...
Phylogeography of temperate plant species with the focus on Central Europe
Daneck, Hana
Phylogeography of temperate plant species with the focus on Central Europe Hana Daneck Charles University Prague Faculty of Science Department of Botany Supervisor: Prof. RNDr. Karol Marhold, CSc. Consultant: Mgr. Tomáš Fér, Ph.D. Praha 2012 Abstract This thesis presents contribution to clarification of postglacial history of temperate plant taxa in Europe with the focus on especially interesting region of Central Europe, for which diverse roles in postglacial plant histories were suggested. The first part of the thesis summarises general phylogeographical views and methodological approaches with the respect to species history after the last ice age in Europe. Further, the most important aspects of phylogeography of European temperate plant taxa are discussed. The second part contains a set of papers dealing with selected European temperate plant species, for which phylogeographical patterns throughout their present distribution area were inferred, including assumptions on the origin of their contemporary Central European populations and comparisons with another previously studied species.
Biology, ecology and invasion characteristics of Campylopus introflexus in the Czech Republic
Mikulášková, Eva ; Soldán, Zdeněk (advisor) ; Tribsch, Andreas (referee) ; Kučera, Jan (referee)
A B S T R A C T Ecological and economic impact of invasive plants to natural ecosystems is the subject of many studies; however, invasive bryophytes have been stud- ied only marginally. Campylopus introflexus (Hedw.) Brid. is one of the most strongly invasive bryophyte species in Europe. The species appears to be native in the Southern Hemisphere. In Europe, it was collected for the first time in the British Isles in 1941. The moss has expanded eastward and the first collection in the Czech Republic is dated to 1988. This thesis found that more than 70 localities were known known in the Czech Republic in 2006, and more than 100 localities became known by 2011. It has been further demonstrated that the Czech Republic was colonized repeatedly by generative spores and all populations have a unique genetic composition. Genetic variation of the populations is low, the genetic diver- sity of populations within the Czech Republic is not correlated with their geographic position or with any of the monitored environmental variables. At a fine scale within particular localities, the species disperses by vege- tative diaspores, while it uses generative spores for spreading over longer distances. In Central Europe, C. introflexus prefers open coniferous forests, especially plantations of either spruce or pine. It colonizes...
Phylogeography of temperate plant species with the focus on Central Europe
Daneck, Hana ; Marhold, Karol (advisor) ; Štech, Milan (referee) ; Tremetsberger, Karin (referee)
Phylogeography of temperate plant species with the focus on Central Europe Ph.D. Thesis Hana Daneck Charles University Prague Faculty of Science Department of Botany Supervisor: Prof. RNDr. Karol Marhold, CSc. Consultant: Mgr. Tomáš Fér, Ph.D. Praha 2012 2 Summary This thesis presents contribution to clarification of postglacial history of temperate plant taxa in Europe with the focus on especially interesting region of Central Europe, for which diverse roles in postglacial plant histories were suggested. The first part of the thesis summarises general phylogeographical views and methodological approaches with the respect to species history after the last ice age in Europe. Further, the most important aspects of phylogeography of European temperate plant taxa are discussed. The second part contains a set of papers dealing with selected European temperate plant species, for which phylogeographical patterns throughout their present distribution area were inferred, including assumptions on the origin of their contemporary Central European populations and comparisons with another previously studied species. Paper 1: Phylogeographic pattern of the European forest grass species Hordelymus europaeus: cpDNA evidence. This paper presents phylogeographical pattern based on chloroplast haplotype variation covering the...

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