National Repository of Grey Literature 19 records found  1 - 10next  jump to record: Search took 0.00 seconds. 
Ecology of the pathosystem Vinca minor - Puccinia cribrata in natural populations
Vaníček, Jiří ; Koubek, Tomáš (advisor) ; Macek, Martin (referee)
5 Absctract Environment and demographic characteristics of host population are important factors affecting incidence and severity of plant diseases. The aim of this study was to reveal possible effects of microclimatic and edaphic characteristics and host population demographic factors on the biotrophic pathogen Puccinia cribrata, microcyclic rust parasitising clonal evergreen plant Vinca minor. I studied the ecology of this pathosystem in natural populations of V. minor in the Soča valley in the Julian Alps in Slovenia. Rugged terrain of the Soča valley with different bedrocks allowed to study pathogen distribution at topographically diverse forest and scrub sites, greatly differing in soil depth and canopy structure. P. cribrata was significantly more likely to occur in the themophilous forest with shallow calcareous soils and open canopy than in the mesophilous forest types. Its prevalence (proportion of diseased stems in population) was also highest in this type of vegetation. Most important host population factors were population size and population density positively affecting incidence and prevalence respectively. Additionally, I tested various vegetation and topographic indexes derived from remote sensing for usability in prediction models. It appears that vegetation indexes connected with canopy...
Population models of plant life-cycles and their modifications by diseases and herbivores
Kasner, Marek ; Koubek, Tomáš (advisor) ; Koupilová, Klára (referee)
Pathogens and herbivores are two important groups of organisms with predominantly negative impact on their plant hosts. Although relationships at the individual level are relatively well understood, the data acquired by those studies cannot be easily translated into effects on the population. Various types of population models, also used in the case of the interactions, give us valuable insight into population dynamics. This bachelor thesis at first describes mechanisms and effects of plant pathogens (with emphasis on pathosystems with anther smut Microbotryum violaceum) and herbivores at the individual and population level for the demonstration of diversity of the systems and to stress the discrepancy between the two hierarchical levels. Furthermore, matrix and integral projection models are introduced as invaluable tools for population dynamics projections and understanding the underlying results of the interactions on plant populations. These models use the entire plant life cycle and require long-term censuses of demographic data. The role of these models in plant-pathogen interactions seems heavily underappreciated, however, and thus there is only a small number of studies with their application. The thesis describes mechanisms of the models, modifications in specific life-cycles and their...
Phenology of mangroves
Hradečný, Jakub ; Koubek, Tomáš (advisor) ; Sklenář, Petr (referee)
The mangroves are a globally important ecosystem with an important value for many organisms, humans included. Many of the organisms are addicted to leaf production, as a part of their diet. These foliovorous organisms are directly affected by mangrove phenology, which presents differences on the global scale. It seems possible that the phenology is influenced mainly by annual temperature oscillations and its changes mark the start and the end of phenological periods. The phenology of mangroves can be influenced by another climatic factor too, as for instance rainfall or salinity. In the latitudes of 20ř, the phenological phases show unimodal mode with the long duration of phenology periods, usually longer than one year. Closer to the equator, the phenology of the plants becomes to change into a bimodal mode, with more than one peak of phenological event per year. In the area of the equator, the phenology of the plants changes into a multimodal mode, without differences during the whole year. This ideal model can be changed by local climatic extremes changing the mangrove phenology into a different mode.
Influence of environment on distribution and coexistence of different diseases on a single plant species
Mráčková, Michaela ; Koubek, Tomáš (advisor) ; Koupilová, Klára (referee)
Most plant species host one or multiple pathogens. However, studies are mostly focused on simple pathosystems. These studies deal for example with the virulence of the pathogen, plant resistance or influence of the environment on the pathosystem. The occurrence of more pathogens in one plant species is taken into account only in a few studies. Most of those studies focus on the coinfection of multiple pathogens in one individual host, especially in the agriculture, so there is very little information about coexistence of more pathogens in wild plant population. This paper summarizes the general information about plant and pathogen interaction, focuses on environmental effects and finally focuses on occurrence of multiple pathogens on one plant species. From the studies it is clear, that both, abiotic (light, temperature, humidity, etc.) and biotic conditions (pollinators or pests as vectors etc.) have impact on host- pathogen interaction. During co-occurrence of multiple pathogens in one host plant, various interactions between coinfecting pathogens can occur (competition, cooperation, etc.). Resistance of plant to one pathogen can be affected by presence of other pathogens and stress factors. Finally, coinfection may also affect virulence of individual pathogens. Key words: plants, pathogens,...
Ecology of the pathosystem of anther smut on Dianthus carthusianorum
Koupilová, Klára ; Koubek, Tomáš (advisor) ; Dostál, Petr (referee)
Anther smuts (Microbotryum violaceum s.l.) represent a well-known system for studying pathogens of wild plants and coevolution between pathogens and hosts. Infected plants produce sterile flowers with anthers filled with fungal spores which are transmitted to other host plants by pollinators. Data from existing research come mainly from the genus Silene. However, the applicability of these findings to other host plants of anther smuts is largely unknown. Therefore, this thesis focuses on a different host species - Dianthus carthusianorum. First, the pattern of disease was surveyed in natural populations of D. carthusianorum in a small area in Střední Povltaví. Most populations were infected to various degrees and only a few populations remained completely healthy. The prevalence of disease was positively correlated with size and density of host populations. On the other hand, environmental factors and the degree of connectedness had very little effect on disease prevalence. Second, additional data were collected from a subset of populations to determine plant resistance and densities of pollinators. Differences in resistance among populations (as inferred from flower inoculations) were not significant. Populations differed in densities of pollinators, but there was no correlation between densities...
Effect of metapopulation structure and environmental factors on population biology of Impatiens noli-tangere infected by powdery mildew Podosphaera balsaminae
Chalupníková, Jana ; Koubek, Tomáš (advisor) ; Čuda, Jan (referee)
Studies performed on natural pathosystems revealed that the spatial structure of the metapopulation plays an important role in the development and spread of disease; phytopathological experimental studies have also revealed a significant effect of climatic factors on the presence of the disease (incidence) and the level of infection (prevalence) in populations. The aim of this study was to explore a natural pathosystem from both sides at the same time and to see which local and spatial environmental factors influence the development of pathosystem. Study focuses on population biology of natural pathosystem Podospaera balsaminae - Impatiens noli-tangere, which has not been investigated yet. In the study area (between the city Sázava (Benešov district) and village Vlkančice) host populations occurred in 78 (64 of them were infected) in 2013 and 82 populations (61 of them were infected) in 2014. Size of host populations had the strongest effect to incidence and prevalence of disease in the pathosystem. In larger populations, the disease occurred more often, developed faster and was higher. The rate of spread of the pathogen territory and the rate of population host connectivity had also strong effect. The abundance of pathogen in the studied area and the level of connectivity of host populations also...
Habitat dependence of persistence of clonal connection in plants
Martincová, Nina ; Weiser, Martin (advisor) ; Koubek, Tomáš (referee)
The review is about the role of environment to the longevity of connection in clonal plants. The first part is dealing with theoretical models, which describe the interaction of plants with different strategies in longevity of clonal connection in a model habitat. Subsequently, it analyses concrete attributes of the environment - heterogeneity, carrying capacity, amount of disturbances and competition. This part focuses more thoroughly on their impact on persistence of clonal connection and strategy of clonal reproduction in general. The last part refers to some other phenomena which could influence the length of persistence of a clonal connection.
Case Study of Physiotherapy Treatment of a Patient with the Diagnosis of Ischemic Stroke
Koubek, Tomáš ; Novotná, Irena (advisor) ; Křížková, Štěpánka (referee)
This bachelor thesis deals with ischemic stroke. It has two parts. General part consists of anatomy and physiology of brain vessels and risk factors of stroke. Continues with theory concerning ischemic stroke, its pathogenesis, pathophysiology, clinical symptoms, classification, diagnostics and treatment. Mentioned is also hemorrhagic stroke and subarachnoid hemorrhage . The end of this part contains neurorehabilitation. Special is aimed on a case study of a patient with diagnosis of ischemic stroke. Consists of complex kinesiology examination, process of therapy and overall evaluation. This part was based on clinical practice in Oblastní nemovnice Kladno, in term from 6.1. till 31.1. 2014.
Ecology of flower smuts (Microbotryum) and their hosts from family Caryophyllaceae
Koupilová, Klára ; Koubek, Tomáš (advisor) ; Marková, Jaroslava (referee)
Anther-smut fungus (Microbotryum spp.) infecting plants of the Caryophyllaceae represents one of the most extensively studied plant pathogen systems. Anther-smut is a pollinator-borne disease that turns infected plants completely sterile. The aim of this thesis is to sum up the main findings about ecology and epidemiology of anther-smut disease and it mainly deals with various factors that influence disease spread and occurrence in nature. According to existing research, abiotic factors play minor role compared to biotic factors and interactions. Among the most pronounced, we can find variability in pathogen virulence and host resistance and also vector behaviour. When studying epidemiology of Microbotryum spp., it is necessary to take account of spatial population structure and metapopulation dynamics as well. Comparing life histories of different host species can also bring useful information. Key words: anther-smut, Microbotryum, Caryophyllaceae, pollinators, resistance, epidemiology, metapopulation dynamics.

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