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Measurement of predator effectiveness by means of cage exclusion experiments
Fischerová, Laura ; Kindlmann, Pavel (advisor) ; Tropek, Robert (referee)
1 Abstract Cage exclusion experiments are used in ecological and agricultural studies to determine plant- insect interactions (Kidd & Jervis 2005). Cages are used to detect the insect density on the plant, while other influences such as natural predators or other pests are excluded. Exclusion of predators by using physical barriers (different mesh size) is one of the most used ways to determine the impact of natural enemies on the pest population. The results of these experiments suggest, that the pest population on caged plants, from which natural enemies are excluded, has a lower percentage of mortality and parasitism than the population on plants, where the natural enemies have full access to (Luck et al. 1988). Results of this method are used in programs of biocontrol when searching optimal plant treatments and possible alternatives instead of using insecticides (Lawson et al. 1994). The question is, whether cage exclusion experiments are adequately reflecting changes in pest populations and their impact on plants. As a result of caging the area, changes in microclimate and plant growth occur, which subsequently affects present insect populations. Cages do not also allow leaving the pests from the cage and, in some cases, unwanted natural enemies enter them, even though they have been previously...
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The impact of herbivores on plant population dynamics: The importance for biological control of invasive plants
Šulcová, Hana ; Dostál, Petr (advisor) ; Kindlmann, Pavel (referee)
Herbivory is one of the most important relations between plants and animals. The herbivores affect plant populations not only by grazing, but also by trampling and disturbing the vegetation. Herbivores have also great potential to affect the population dynamics of particular plant species. The aim of this thesis is to evaluate the effect of herbivores on plant population dynamics and to interpret it in relation to biological control of invasive plants. When evaluating the effect of herbivores, it is necessary to keep in mind the fact that herbivores don't affect only plants but also each other through direct as well as indirect competition. The use of different herbivore species to supress the invasive plants may not necessarily be effective. The range of the effect of herbivores on plant population dynamics depends also on the environmental conditions. Habitats with infrequent disturbances and high competition levels among plants increase the effect of biological control, because high competition facilitates competitive exlusion of the target plant species. Different life-histories of plants play are also important in terms of biological control mainly the life-span and the endurance of the seed bank affect the results. Monocarpic species with short-lived seed bank can be relatively easily reduced by...
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Inhibitory effects of B. velezensis strain on plant pathogens of the genus Xanthomonas
Švecová, Magdaléna ; Palyzová, Andrea (advisor) ; Jelínková, Markéta (referee)
Biological control is a method of applied ecology that uses one organism, or its product, to inhibit another pathogenic organism. This method in plant protection should be more environmentally friendly than commonly used pesticides. The rhizobacterium Bacillus velezensis FZB42, which can suppress the growth of other microorganisms, can be used as a biological control agent. Xanthomonas campestris pv. campestris is a phytopathogen that causes significant losses in agricultural production. This diploma thesis proved an antagonistic effect of the bacterial strain B. velezensis FZB42 on the phytopathogenic bacteria Xanthomonas campestris pv. campestris SU in mixed culture. The study confirmed that the antibiotic effect of B. velezensis strain FZB42 against X. campestris pv. campestris SU in mixed culture depends on the inoculation ratios of both strains. The interaction of the two bacterial strains was characterized by metabolomics analysis, it was confirmed that B. velezensis FZB42 produces four dominant secondary metabolites: lipopeptides surfactin, fengycin, and bacillomycin and siderophore bacillibactin, which show antifungal and antibiotic activity. The inhibitory activity of B. velezensis strain FZB42 was further monitored by SEM analysis, which showed damage to X. campesris pv. campestris SU...
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Role of true bugs in a lifetime of humans
CHALOUPKOVÁ, Věra
This bachelor thesis covers the theme of the role of true bugs in human life. The aim of this bachelor thesis is to create a brief research focusing on true bugs as human and livestock parasites, pests of crops cultivated by humans, their function in biological control, their use in laboratory research and in food, as well as their occurrence in literature, television programs, music and as an inspiration for artworks and various products
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Measurement of predator effectiveness by means of cage exclusion experiments
Fischerová, Laura ; Kindlmann, Pavel (advisor) ; Tropek, Robert (referee)
1 Abstract Cage exclusion experiments are used in ecological and agricultural studies to determine plant- insect interactions (Kidd & Jervis 2005). Cages are used to detect the insect density on the plant, while other influences such as natural predators or other pests are excluded. Exclusion of predators by using physical barriers (different mesh size) is one of the most used ways to determine the impact of natural enemies on the pest population. The results of these experiments suggest, that the pest population on caged plants, from which natural enemies are excluded, has a lower percentage of mortality and parasitism than the population on plants, where the natural enemies have full access to (Luck et al. 1988). Results of this method are used in programs of biocontrol when searching optimal plant treatments and possible alternatives instead of using insecticides (Lawson et al. 1994). The question is, whether cage exclusion experiments are adequately reflecting changes in pest populations and their impact on plants. As a result of caging the area, changes in microclimate and plant growth occur, which subsequently affects present insect populations. Cages do not also allow leaving the pests from the cage and, in some cases, unwanted natural enemies enter them, even though they have been previously...
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Biology and taxonomy of Anaphes flavipes (Hymenoptera: Mymaridae) and potential use for biological control
Samková, Alena ; Janšta, Petr (advisor) ; Holý, Kamil (referee)
My master thesis deals with biology and morphology of the species Anaphes flavipes (Chalcidoidea: Mymaridae) and its potential use for biological control of leaf beetles. Particularly, the fitness of wasps was studied and a statistically significant difference in number of parasitize host eggs for mated females compared to non-mated. The effect of feeding parental population on the number of parasitized host eggs, the number of offspring in F1 generation or their sex ratio, was not proved. Study of host specificity of A. flavipes indicates preference for host eggs of species Oulema melanopus. Preference for heavier host eggs was not confirmed. The effect of host eggs weight on number of eggs wasps inside was not conclusive either. Length of parasitism of host eggs was consistent with earlier studies. The passive defense of host O. gallaecina against parasitoid was observed. Variability of the species depending on location, host, nutrition, etc. was determined using morphological measurements. The third part of the thesis is focused on population density of A. flavipes and its hosts in the localities of organic versus conventional farming in order to use the parasitoid for biological control. There was no significant difference in the size of pest and parasitoid populations between the types of agriculture....
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The impact of herbivores on plant population dynamics: The importance for biological control of invasive plants
Šulcová, Hana ; Dostál, Petr (advisor) ; Kindlmann, Pavel (referee)
Herbivory is one of the most important relations between plants and animals. The herbivores affect plant populations not only by grazing, but also by trampling and disturbing the vegetation. Herbivores have also great potential to affect the population dynamics of particular plant species. The aim of this thesis is to evaluate the effect of herbivores on plant population dynamics and to interpret it in relation to biological control of invasive plants. When evaluating the effect of herbivores, it is necessary to keep in mind the fact that herbivores don't affect only plants but also each other through direct as well as indirect competition. The use of different herbivore species to supress the invasive plants may not necessarily be effective. The range of the effect of herbivores on plant population dynamics depends also on the environmental conditions. Habitats with infrequent disturbances and high competition levels among plants increase the effect of biological control, because high competition facilitates competitive exlusion of the target plant species. Different life-histories of plants play are also important in terms of biological control mainly the life-span and the endurance of the seed bank affect the results. Monocarpic species with short-lived seed bank can be relatively easily reduced by...
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Confirmation of \kur{Beauveria caledonica} occurence in Šumava National park by molecular markers
BINDER, Richard
Biological plant protection against insect pests is an important alternative to chemical protection. One of the most important group used in the biological plant protection against insect pests are the entomopathogenic fungi. Entomopathogenic fungi are microscopic fungi that are able to induce a primary disease to insect pests. It is a very heterogeneous group of species. Worldwide there were isolated and described more than 750 species of entomopathogenic fungi. Genus Beauveria is considered one of the most important genera of entomopathogenic fungi. In the Czech Republic there has been confirmed species B. bassiana, B. brongniartii and now, on the basis of this work, B. caledonica. This study is aimed to confirm the occurrence of B. caledonica in National Park Šumava. To confirm this occurrence, I used analyzes based on the methods of molecular markers. Molecular markers are an indispensable part of science in the field of mycology, for example the strain characterization, population genetics, detection and identification of fungi, phylogenetic studies and evolutionary biology. For this study there were used sequence analysis of ITS, EF1- and LSU regions. The output data of these analyzes were used to create phylogenetic trees. The result of my thesis is taxonomical classification of studied isolates on species level.
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Polymorphism of microsatellite markers in selected \kur{Beauveria bassiana} strains/isolates
KRÁLOVÁ, Martina
\kur{Beauveria bassiana} is a entomopathogenic polyphagous fungus commonly found in soil and it is parasite of soil insects, mainly of the stages of insect that occur in soil. At the present time it is used in plant protection against more than 70 species of insects. In the Czech Republic \kur{Beauveria bassiana} has the greatest importance in the fight against bark beetle \kur{Ips typographus} in the NP Šumava in these days. This study was focused on the evaluation of genetic variability \kur{Beauveria bassiana} strains on the basis of microsatellite analysis and the comparison of four separation methods: electrophoresis in 2% agarose gel, electrophoresis in 3% synergel, chip electrophoresis and fluorescent capillary electrophoresis in term of the most precise separation of PCR products. We used 41 strains which were collected in the NP Šumava and 20 strains from long-term collection determined as an exotic in this study. This large geographical scale group contains the strains from whole world and in addition it was upgraded by the strains collected from the NP Krkonoše and South Moravia. For the microsatellite analysis there were used 11 pairs of primers but for inter-comparison of separative methods were chosen only 4 pairs of primers. The population of \kur{Beauveria bassiana} strains collected from the NP Šumava were evaluated by analysis of microsatellites as a conservative and fully closed regardless of the source and the location. The strains from the large geographical scale group showed the great genetic variability. In terms of separation, the best and most suitable separation method was proved, the fluorescent capillary electrophoresis. Despite of its difficult financial aspect, this method was evaluated as the most precise and the most sensitive. Its advantage is in possibility to detect the smallest differences in the length of single allele in the range 1-2 bp, which is for the gel electrophoresis impossible.
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The study of suppression fungus S.sclerotiorum by the mycoparasitical fungus C.minitans
BÍLKOVÁ, Jana
This work is conceived as literary overview,summary new knowledge from the suppression of the phytopatogenic fungus S.sclerotiorum by the mycoparasitical fungus C.minitans.Key is sight on charakteristic the fungus C.minitans,S.clerotiorum and the genus Trichoderma.An important Material for findings the suppression S.clerotiorum by differnet genus the mycoparasitical fungus C.minitans become laboratiry test"in vitro",that assessed growth and production properties of the fungus C.minitans.The results this work should serve to objective assessment and verification of options use the mycoparasitical fungus C.minitans in biological control of plant agains S.sclerotiorum.
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