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The effect of pathogens on invasive plants
Sládečková, Julie ; Koubek, Tomáš (advisor) ; Čuda, Jan (referee)
Invasive plants can destroy entire ecosystems, reduce biodiversity and thus threaten the environment. Number of invasive species is increasing and so their negative impact on the environment. Various reasons can be behind the emergence of invasions, one of them is, for example, escaping from natural enemies. This can make the plant more competitive, have greater reproductive potential and spread better. However, if natural enemies are added to the new area, the number of invasive plants can be regulated. This is the principle of biocontrol, which is a method used to reducing the magnitude of invasions and their consequences. This method has almost no negative impacts on the environment, unlike chemical and mechanical methods of plant removal. Biocontrol has a long-term effect and therefore is also cheaper. However, when biocontrol is used, there is a certain risk that non-target plant species will be affected or that it will not be effective enough. Pathogens are also used as biocontrol agents because they are more specialized than herbivores, so the risk for non-target plants is lower. The aim of this thesis is to compare biological control with other methods used to removing invasive plants and to summarize the most significant positives and negatives of using fungal pathogens in plant biocontrol.
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Biochemical characterization of tomato plants infected with fungal pathogens
Oušková, Marie ; Hýsková, Veronika (advisor) ; Kubíčková, Božena (referee)
Fungal pathogens including Verticillium longisporum which causes verticillium wilt are among the serious diseases of crops that easily spread worldwide. One of the ways to prevent fungal infection is to use fungal biocontrol agents applied as a seed coating. This control agent, the non-pathogenic oomycete Pythium oligandrum, enters the soil together with the seed and acts symbiotically in the plant's root system. On the one hand, it stimulates the plant's defence mechanism by secreting elicitors, and on the other hand, by providing tryptamine, it stimulates growth and increases the plant's fitness with auxin. In this work we studied the effect of seed treatment of Solanum lycopersicum L. cv. Micro-Tom with three different isolates of the genus Pythium (including the commercially used isolate M1 and two yet unused isolates X42 and X48) on the activities of antioxidant and NADP(H)-dependent enzymes in the leaves of plants infected with fungal pathogen V. longisporum. Two weeks after pathogen inoculation, no significant difference was found in the studied enzymes except for increased glucose-6phosphate dehydrogenase and NADP-malate dehydrogenase (oxaloacetate decarboxylation) activity in plants treated with X42 isolate and increased shikimate dehydrogenase activity and antioxidant capacity in plants...
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Stanovení mikroflóry osiva vybraných druhů zeleniny a možnosti ochrany
Chalupová, Lenka
The aim of this diploma thesis is assessing the determination and evaluation of pathogens species spectrum in carrot (Daucus carota), parsley (Petroselinum crispum) and pepper (Capsicum annum) seeds. The microflora was determined in laboratory conditions. The surface disinfected seeds and non-disinfected seeds were cultivated on culture medium PDA and filter paper. The level of bacterial and yeast contamination was low. The major part of pathogenswere fungi pathogens. The most often found pathogens were species from Alternaria and Cladosporium genus. The species spectrum was not different between individual varieties of carrot, parsley and pepper. In most cases, non-disinfected seeds had significantly higher amount of pathogens than the disinfected seeds.
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Hodnocení napadení vybraných odrůd tritikale houbovými patogeny v polních podmínách
Olšanský, Jiří
The bachelor thesis presents results of small-scale experiments with winter triticale on the grounds of Mendel University in Žabčice. Triticale was sown in two variants. One variant was with application of fungicide and the other without. A total of 6 varieties were tested with 3 repetitions. The work compares the fungal pathogen attack on both variants and evaluates other parameters such as yield, 1000 seed weight, plant height, ears per m2, number of grains in the spike and weather conditions. Due to insufficient precipitation, fungal pathogens had poor conditions to spread and yield has been greatly reduced. Untreated variants were slightly infected with Powdery mildew and leaf blights.
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The Usage of Plasma Technologies to Improve the Quality of Feedstuffs
HAVELKA, Zbyněk
The dissertation thesis deals with the problems of the use of plasma technologies in agriculture for the purpose of improving the quality of feedstuffs for agricultural animals. The attention is focused above all on the use of low-temperature gliding arc plasma discharge generated by the atmospheric pressure for the elimination of model fungal pathogens (T. virens) and for the testing of the possibility of the use of plasma for the decreasing of mycotoxin load (DON and D3G). The professional orientation of the dissertation thesis is strongly interdisciplinary with the overlap to the area of the physics of plasma, microbiology, zootechnics and the proposal and construction of technical facilities. With that corresponds also the division of thesis into individual chapters. In the research part, there is a summary of actual pieces of knowledge from the area of fungal microorganisms and mycotoxins produced by these with the view on their presence in feedstuffs. There follows a research of pieces of knowledge of low-temperature plasma and its applications in the food industry and feeding. In the chapter Material and Methodology, the applicated methods of work, employed instruments and biological material are described. The resulting part is, for its clear arrangement, divided into five subchapters ? stating of selected parameters of plasma device, influence of plasma on nutritional parameters, influence of plasma on the model fungus Trichoderma virens and possibilities of the use of plasma discharge for the decreasing of concentration of mycotoxins in feedstuffs. The final part is dedicated to the description of system which enables the treatment of samples in continuous regime. The treatment of mycelial discs by plasma discharge lead to the decrease of germination capacity of spores of fungi, while there was experimentally proven the synergic effect of the influence of individual mechanisms by which the plasma interacts with the surface of biological material. At the same time, there was not observed a more significant change in the composition of feedstuffs, more significant is only the change of humidity of sample. In the laboratory conditions, the decreasing of concentration of mycotoxins spread on laboratory glass was proven. At the samples of feedstuffs contaminated by natural way, it was not successful to reliably provedecreasing of concentration of mycotoxins in a sample as a result of plasma activity.
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Vliv mikroklimatu a půdních vlastností na výskyt listových patogenů ječmene v zemědělském podniku
Stošek, Lukáš
Diploma thesis is aimed at influence of microclimate and soil properties on occurrence of the barley leaf plant pathogens. The attention is devoted to parasitic fungi of barley Pyrenophora teres, Pyrenophora graminearum, Ramularia collo cygni and Rhynchosporium secalis. The early determination of plant disease leads to possibilities of control and in this way to keep harmful agent under economic damage threshold. The evaluation of occurrence of fungal pathogens on three localities with different microclimate and soil properties comprises the part of my work. Three barley varieties Malz, Francin and Bojos were evaluated and compared from the point of view of susceptibility to fungal pathogens, subsequently. The evaluation was carried out on the farm HESAKO s.r.o Velké Heraltice in Moravian Silesian Region. The occurrence and development of particular pathogens was under economic damage threshold in the year 2015 in dependence of variety resistance, good plant disease practices and course of the weather.
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Možnosti ochrany voči hubovým chorobám v podmienkach ekologického vinohradníctva a vplyv na kvalitu hrozna
Rajčoková, Michaela
This bachelor`s thesis says about the protection against fungal pathogens in terms of ecological viticulture in the first place. It also contains characteristics of the most important mycoses of grapevine (Vitis vinifera ssp). It introduces definition of the ecological viticulture and its development. In comparison with other advanced countries, the Czech Republic has a high ratio of ecological viticulture. Furthermore, this work proceeds the factors affecting a quality of grapes -- essence of the proper microclimate, importance of greenery and soil ,,renewal", and the effect of defoliation. In the end of the work there is an characterization of ecological preperations against fungal diseases, its quantisation and its positive effect on grapevine immunity.
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