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Use of biochemical methods in the study of plant metabolism with emphasis on the defense system
Bělonožníková, Kateřina ; Ryšlavá, Helena (advisor) ; Luhová, Lenka (referee) ; Plchová, Helena (referee)
As sessile organisms, plants cannot avoid being exposed to various biotic and abiotic stress factors. To defend themselves plants have developed complex and sophisticated defense mechanisms. In agriculture, pesticides are used for plant protection, but they can have undesirable side effects, and therefore attention is being paid to biological control agents. One such agent is Pythium oligandrum, a soil oomycete that has a positive effect on plants at several levels. On the one hand, it secretes elicitins, which stimulate defensive responses and prepare the plant for possible infection (i.e., priming effect), and on the other hand, it produces tryptamine, a precursor of auxin, thus supporting the plant's growth. Furthermore, P. oligandrum directly acts as pathogen mycoparasite or evokes antibiosis, or competition for nutrients and space with other microorganisms. The key research topic of this thesis was the analysis of the biochemical properties of eleven Pythium strains and their impact on plant metabolism. Our results showed that even closely related P. oligandrum strains significantly differ in the content of compounds secreted into the medium, including proteins, amino acids, tryptamine, and hydrolytic enzymes capable of degrading cell walls (endo-β-1,3-glucanase, chitinase, and cellulase),...
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Use of biochemical methods in the study of plant metabolism with emphasis on the defense system
Bělonožníková, Kateřina
As sessile organisms, plants cannot avoid being exposed to various biotic and abiotic stress factors. To defend themselves plants have developed complex and sophisticated defense mechanisms. In agriculture, pesticides are used for plant protection, but they can have undesirable side effects, and therefore attention is being paid to biological control agents. One such agent is Pythium oligandrum, a soil oomycete that has a positive effect on plants at several levels. On the one hand, it secretes elicitins, which stimulate defensive responses and prepare the plant for possible infection (i.e., priming effect), and on the other hand, it produces tryptamine, a precursor of auxin, thus supporting the plant's growth. Furthermore, P. oligandrum directly acts as pathogen mycoparasite or evokes antibiosis, or competition for nutrients and space with other microorganisms. The key research topic of this thesis was the analysis of the biochemical properties of eleven Pythium strains and their impact on plant metabolism. Our results showed that even closely related P. oligandrum strains significantly differ in the content of compounds secreted into the medium, including proteins, amino acids, tryptamine, and hydrolytic enzymes capable of degrading cell walls (endo-β-1,3-glucanase, chitinase, and cellulase),...
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Modern fungicides and mechanism of their action
Zaleš, František ; Gabriel, Jiří (advisor) ; Ptáček, Petr (referee)
Fungicides are compounds, which are able to kill a fungi (they are therefore fungicidal), or they are able to slow or stop growth of a fungi (they are therefore fungistatic). Some fungicides also have insecticidal properties and can offer dual protection. This bachelor thesis is mainly dealing with fungicides, which are used to protect wood and wooden constructions from wood decaying fungi. Part of this bachelor thesis is a brief overview of wood decaying fungi and also an insight into the history of fungicides, but the main goal of this thesis is to offer a survey of currently used fungicides for wood protection against wood decaying fungi and also describe the mechanism of their action. Keywords: fungi, fungicides, buildings, general threat, wood decay, mode of action
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Monitoring of selected metals in comercial bio wines
Bortlová, Alžběta ; Reichstädter, Marek (referee) ; Pořízka, Jaromír (advisor)
This bachelor thesis is focused on monitoring of selected metals in commercial organic wines. The aim of this thesis was to compare element content of organically produced wines with wines originating from other agrotechnical production system. Optical emission spectrometry with inductively coupled plasma (ICP-OES) was used for element analysis of wine. Statistical method analysis of variance has been used to assess whether the concentrations of the elements showed statistical differences between wines originating from organic production and wines originating from other production systems. Statistical differences were found in 3 of 20 analysed elements. Correlations between the element analysis and type of production system of grapevine were observed in content of the zinc, nickel and manganese.
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Influence of Fungicide Thiram on Chlorophyll Content and on the Growth of Garden Strawberry (Fragaria Annanasa)
Jakl, M. ; Jaklová Dytrtová, Jana ; Navrátil, Tomáš ; Marková, A.
Thiram is a relatively frequently used fungicide in agriculture and gardening. However, its behavior in environmental systems has not been elucidated in detail up to now. The effect of thiram presence in three different soil types on the yield and chlorophyll contents in garden strawberry plantation was investigated. It is possible to conclude that its presence in soil significantly increased the chlorophyll a and b contents in slightly acidic soil from Humpolec location. The changes of investigated parameters could be ascribed to supported mobilization of Mg, acting together with other nutrients mobilized in low pH of soils. The yield decreased addition in all tested soil types under thiram application.
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Study of tebuconazole complexes with metal ionts
Norková, Renáta ; Jaklová Dytrtová, Jana (advisor) ; Vyskočil, Vlastimil (referee)
Tebuconazole belongs to widely utilized plant fungicides, mostly in vineyards. Its traces are present in plant tissues, wine as well as in soil. The aim of the study was to determine stoichiometries and stabilities of metal (Cu, Zn, Cd, Ca and Ag) complexes with tebuconazole (1) by means of electrospray ionization mass spectrommetry (ESI-MS). It was found that the complexes of tebuconazole with copper ions are particularly stable ([Cu(1)]+ has appearance energy 224 kJ·mol-1 , corresponding with the dissociation of the water molecule from the tebuconazole molecule), while the stability of another tebuconazole complexes is lower, about 150 kJ·mol-1 . In real environmental samples, the detection of 1 itself is hampered by its spreading into various species. The method involved here is based upon a hyphenation of electrochemistry (amperometry) and electrospray-ionization mass spectrometry (ESI-MS). It uses the fact that Cu creates very stable complexes with 1. We demonstrate that at appropriate potentials (at higher than 500 mV) Cu cations can be generated in an electrochemical cell and subsequently form complexes with 1 present in the sample. The resulting complex [Cu(1)]+ is detected with ESI-MS. The intensity of detected complexes depends on the concentration of 1 and the oxidation level of the...
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Determination of residues of the selected pesticide effective substances in wine using the GC/MS method
Ehrenbergerová, Martina ; Benešová, Karolína (referee) ; Mikulíková, Renata (advisor)
The grape is one of the oldest cultivated plants. It can be consumed as a fruit or it can be used as a raw material for making stews, juices or the cultivated drink – wine. Generations of wine-makers have been striving to improve both the cultivating conditions of vineyards and the quality of wine. Many harmful elements, such as herbivorous pests, diseases and storms are important factors that can have a negative impact on crop quality. To regulate the effects of these factors, an integrated protection system is used, incorporating agronomical measures, resistant varieties and a wide spectrum of pesticides. However, increasing the usage of pesticides brings certain dangers to both the production quality and the environment. This necessitates the monitoring of the negative effects, including the content of pesticide residues in the grapes. My thesis studies and experimentally assesses selected pesticide residues in certain wine samples.
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Multiresidual methods for the determination of pesticides in waters
Matušková, Monika ; Kubíčková, Kristýna (referee) ; Vávrová, Milada (advisor)
This bachelor´s work of theoretical character deals with multiresidual determination of pesticides in water. It is especially focused on pesticides generating residues in surface water, which - due to their toxicity and persistence in environment - require goal-directed monitoring. The division of pesticides is stated, and their properties, toxicity and elimination process are described in the work. Furthermore, possibilities of analytical determination, especially the methods of gas and liquid chromatography are introduced here. In the last chapter, the complete analytic procedure for determination of organochlorine pesticides is described.
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Possibilities of pesticide degradation by titanium dioxide
Píšťková, Veronika ; Veselý, Michal (referee) ; Vávrová, Milada (advisor)
The aim of this bachelor´s thesis is a selection of pesticides, which could be degradated using titanium dioxide. The first part of the paper deals with general pesticide characteristics, subdivision of pesticides, mode of action on target agents and transformations of pesticides within the environment – the metabolic and the non-metabolic tranformation. The second part of the paper deals with heterogeneous photocatalysis using semiconductor TiO2, which is activated by ultraviolet or solar radiation. Using this method pesticides could be transformed even into carbon dioxide, water and inorganic mineral salts. Furthermore, there are mentioned the factors, which affect degradation rate, analytical methods to determine kinetics of degradation and methods for monitoring transients and end products. By each group of pesticides there are stated the representatives from this group, which have been used for investigation of degradation methods. Furthermore are mentioned decomposition mechanisms of reaction and the intermediate products formed during the photocatalysis process.
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Multirezidual analysis of selected pesticides in barley
Ehrenbergerová, Martina ; Duroňová, Kateřina (referee) ; Mikulíková, Renata (advisor)
Barley is one of the economically important crops. Its production is primarilly used as fodder barley and also in brewery and food industry. Particularly the part of its production intended for malt production must be of high quality. There are some important factors which can influence the quality of the crops, such as harmful organisms – diseases, pests and weed. In order to regulate the occurence of harmful organisms, agricultural measures are taken in the integrated protection system and resistant variants and pesticides are used. The higher the demand on the production quality, the bigger is the volume and the spectrum of pesticides used. The increasing extent of pesticide use also poses a risk for internal production quality and the environment. This fact makes it necessary to monitor unfavourable influences, including the contents of the pesticide residues in barley. This work studies the possibility of multiresidual determination of some selected pesticides in malting barley.
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