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Effect of biostimulants on growth and defence reactions in plants
Vlčková, Denisa ; Ryšlavá, Helena (advisor) ; Innemanová, Petra (referee)
Biostimulants are microorganisms or substances of natural origin that promote plant growth and defence against abiotic and biotic stress. The mechanism of action of biostimulants is still a subject of research. In this work, two biostimulants were studied: fermented nettles and vermicompost leachate. Both biostimulants possessed soluble proteins with lower relative molecular weights and peptides, carbohydrates, phenolic substances as well as active proteolytic enzymes and glycosidases. After application of biostimulants to the maize plants (Zea mays L.), growth parameters did not change significantly, but the plants had higher content of proteins and phenolic substances, higher antioxidant capacity and activity of some peroxidase isoforms. The effect of drought on plant growth, metabolism and antioxidant system after application of fermented nettles and vermicompost leachate was also studied. Maize plants under drought stress treated with biostimulants were able to maintain higher water content, showed higher content of proteins, phenolic compounds and higher glutathione reductase activity than untreated stressed control plants. Both tested biostimulants affected the metabolism of drought-stressed maize plants, with the positive effect being more pronounced in the lower-humus soil. Key words:...
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The effect of viral infection on glycosidases activity in tobacco plants (Nicotiana tabacum L.)
Kloudová, Kateřina ; Ryšlavá, Helena (advisor) ; Tichá, Marie (referee)
Glycosidases are widely distributed among microorganisms and fungi, in plants and animals, too. They belong to the hydrolase class, which means that they hydrolyze glycosidic linkages in oligosacharides, polysacharides and other glycokonjugates, as for example glycoproteins, glycolipids or some alkaloids. The role of plant glycosidases has not been made clear till now, so that it is a subject of many studies as well as their characterization. The studied functions are the role during seed germination, during fruit ripening and softening and in defence against biotic and abiotic stress, too. Under biotic-stress, plants synthesize so-called pathogenesis-related proteins (PRP). It was found out that chitinases and β-1,3-glucanaces, which are endoglycosidases, act as PRPs in tobacco leaves. The goal of my work was to find out whether exoglycosidases (α- galactosidase, β-galactosidase, α-glucosidase, β-glucosidase, β-hexosaminidase and α- mannosidase) can also act in defence against biotic stress. I studied the effect of infection in tobacco (Nicotiana tabacum L. cv. Petit Havana SR1) leaves caused by Potato virus Y (PVY) on glycosidases activity. I examined the activity in control and infected tobacco leaves, in both cases the activity of soluble and membrane associated glycosidases was examined. I...
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The effect of Hsp70 protein on the infection caused by Potato virus Y
Doričová, Vlasta ; Hýsková, Veronika (advisor) ; Hoffmeisterová, Hana (referee)
Whithin their natural environment, plants are subjected to a combination of stress conditions. Since potential interactions between signal pathways, plants respond to multiple stresses differently from how they do to individual stresses, activating a specific programme. Heat shock proteins (HSP70) overexpressed after heat shock influence the viral infection. On one side HSP70 can participate on refolding of aggregated or partially denaturated proteins, on the other side HSP70 can interact with viral proteins and facilitate propagation of viral replication complexes. In this work the effect of heat shock (42řC, 2. hours) applied before or after the inoculation of plants Nicotiana tabacum L. cv. Petit Havana SR1 with Potato virus Y on viral infection was detected. This effect was studied in two biological experiments. The amount of coat protein of PVYNTN and protein HSP70 were detected simultaneously with the activity assays of Hatch-Slack cycle enzymes, glycosidases and peroxidase. Both experimental approaches (heat shock applied before or after the inoculation by PVYNTN ) enhanced amount of the virus and in the 2nd experiment it accelerated infection development. Immediately after application of heat shock the amount of HSP70 was increased. The enhancement of HSP70 by viral infection occurred...
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The effect of Hsp70 protein on the infection caused by Potato virus Y
Doričová, Vlasta ; Hýsková, Veronika (advisor) ; Hoffmeisterová, Hana (referee)
Whithin their natural environment, plants are subjected to a combination of stress conditions. Since potential interactions between signal pathways, plants respond to multiple stresses differently from how they do to individual stresses, activating a specific programme. Heat shock proteins (HSP70) overexpressed after heat shock influence the viral infection. On one side HSP70 can participate on refolding of aggregated or partially denaturated proteins, on the other side HSP70 can interact with viral proteins and facilitate propagation of viral replication complexes. In this work the effect of heat shock (42řC, 2. hours) applied before or after the inoculation of plants Nicotiana tabacum L. cv. Petit Havana SR1 with Potato virus Y on viral infection was detected. This effect was studied in two biological experiments. The amount of coat protein of PVYNTN and protein HSP70 were detected simultaneously with the activity assays of Hatch-Slack cycle enzymes, glycosidases and peroxidase. Both experimental approaches (heat shock applied before or after the inoculation by PVYNTN ) enhanced amount of the virus and in the 2nd experiment it accelerated infection development. Immediately after application of heat shock the amount of HSP70 was increased. The enhancement of HSP70 by viral infection occurred...
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The effect of heat shock stress on enzyme activities in plants.
Doričová, Vlasta ; Hýsková, Veronika (advisor) ; Liberda, Jiří (referee)
Heat stress is one of abiotic stress factors, which fundamentally influences the growth and development of plants. Plants response to heat stress by series of cell and metabolic changes, the specificity of heat stress is synthesis of molecular chaperons, called heat- shock proteins (HSP). The influence of heat shock (in the form of 1 hour application of 40řC from 20řC) on the activity of NADP-dependent enzymes, enzymes of Hatch-Slack cycle, glycosidases and the activity of peroxidase in tobacco plants (Nicotiana tabacum L. cv. Petit Havana SR1) was studied in this work. Since HSP are involved in proper folding of immature, misfolded or partly denaturated proteins, in degradation of denaturated proteins and in induction of thermotolerance of plants, the aim of this work was to find out, if the activity of studied enzymes will be maintained or modulated within the plant defense response. The highest amount of HSP70 detected immunochemically together with higher activities of NADP-malic enzyme, phosphoenolpyruvate carboxylase, β-hexosaminidase and α- mannosidase compared to control plants was found 1 hour after application of heat shock. Peroxidase activity was most increased 1 day after HS compared to controls. Using native electrophoresis the differences in isoform content between control and...
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The effect of viral infection on glycosidases activity in tobacco plants (Nicotiana tabacum L.)
Kloudová, Kateřina ; Tichá, Marie (referee) ; Ryšlavá, Helena (advisor)
Glycosidases are widely distributed among microorganisms and fungi, in plants and animals, too. They belong to the hydrolase class, which means that they hydrolyze glycosidic linkages in oligosacharides, polysacharides and other glycokonjugates, as for example glycoproteins, glycolipids or some alkaloids. The role of plant glycosidases has not been made clear till now, so that it is a subject of many studies as well as their characterization. The studied functions are the role during seed germination, during fruit ripening and softening and in defence against biotic and abiotic stress, too. Under biotic-stress, plants synthesize so-called pathogenesis-related proteins (PRP). It was found out that chitinases and β-1,3-glucanaces, which are endoglycosidases, act as PRPs in tobacco leaves. The goal of my work was to find out whether exoglycosidases (α- galactosidase, β-galactosidase, α-glucosidase, β-glucosidase, β-hexosaminidase and α- mannosidase) can also act in defence against biotic stress. I studied the effect of infection in tobacco (Nicotiana tabacum L. cv. Petit Havana SR1) leaves caused by Potato virus Y (PVY) on glycosidases activity. I examined the activity in control and infected tobacco leaves, in both cases the activity of soluble and membrane associated glycosidases was examined. I...
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