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Carbohydrate metabolism under increased CO2 concentration in the environment
Bardoňová, Radka ; Lhotáková, Zuzana (advisor) ; Tomášková, Ivana (referee)
This Master thesis deals with the effect of elevated atmospheric carbon dioxide concentration ([CO2]) and irradiation on the content of nonstructural carbohydrates of European beech (Fagus sylvatica L.) leaves and Norway spruce (Picea abies Karst.) needles. Nonstructural carbohydrate content reflects the balance between carbon assimilation and utilization. Elevated [CO2] usually causes increase in the assimilation rate and changes in processes, in which assimilated carbon is utilized. These changes are often accompanied by increase of nonstructural carbohydrate levels - soluble carbohydrates and starch. Material used in this thesis comes from experimental site of the Global Change Research Institute (GCRI) AS CR at Bílý kříž in the Beskydy mountains. Juvenile European beech and Norway spruce trees grown in a closed canopy were treated by elevated [CO2] (700 ppm) for six growing seasons. The samples were taken in two different times of the vegetation season from sun exposed and shades leaves and needles. The carbohydrate content and spectra were determined using high performance liquid chromatography. Supplemental short-term experiment focused on the diurnal dynamics of nonstructural carbohydrate content was performed using juvenile spruce trees growing for four weeks in fully controlled conditions...
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Thorium as an environment stressor for plant growth.
Hrdinová, Aneta ; Lhotáková, Zuzana (advisor) ; Podlipná, Radka (referee)
Thorium is an element belonging to heavy metals, which is characterized by its radioactivity similarly to uranium and radon. Thorium is not commonly used in industry, but becouse of its radioactive properties it has a great potentional for future use in nuclear energetics. Thus, increasing release of Th into the soil, water and atmosphere can be expected in near future and through plant biomass it could become a part of food chains and webs and, thus, to represent a considerable health risks to humans. Studies devoted to research on thorium and its effects on plants has not been published much yet. The majority of these studies focus mainly only on plant abilities to accumulate thorium and/or monitoring distribution of thorium in plant body. But till now, a study is still missing, which would monitor the effect of thorium on the physiological characteristics of plants. Plants of Nicotiana glutinosa (L.) medium Thorium accumulatin were hydroponically cultivated Hoagland nutrient media differedin the presence of thorium, tartaric acid, putrescine and phosphates. In first part of the present study I monitored accumulation of thorium by tobacco plants under the influence of the above-mentioned modifications of media. In the second part, I studied the Th effect on the photosynthetic apparatus (contents...
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Abiotic Stress Adaptation in Plantago: mechanisms of tolerance
Dvořáková, Iveta ; Konrádová, Hana (advisor) ; Lhotáková, Zuzana (referee)
Plants are exposed to many adverse factors during their life cycles. Abiotic stresses are significantly limiting plant growth and development. Abiotic stress response mechanisms involve compatible solute synthesis (e.g. sugars, sugar alcohols and amino acids). The aim of this study was to characterise the responses of plants from Plantago genus to different abiotic stresses (drought, salinity, cold and stress combination). The complete plants grew under in vitro conditions. I compared morphological parameters, selected metabolic parameters (carbohydrates balance and proline accumulation) under optimal conditions and stress exposure. This study was focused on plants from genus Plantago, because they differ from each other in their tolerance to the salinity. Both, the glycophyte and the halophyte species are described within this genus. Plantains produce besides widespread soluble carbohydrates (sucrose, glucose, fructose) also sugar alcohol sorbitol, which has been reported as a significant component of the stress response. In addition, the reaction of plants to different carbon and energy sources was tested. More severe growth inhibition of the glycophyte Plantago lanceolata compared to the halophyte P. maritima was observed under salt treatment. Significant accumulation of sorbitol was observed...
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Comparison of various approaches to evaluation of tree energetic balance
Tomková, Alžběta ; Pokorný, Jan (advisor) ; Lhotáková, Zuzana (referee)
The thesis deals with the tree energetic balance closely related to the phenomenon of plant transpiration. Living systems have a unique ability to equilibrate gradients in the nature. Storing energy of the incoming solar radiation into a latent heat of water evaporation is an example of such tree feature. It dissipates energy and simultaneously recycles nutrients and water in the ecosystem. There are few possible ways of energy balance detection shown in this work. The thermal imagining can be used as a method for an indirect indication of transpiration - transpiring plants have lower leaf surface temperature. An alternative method for determining the rate of transpiration is a direct measurement of transpiration on leaves or transpiration flow in a tree trunk. However, extrapolation of the above mentioned methods to entire stands can encounter some difficulties. The first part of the thesis presents a description of a physical background of energetic processes and the ways in which plants operate with water, the biotic pump theory is being discussed. The practical part begins with experiments on single leaves. These experiments are carried out to test the usability of the methods for the following experiments, which are performed on the entire living trees. They are focused on the relationship of the...
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Physiological mechanisms of sorghum adaptation to abiotic stresses
Kratochvíl, Jan ; Konrádová, Hana (advisor) ; Lhotáková, Zuzana (referee)
Sorghum is a traditional crop, which has been grown especially in the countries of Africa and Asia. It is used as a food, fodder, source of fiber and energy. Because of its tolerance to various abiotic stresses, especially drought, sorghum is often called "the camel of crops", and there are a lot of studies trying to clarify the basis of this tolerance. Nowadays, suitable sorghum genotypes are considered as an alternative in other parts of the world (North and Middle America, Europe) or to widen the planting areas. The first part of this thesis summarizes results of current studies aimed on sorghum physiological responses to drought, high salinity, extreme temperatures, aluminium toxicity and the combination of these stresses. The second part explains the ways how to alleviate effect of stresses on the plant. It includes the application of various compounds and genetic modifications. Powered by TCPDF (www.tcpdf.org)
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The role of NO in plant senescence
Kramná, Barbara ; Wilhelmová, Naďa (advisor) ; Lhotáková, Zuzana (referee)
1 Abstract Nitric oxide (NO) is a lipophilic free radical gaseous molecule able to readily diffuse through membranes and thus influence the adjacent cells from its source. It belongs among important physiological modulators of a plant life despite of its short life span, which is in most cases, only a few seconds. NO influences plants during their whole life cycle and predominantly acts via a modulation of gene expression or post-translation modifications. An enzymatic production of NO has been documented in apoplast, cytosol and organels such as mitochondria, chloroplasts and peroxisomes, apart from its spontaneous production in reducting conditions. The possible cytoprotective or cytotoxic effects of NO in plant cells depends on its concentration. High concentrations have been proved to be rather cytotoxic. Plant senescence is often accompanied by a vast oxidative damage, which results in high concentrations of ROS, such as O2∙- and H2O2, lipid peroxidation and a decrease of antioxidant enzymes activities. NO has been proved to retard or entirely prevent a senescent phenotype of stress-treated plants. Thus a role as a negative regulator of plant senescence has been proposed for it. The most often method used for NO level modulation in plant tissues is an exogenous aplication of various NO donors. Other...
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The effect of uranium on carbohydrate metabolism of cultivated plants.
Lábusová, Jana ; Lipavská, Helena (advisor) ; Lhotáková, Zuzana (referee)
Nowadays, the environmental pollution by heavy metals is very serious problem all around the world. Radionuclides, including uranium, are heavy metals that cause both chemical and radioactive pollution. Naturally occurring uranium is not so dangerous for living organisms. Human activities, especially uranium ore mining and use of phosphate fertilizers, have increased its concentration in the environment with consequent contamination of soil, water and air. Compared to other countries, the Czech Republic is relatively rich in deposits of uranium ore. Extensive mining results in large contaminated areas, containing not only uranium but also other heavy metals and xenobiotics that need to be removed from the environment. One way how to decontaminate soils and waters is phytoremediation. This eco-friendly and cost-effective technique exploits the ability of plants to take up, translocate, transform and sequester xenobiotics. In order to provide functional phytoremediation, it is necessary to understand the mechanisms of plant responses to stress caused by xenobiotics. Therefore in my master thesis, I focused on the impact of uranium on physiological processes of uranium-stressed plants, with the emphasis on carbohydrate metabolism and antioxidative defense mechanism. Powered by TCPDF (www.tcpdf.org)
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Anatomical study of shade and sun European beech leaf under elevated CO2.
Horská, Jana ; Lhotáková, Zuzana (advisor) ; Urban, Otmar (referee)
The present Master thesis focuses on evalution of CO2 concentration and irradiance on selected leaf anatomical parameters of European Beech (Common Beech) Fagus sylvatica L.. The process of photosynthesis is remarkably determined by numerous extrenal factors, among them by atmoshperic CO2 concentration and irradiance and is closely correlated with leaf anatomical parameters. One of these most important anatomical parameters affecting the net assimilation rate is an internal leaf surface, which corresponds to mesophyll area avialable for gas exhcange. Experimental material of the study was sampled from the leaves of juvenile trees of F. sylvatica planted in 2005 and growing under ambient (390 ppm, AC) and elevated (700 ppm, EC) CO2 concentrations on the experimental site of the Global Change Research Center AS CR at Bílý Kříž in the Beskydy Mountains. Sun and shade leaves were sampled from trees of both CO2 treatments in two seasons 3 years apart (2009 and 2012). To determine leaf anatomical parameters, the stereological methods were applied, which yield unbiased estimation of measured parameters, particularly the Fakir method for internal leaf surface determination. The EC effect was observed on the leaves sampled in 2009 only in the decrease of proportion of intercellular spaces in mesophyll. In...
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Lateral root development in response to mineral nutrients; signal mechanisms and pathways.
Halamková, Daniela ; Tylová, Edita (advisor) ; Lhotáková, Zuzana (referee)
TTL3 gene was identified by forward screening of genes involved in lateral root development in Arabidopsis thaliana based on its expression pattern. TTL3 belongs to the TTL (TETRATRICOPEPTIDE-REPEAT THIOREDOXIN-LIKE) gene family. The diploma thesis is aimed on characterisation of changes in TTL1, TTL3 a TTL4 promotor activities in response to external conditions (availability of nitrogen or phosphorus) that affect root growth. Obtained data should elucidate possible relation among TTL gene expression activities, root growth rate, and apical meristem activity. Nitrogen or phosphorus deficiency triggered changes in root growth and root system morphology of experimental plants. Short-term nitrogen deficiency stimulated root growth. Short-term phosphorus deficiency induced gradual growth cessation in main root and long laterals. Long-term deficiency reduced root growth of both N-deficient and P-deficient plants compared to control. The root system size of N-deficient and P-deficient plant was almost similar. Determination of promotor activity using β-glucuronidase reporter gene showed changes in expression activity and its localization in response to root growth intensity. TTL4 gene promotor activity was the most responsive. Its activity was generally higher in slowly growing roots, particularly under...
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GM crops and the third world
Andrová, Julie ; Opatrný, Zdeněk (advisor) ; Lhotáková, Zuzana (referee)
The inhabitants of the Third World have to deal with problems such as population explosion, undernourishment, poverty and morbidity. The Green Revolution saved millions of people from hunger through the introduction of specially bred varieties of cereal in combination with mineral fertilization. The transition from the Green Revolution to the Genetic Revolution, which consists in the introduction of transgenic crops prepared using genetic engineering techniques, could represent the future for developing countries. The work deals with the issue of transgenic crops in developing countries. The first part deals with problems of the Third World, the second part with transgenic crops, specifically the preparation process of these crops, their present and potential use in developing countries and potential risks. The third part includes analysis of the Framework Education Programme for Secondary General Education and analysis of selected textbooks.
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