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The aim of this thesis is to evaluate the possibility of using sunflower for phytoremediation technologies of soil polluted with over-limiting concentrations of heavy metals. Helianthus annuus L.was selected for our experiments due to its phytoremediation properties. As heavy metals, cadmium, which is abundantly contained in fertilizers, lead, of which concentrations in the environment greatly increased thanks to the using of leaded fuels, and silver, which can be considered as an environmental issue due to its using in nanotechnology, were used. Changes in the activities of chosen enzymes (ALT, AST, urease), concentrations of specific peptides (GSH, GSSG, PC) and the ability to receive and distribute heavy metals were used to evaluate the suitability of plants for phytoremediation purposes.

The theoretical part of this thesis deals with the topic of Plants and Stress describing and discussing not only reactions of plants to acid rains, but also to exposure to other various kinds of stress. The topic of acid rain is discussed in an entire chapter in which the main problems caused by its influence on plants are described. This is followed by a dissection of high-school literature and sources that are focused on the subject. Apart from the theoretical part, the thesis also contains: 1) an explanatory sheet to be used by teachers as a teaching material; 2) students{\crq} worksheets to support teachers{\crq} explanation and to be used as subsequent learning materials; 3) laboratory exercise worksheets designed to lead students during a practical examination; 4) a final test checking what students have learned.

The main goal of the dissertation is to suggest several types of bio-based composites, notably particleboards, made from alternative materials (bio-waste, waste, plants´ residues) as an alternative to the currently produced wooden particleboards. The thesis provides a review and synthesis of the state-of-the-art literature. In the first part the literature is summarized and basic economical and ecological aspects of wood replacements for particleboards by using alternative materials are discussed. Further, mechanical properties data of suggested alternative particleboards are compiled, to give state-of-art insights in alternative particleboards developments. In the state-of-art, the compiled literature data are analysed through Ashby plots and give suggestions on what particleboards properties should be optimized. This evauationhave also proved that particleboards made from plants stalks, wood prunings and other wastes eg. waste tea leaves, peanut hulls, walnut shells could be economically viable alternative for the industry. The second part of this dissertation is concerned with designing and developing particleboards from the alternative resources available in Central Europe: (1) In total, 16 types of particleboards were produced from stalks coming from cup plants, Miscanthus, sunflower and topinambour. These particleboards are specified by standard mechanical tests and the effects of resin content and resin type were studied. Also chemical analysis were performed to determine the cellulose, hemicellulose and lignin contents. Structure of the Miscanthus particleboard were characterized by scanning electron microscopy (SEM). (2) Particleboards were also made and evaluated with different wastes. Particleboard made from BSG (Brewer´s spent grain) were characterized by their mechanical properties, chemical comosition and microscopic structure (SEM). Further, polyethylene terephtalate (PET) waste was added to wooden particleboards. Here, in addition to mechanical properties also microscopic structure and bond failures were analysed using SEM, with air-plasma treated PET particles studied by chemiluminescence and x-ray photoelectron spectroscopy (XPS) for their altered surface chemistry. The final section presents eight particleboard types made from recovered painted wood, as reclaimed from window frames. The effect of painted particles on the physical and mechanical properties were evaluated. With respect to possible applications the most important finding is that all particleboards from plants stalks fulfilled minimal requirements of class P1 in EN 312, which is for general purposes in dry conditions. Furthermore, a three-layer particleboard with spruce surface layers, and a core-layer made from cup-plant would provide a regular appearance of the panel surfaces. Particleboards having 10 % BSG also fulfilled the P1 requirements of EN 312. The particle-particle bonding was found to be a weak point in a entire internal bonding systém. To improve internal bonding experiments with plasma-treated beech wood particles bonded by PVAc was performed. Results have shown a significant improvment of internal bonding due to the plasma treatment. Consequently, the identical plasma treatment was applied to PET particles, which were mixed with wood in the particleboards. Bonding was here improved as well, with the IB higher compared to the untreated control. It was shown that plasma treatment has potential to compensate for declined IB of particleboards using alternative sources. In final part of this thesis, particleboards from reclaimed wood from painted window frames were produced. Results have shown that particleboards using painted-reclaimed wood as well as cleaned reclaimed wood deliver a performance comparable with regular wooden particleboards, as well as reduced thickness swelling.

Plant autophagy is a crucial evolutionary conserved process for recycling cytoplasmic material under stress conditions or during development. The autophagic pathway is negatively regulated by TOR kinase, a versatile molecule modulating a wide range of cellular processes. In mammals, TOR kinase may be activated by phosphatidic acid, a vital signalling lipid. This thesis aims to prove the possible involvement of phospholipids in plant autophagy. I analysed the rate of primary root inhibition in knock-out mutants coding phospholipases in A. thaliana with induced autophagy, measured activity of lipid metabolising enzymes in wild type and atg10 mutant and observed autophagosome formation in selected mutants. Autophagosomes were labelled by fluorescent protein in vivo and by indirect immunolabelling in fixed samples. Using advanced stereological approach, I optimized a method for obtaining an unbiased estimate of autophagosome number in plant root cells.

This dissertation describes the development of new genetic resources of spring barley in a process called prebreeding. Suitable genotypes were detected by using appropriate methods of selection (greenhouse tests, molecular markers, filed tests in provocative conditions). They could be used directly in the next breeding programmes for increased resistance to pathogen Pyrenophora teres f. teres causing net form of net blotch or for improved grain quality usable in the food industry and in nutrition of farm animals.

The goal of this Master thesis was development of teaching materials that are focusing on mastering the fundamentals of mathematical modelling on the examples of photosynthetic processes and influence of selected environmental factors on these processes. Developed models of photosynthetic response to select environmental factors, worksheets, methodical manuals and other supporting materials belong to the teaching materials for secondary schools and serve as a basis of work with models. This teaching materials are aimed to introduce modelling and its significance not only in science but also in education. The present thesis was accomplished on the basis of participation of the Department of Experimental Plant Biology of Faculty of Science of Charles University in Prague in international project NSF within programme GLOBE - The Carbon Cycle. The present thesis is divided into two parts - theoretical part and practical part. The theoretical part includes a literary review and an introduction to the mathematical modelling (in software Stella) that are elaborated considering the teaching purposes and serve as a theoretical background for practical part of present thesis. The chapters that deal with increasing interest in mplementing of modelling in education and with philosophical background of software...

While animal steroid hormones are very well known and have been studied for a long time, in plants no steroid substances were known until relatively recently. Only in the second half of the past century brassinosteroids were discovered; later on, their hormonal function in plants was confirmed. Still a lot of unknown remains as regards their function in plant cells. This paper presents in its first part the evidence that brassinosteroids control in maize (Zea mays L.) grown under field conditions not only its morphology and yield but also some developmental/reproduction characteristics like e.g. number of female inflorescences or speed of the development of male inflorescences. Particular response of a plant depends, however, on the type of applied brassinosteroid, its concentration, and last but not least also on a particular maize genotype and developmental stage of the plant during applicatin. Impact of brassinosteroids on primary photosynthetic processes in plants has not been proven under these conditions, neither on the activity of photosystem (PS) I nor on the Hill reaction. No statistically significant differences in the content of photosynthetic pigments have been found either. Another topic dealt with in this thesis is the possible protective influence of brassinosteroids on plants...

This diploma thesis discusses the possibilities of diversifying the teaching on the issue of germination in the form of worksheets as well as possibility of using germination tests in the inquiry-based teaching of biology at elementary schools and lower secondary schools. The readers are introduced into the general issues regarding seed development, construction and germination. It then deals with iquiry-based teaching, which is one of the most used methods in biology education in recent years. Worksheets created for this purpose are therefore validated through teaching practice and subsequently processed and evaluated. The paper discusses whether germination is a suitable biological material for inquiry-based teaching and also whether these worksheets can be recommended as a didactic teaching material for the development of skills and theoretical knowledge of germination.

Palatability of 20 meadow plant species was assessed in the slug grazing experiment conducted. Monocots exhibited significantly lower palatability than dicots. Litter decomposition rate was assessed in the field litter-bag test. Linear regression analysis was performed to answer the main question whether species palatability is related to litter decomposition rate and whether it is determined by the carbon or nitrogen content. Phylogenetically independent contrasts were used to eliminate correlated phylogeny effect. Regression trees were used to detect the effect of species traits on species palatability and litter decomposition rate.