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Evolutionary forces of Central European taxa of the genus Dactylorhiza
Bílá, Klára ; Urfus, Tomáš (advisor) ; Figura, Tomáš (referee)
Genus Dactylorhiza, comprising green terrestrial orchids, belongs to of the most taxonomically complex groups of Europeran flora. Basic species often hybridise between each other and there is a lot of taxonomically challenging hybrids and hybridogenous lineages. Essential parental species of majority of hybrids and hybridogenous lineages are D. incarnata, D. maculata and D. fuchsii. Sister genus of Dactylorhiza is Gymnadenia which shares some similar features with Dactylorhiza species. Dactylorhiza viridis, formerly classified into the genus Coeloglossum, is the earliest diverged species. Diversity centre probably takes place in the Mediterranean Basin from where Dactylorhiza species migrated back to the Central Europe in postglacial. Major force of the genus evolution is polyploidisation which together with hybridisation leads to establishment of allopolyploid lineages. Unique feature of many orchids (including genus Dactylorhiza) is partial endoreduplication, which somatic endopolyploidisation of certain part of genome takes place. Pollination type is also important for Dactylorhiza microevolution. Deceptive flowers of Dactylorhiza genus are mainly pollinated by naive bumlebees but even beetles or ants can be pollinators. Majority of Dactylorhiza species are threatened by habitat loss during last decades....
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Effect of drought on plant-soil interactions
Secká, Gabriela ; Münzbergová, Zuzana (advisor) ; Florianová, Anna (referee)
There are feedback processes happening between plants and the soil, called plant-soil feedback (PSF), during which the plants affect the physical, chemical and biological properties of the soil and the soil in turn affects not only fitness of individual plant types, but also interspecific interactions. The influence of PSF can manifest either instantaneously or with a delay, and it has a lot of external factors affecting it. The aim of my work was literary research, which focuses on the effects of drought on PSF. Frequent and repeating droughts, which are one of the consequences of climate change, affect not only the processes happening in ecosystems, but also individual organisms present in them, including microorganisms living in the soil. Intense droughts mainly cause temperature increases, decreases in soil moisture and soil degradation. The consequences of the drought include lowering of the primary productivity of plants and changes in the composition of soil and plant ecosystems. These changes, which influence the PSF, manifest as either positive or negative feedback.
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The role of biotic interactions in plant invasions
Štajerová, Kateřina ; Pyšek, Petr (advisor) ; Prach, Karel (referee) ; Richardson, David M. (referee)
- ABSTRACT - The loss of co-adapted and gain of novel biotic interactions during the invasion process influence the success or failure of introduced plants. Within the present thesis, I studied diverse biotic interactions, specifically the relationships between plants and their herbivores, pollinators, fungi, and resident plant communities, and how biotic interactions can be utilized in planning effective science-based management. With my collaborators, we combined the community and biogeographical approach with the reciprocal transcontinental comparison between Eurasia and North America, based on primary data collected in the field. Of numerous hypotheses for the striking success of invasive plants, the enemy release hypothesis (ERH) is one of the most frequently tested. It asserts that the greater performance of introduced plants in non-native ranges is due to the absence, or decrease, in regulation by natural enemies that are left behind in the native range. Our results, in a broad sense, supported ERH, but we found that the magnitude of herbivore damage is context-dependent, related to the feeding guild and origin of both herbivores and plant species and that the increased plant performance in a new range might also be related to other factors, such as the shift in plant competition. Of animal-plant...
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The role of trehalose in mycorrhizal associations
Šoch, Jan ; Ponert, Jan (advisor) ; Hála, Michal (referee)
Mycorrhizal symbiosis is a widely spread phenomenon in nature. A translocation of nutrients occurs between symbionts with disaccharide trehalose playing a key role in the process. However, this saccharide fulfils many important roles in metabolism of fungi and plants. Fungi use trehalose mainly as storage and transport saccharide. On the other hand, trehalose occurs in extremely low amounts in plants where it acts as a signal molecule. Thus it is likely that the saccharide could be used by the fungus to manipulate plant metabolism on a physical interface between symbionts. Trehalose has a similar function in many parasitic interactions. In most cases of mycorrhizal associations trehalose synthesis creates a carbon sink in mycelium which leads to saccharide transfer from the host plant to the fungus. Completely different situation occurs in the types of mycorrhizal symbiosis, where saccharides are translocated from a fungus to a plant. Some plants can utilize trehalose effectively as a sole source of energy. Consequently, the question raises - could such plants gain fungal trehalose on purpose as a source of energy and carbon? This review aims to assess and discuss the mentioned possibilities considering available literature. Key words: mycorrhiza, orchids, parazitism, saccharides, sink, symbiosis,...
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Mycorrhisa in fossil record
Kadlecová, Veronika ; Kvaček, Jiří (advisor) ; Gryndler, Milan (referee)
Mycorrhizal symbiosis is present in the vast majority of extant land plants. Mycorrhizae represent a significant source of nutrients for both partners of the symbiosis and can also provide them with protection or help them survive in less hospitable enviroment. Mycorrhizae is believed to have been just as important in the past and played a major role in evolution of plants, for example in the transition of plants onto land. Mycorrhizal symbiosis is an object of many research works today for its agricultural importance. There is an amount of publications on research of fossil mycorrhizae, but there is still little interest in this issue. Powered by TCPDF (www.tcpdf.org)
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The effect of mycorrhiza on production of plant secondary metabolites
Pikorová, Markéta ; Albrechtová, Jana (advisor) ; Rydlová, Jana (referee)
Mycorhizal symbiosis, mutualistic relationship between symbiotic fungus and plant roots, is ranked among important interspecies interactions. It is indicated that about 90% terrestrial vascular plants live in this symbiosis. Arbuscular mycorrhiza (AM) is the most often occurring type of mycorrhiza and simultaneously the most often occurring type of symbiosis of higher plants. Approximately 80% of all of plant species form this symbiosis. By symbiotic coexistence with fungus plant often gains benefits as for example higher tolerance against stress factors, resistance against pathogens or improvement of nutrient uptake. In recent years in series of works is detected that mycorrhiza positively influences production of plant secondary metabolites. This influence can display quantitativelyby increase of metabolite in plant and also qualitatively by change spectrum of substances produced. These substances can have importance in different spheres for human. Medicinal research regularly extends spectum of substances with bioactive effect which have origin just in the plant secondary metabolism. Target of this thesis is, by the form of literary retrieval, to create an overview of recent state of research regarding of influence of mycorhizal symbiosis on content of secondary metabolites in plants, especially...
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Současné pěstební technologie konopí - vliv na výnos a kvalitu
Josková, Marie
Diploma thesis entitled Contemporary Cannabis growth technology influence on yield and quality in the teoretical part deals with the legislation of cannabis cultivation, agrotechnology of cultivation, harvesting and hemp growing in the Czech Republic, in the European Union and in the world. In the practical part deals with experiments on the influence of arbuscular-mycorrhizal fungi on the content of selected cannabinoids in cannabis plants of the Kompolti and KC Dora varietes in controlled greenhouse conditions at the Institute of Botany of the CAS, v. v. i. and subsequently in the field of Sasov biofarm with Futura, Fibrol, KC Dora and Finola varietes. The effect of inoculation on the increase cannabinoids content has not been demonstrated.
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Choroby dřevin a mykoflóra arboreta Křtiny, ŠLP Křtiny
Riedelová, Adéla Julija
The thesis focuses on woody plant diseases and mycoflora of the arboretum Křtiny. In the period from November 2013 to October 2015 a research was made there using methods of the Czech Scientific Society for Mycology, citizens association. Macromycetes and fungi were observed and their presence is provable by languishing and phytopathological changes of woody plants. For each species substrate and woody plant were marked. In total 62 fungi species were determined. 13 species of mycorrhizal fungi were identified. The thesis also describes diseases and damages that might be caused by fungi pathogens. Findings of fungi were compared to the inventory research made between 1981 and 1984. Introduced woody plants were assessed from the point of view of connection of selected fungi species and their susceptibility to pathogens. Significance of the arboretum as a source of knowledge development and protection of forest ecosystems was evaluated.
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Možnosti využití arbuskulární mykorhizy při rozmnožování vybraných odrůd angreštu
Střihavková, Dana
This diploma thesis deals with usage of arbuscular mycorrhiza in the reproduction of selected varieties of gooseberries in plant nursery. The experiment was established in Brno in autumn 2018 and was completed in spring of the following year. In total, 60 plants of the ´Black Negus´, ´Carat´ and ´Rolonda´ varieties were evaluated, with half of the plants being inoculated with mycorrhizal fungus and the other half without mycorrhiza, as control plants. The following parameters were evaluated: extent of root colonization by mycorrhizal structures, content of chlorophyll, relative size of the root system, dry matter in the root system, substrate temperature and substrate humidity, root collar diameter and shoot length. The results show that inoculation with mycorrhizal fungus influenced the plant root system in positive way, which was reflected in the increase in root collar diameter. The inoculation with mycorrhizal fungus should also have a positive effect on the growth of the aerial part of the plant, the health and plant resistance to drought and pathogens.
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