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This study deals with the bioaccumulation of scarce metals, especially lanthanides, contained in red mud. The effect of red mud is studied on cultures of La4 mutant of the green alga Desmodesmus quadricauda and on red microalga Galdieria sulphuraria under different metabolic regimes with the addition of acidic extract of red mud.

The family Pyrolaceae (pyroloids) includes the group of evergreen herbs or subshrubs growing in coniferous, especially in pine forest of the northern hemisphere. Their typical features are mycoheterotrophy and mixotrophy. In the early stage of development the mycoheterotrophy is used to obtain the necessary resources because the seeds do not contain enough substances to germinate. Adult plants then switch to mixotrophy or autotrophy, except P. aphylla. Mixotrophy allows pyroloids to combine inorganic carbon gain obtained from photosyntesis and organic carbon from symbiotic fungi. Mixotrophy of this family can significantly affect other plant species growing in its vicinity through mycelial networks of mycorrhizal fungi and contribute to affecting the structure of the community. At the present, all pyroloids are among the endangered or declining species in our country and in the world. This bachelor project summarizes the knowledge about pyroloids in the field of phylogeny, mycorrhizal symbiosis, ecology, distribution and in vitro cultivation in the form of literature research. In the last chapter I deal with the causes of decline and the possibilities of pyroloid protection. Key words: Pyrolaceae, mixotrophy, mycoheterotrophy, ectomycorrhiza, Pyrola, Chimaphila umbellata, Moneses, Orthilia

Initially mycoheterotrophic plants have recently been declining in the wild, even without apparent causes. They are affected by a number of biotic and abiotic factors. The aim of this work is to investigate how selected factors, such as nitrate or symbiotic fungi, may influence their distribution in nature. In particular, the work applies in vitro experiments, molecular determination of fungal symbionts and stable isotope analyses. It describes both the effects of abiotic factor, specifically nitrate, and biotic interactions of initially mycoheterotrophic plants with fungal symbionts. The inhibition of germination by extremely low concentrations of nitrate in asymbiotic in vitro cultures was observed in several orchid species. The degree of sensitivity of each species to nitrate corresponds with the nitrate content of the soil and the nutrient availability requirements of the species according to Ellenberg indicator values. The inhibitory effect of nitrate on orchid germination was also observed in symbiotic in vitro cultures. Out of five tested fungal strains, only one Ceratobasidium was capable of eliminating the inhibitory effect of nitrate. Furthermore, the work reveals that green mixotrophic orchids use photosynthates to nourish the aboveground parts, whereas the belowground parts are...

Mycorrhizal mycelium may form a continuous network (commnon mycorrhizal network - CMN) and connect a number of plants or even entire community in an ecosystem. In the Plant World, CMNs have a number of important physiological and ecological consequences. The present work aims to create a review on current knowledge of CMNs and the associated Wood Wide Web. The next objective is to evaluate the results of individual observations and experiments that have been made on this topic. The introductory chapters 1 and 2 describe the various types of mycorrhizal symbioses (i.e., arbuscular mycorrhiza, orchid mycorrhiza, ectomycorrhiza, ericoid and monotropoid mycorrhiza), their characteristics and ability to create CMNs. The following chapters 3 and 4 describe ecophysiological consequences of common mycorrhizal networks such as maintaining stability of plant populations, invasive plants which exploit CMNs, plant communities and the hypothesis of meta-networks. Mycorrhizal mycelium allows transfer of various substances between two plants. The transferred substances include mineral nutrients (especially nitrogen and phosphorus), but also carbon organic compounds, water, signal substances, etc. The last part summarizes the knowledge on CMN, discusses the advantages and disadvantages of different experimental...