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Interactions among free-living prokaryotes and protists in microbial communities
Jirouchová, Kateřina ; Pánek, Tomáš (advisor) ; Fiala, Ivan (referee)
Protists and prokaryotes live in the natural environment in complex microbial communities whose members interact with each other. These communities consist of a few to many species that interact with each other in many ways such as predation/prey, ecto/endosymbiosis, parasitism, modulation of development or behaviour and harmful algicidal/bactericidal interactions, resulting in a complex network of interactions that influence structure of the microbial community as well as metabolism and behaviour of present species. This bachelor thesis is an overview of the interactions between free-living protists and prokaryotes within microbial communities, excluding well-studied interactions such as predation, parasitism, and ecto/endosymbiosis, while focusing on the diversity of lesser- known interactions, highlighting their importance and future research opportunities.
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Soil microbial communities in agroecosystems and natural habitats contributing to resistance and resilience of the soil environment
Sarikhani, Ensyeh ; Kopecký, Jan (advisor) ; Demnerová, Kateřina (referee) ; Větrovský, Tomáš (referee)
Ensyeh Sarikhani Soil microbial communities in agroecosystems and natural habitats contributing to resistance and resilience of the soil environment. Summary The control of common scab of potatoes (CS) includes resistant varieties (cultivars), precise fertilization, increase of soil moisture, and chemical treatments. Yet, these management practices do not have common or reproducible results at differing sites. A monitoring study was done in 32 sites to evaluate the relation between CS and biological/chemical soil parameters. Correlations were observed between scab severity and content of nutrients such as Fe, N, and Ca in soil and periderm, and between disease severity and abundance of actinobacteria and total bacteria, together with the pathogenicity determinant, txtB gene (biosynthetic gene of thaxtomin) in both soil and periderm of potatoes. The findings led to novel conclusions, which can help to understand relationships applicable in scab control. Peat and DTPA chelated iron were supplemented to pots filled with soil conducive for CS in order to determine the effects of soil organic matter, iron and pH on CS development. The results were compared with data obtained for a suppressive soil from a nearby field with naturally low CS severity. Both peat and iron supplements decreased CS and the combination...
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Microbial community in sediments of a stream contaminated by pharmaceuticals
Brťková, Hana ; Cajthaml, Tomáš (advisor) ; Zikánová, Blanka (referee)
Pharmaceuticals are micropollutants, that enter the environment mainly through Wastewater Treatment Plants (WWTPs). In this work microbial community has been studied in sediments of a stream, which is located near a WWTP. This sediment is contaminated with pharmaceuticals. The subject of this thesis was to determine the presence of pharmaceuticals and microbial community in this study site and to point out possible relationships between these factors. Twelve pharmaceuticals were identified at concentrations reaching levels of ng/g. The concentrations of the compounds form a gradient that decreases with the distance from WWTP. Microbial biomass was estimated using the analysis of phospholipid fatty acids and microbial community was described using next-generation DNA sequencing. The analysis of phospholipid fatty acids pointed out, that with the increasing distance from WWTP the amount of microbial biomass decreases. DNA sequencing revealed large microbial diversity in the studied sediment. For evaluation of the relationship between the microbial community and pharmaceuticals in the stream sediment, Principal Component Analysis (PCA) was used. The result of PCA showed, that in the stream sediment (depth 10-30 cm), Betaproteobacteria negatively correlated with triclosan and Clostridia negatively...
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Soil microbial communities in agroecosystems and natural habitats contributing to resistance and resilience of the soil environment
Sarikhani, Ensyeh ; Kopecký, Jan (advisor) ; Demnerová, Kateřina (referee) ; Větrovský, Tomáš (referee)
Ensyeh Sarikhani Soil microbial communities in agroecosystems and natural habitats contributing to resistance and resilience of the soil environment. Summary The control of common scab of potatoes (CS) includes resistant varieties (cultivars), precise fertilization, increase of soil moisture, and chemical treatments. Yet, these management practices do not have common or reproducible results at differing sites. A monitoring study was done in 32 sites to evaluate the relation between CS and biological/chemical soil parameters. Correlations were observed between scab severity and content of nutrients such as Fe, N, and Ca in soil and periderm, and between disease severity and abundance of actinobacteria and total bacteria, together with the pathogenicity determinant, txtB gene (biosynthetic gene of thaxtomin) in both soil and periderm of potatoes. The findings led to novel conclusions, which can help to understand relationships applicable in scab control. Peat and DTPA chelated iron were supplemented to pots filled with soil conducive for CS in order to determine the effects of soil organic matter, iron and pH on CS development. The results were compared with data obtained for a suppressive soil from a nearby field with naturally low CS severity. Both peat and iron supplements decreased CS and the combination...
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Importance of fungal decomposition of wood in the ecosystems of natural forests
Štercová, Lucie ; Baldrian, Petr (advisor) ; Kolařík, Miroslav (referee)
The decomposition of organic substrates represents an important part of the global carbon cycle and affects its global change through CO2 release. In temperate forests, deadwood represents a large carbon stock, its amount and decomposition is crucial for ecosystem biodiversity and functioning. The fungi are omnipresent powerful decayers in all terrestrial ecosystems. Their ability to decompose all deadwood compounds, mainly lignocellulose, is highly important. Without fungi, the wood decompositions and the release of withheld nutrients back to nutrient cycles couldn't be performed. While many studies were concerned with the estimation of decomposition rates of deadwood, still deeper knowledge about microbial decomposition processes and the diversity of saproxylic species and their interaction is needed. The fungi are still underrepresented in dead wood studies. This study had two main objectives. First was to describe the fungal community on downed deadwood of Fagus sylvatica and Abies alba in natural forest of Salajka in the Czech Republic, to reflect the substrate changes during the different decay stages, and to link the enzyme activities to fungal community composition and their described ecophysiologies. Second aim was to describe the fungal communities on standing and downed dead logs of...
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Effect of agronomic and nutritional measures on soil biological activity
KINCL, Petr
This bachelor thesis is a literature review, examinig the effect of agricultural and nutritional measures on soil biological activity. Bachelor thesis is systematically divided into several parts. At the beginning of the thesis are included important dates regarding soil organic matter and edaphon. Another part of the work has been to study effects of fertilization and liming on soil biological activity. Furthermore, there are studies on the impact of agro-technical measures and the impact of the application of pesticides. The paper also lists methods of research soil biological activity.
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Biodegradability of dissolved organic matter in soils of spruce swamp forests
ŽAMPACH, Ondřej
The aim of this thesis was to assess the biodegradability of dissolved organic matter in spruce swamp forest in habitats differing in dominant vegetation and water table. Sampling was conducted on three study sites located in Šumava National Park in the Czech Republic. Main hypothesis was that the presence of different dominants can modify the overall DOM quality and biodegradability.
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Hunters or gardeners? Plant-microbe interactions in rootless carnivorous Utricularia
SIROVÁ, Dagmara
Various aspects of the ecophysiology of rootless carnivorous Utricularia plants were assessed, with focus on nutrient acquisition and mutualistic interactions within trapping organs. The study includes extracellular enzyme measurements, the evaluation of commensal microbial community structure and function, stable isotope labelling to determine plant carbon allocation, and ion chromatography analyses of trap fluid composition
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