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The influence of roots on the chemical properties of the apoplast and the rhizosphere
Puldová, Kristýna ; Fendrych, Matyáš (advisor) ; Šámalová, Markéta (referee)
Chemical properties of the apoplast and rhizosphere are crucial for plant development and its overall well-being. Apoplast includes space outside the plasma membrane and its content, such as gas, water, and solutes. Changes in apoplast properties significantly influence various processes. One of them is cellular growth - the pH-dependent extension of cell walls. The rhizosphere is the soil environment near and under the influence of roots. It is characterised by abiotic factors like the availability of nutrients and toxic compounds. It is also a space with a high representation of microbiome communities. Plants can significantly influence the chemical properties of both apoplast and rhizosphere to improve their growth conditions. This thesis summarises the most important mechanisms of plants' roots that change these chemical properties, focusing on the model plant Arabidopsis thaliana. It shows how and where these mechanisms intersect and in which way they influence each other. Emphasis is placed on the process of growth regulation and mechanisms of increasing nutrient availability. Keywords: apoplast, rhizosphere, H+ ATPase, root growth, rhizodeposition, root exudates, nutrients, microbiome
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Effect of long-term drought on plant-associated microbiota
Billichová, Tereza ; Münzbergová, Zuzana (advisor) ; Kohout, Petr (referee)
Plant-associated microorganisms are very important for plant growth. Microbiota influence, for example, nutrient uptake, flower and fruit production or biocontrol of pathogens. Microorganisms are found in various plant organs. Each plant part then creates different environments for the microorganisms to live in. This may influence their different functions depending on which plant part they are found in. One such function is to help plants cope with adverse conditions. Drought, as an adverse condition, has a major effect on both plants and micro-organisms. The aim of this thesis is to study effect of long-term drought on the composition of the microbiota in the rhizosphere and leaf and root endosphere. Long-term drought affected the composition of microbial communities in different plant parts. According to the original hypothesis, the response to drought of prokaryotes differed from that of fungal communities. Fungal communities are more stable and their alpha diversity did not change much during the different durations. The opposite trend in diversity is seen in prokaryotes, where a relative increase in specialists can also be observed. Regarding specific microbial taxa, the results confirm the previously reported trend of increasing Actinobacteria abundance during drought. For fungi, on the...
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The role of plant root exudates for soil carbon sequestration
Bourdais, Lukáš ; Albrechtová, Jana (advisor) ; Tylová, Edita (referee)
Global climate change is a process that affects us all today and will continue to affect us with increasing intensity in the future. An important way to reduce the concentration of CO2 in the atmosphere is the sequestration of carbon in pools other than the atmosphere, primarily in the soil pool. One way to achieve this is by increasing the carbon sequestration into the soil biomass using root exudates. Root exudates are released by plant roots into the soil to be beneficial to the plant and are also a good source of carbon for the rhizosphere (the soil in the immediate vicinity of the root system affected by its exudates). The rhizosphere is thus a suitable environment for microorganisms that play a major role in the soil carbon sequestration. In this thesis, I describe the composition and the role of root exudates for the plant, the importance of root border cells and border-like cells, the importance of exuded carbon coumpounds for microorganisms in the soil and their importance for carbon sequestration and CO2 mineralization in the soil. The role of root exudates and microorganisms in the soil carbon cycle is discussed with an emphasis on mineral-associated soil organic carbon and soil aggregates. This thesis also discusses the role of exudates for the rhizosphere priming effect and its...
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Rhizobiom pro zvýšení resilience polních plodin ke změně klimatu
Řezáč, Vlastislav
The bachelor thesis focuses on the importance of the plant root system and associated symbiotic microorganisms. The aim was to describe these relationships, present their advantages in agriculture and methods of their adoption. In the practical part, the root system was evaluated using WinRHIZO software. The material used was the grown root systems of Trifolium sp. plants at the age of 18 days. The basic parameters associated with the root system characteristics, i.e. total length, total surface, average diameter, total volume, number of tips, number of branches were determined. The number of formed nodules was also determined. As a secondary result, the macrophenological phase of the initiation of nodule for-mation was determined between BBCH 10 and BBCH 11.
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Rozdílné mikrobiální aktivity v rhizosféře trav Festuca ovina a Calamagrostis epigejos
Filipová, Lenka
The diploma thesis "Different microbial activity in the rhizosphere of grasses Festuca ovina and Calamagrostis epigejos" deals with the issue of climate change and eutrophication and their impact on the stability of rare habitats, specifically dry acidophilous grasslands in the Podyjí national park. The aim of the thesis is to study and collect the available sources about the issue of the interaction of soil microorganisms and plant roots in exceptional and protected dry grassland ecosystems, which are colonized by aggressive expansion of Calamagrostis epigejos, thereby compromising their integrity and stability. This issue is still not fully understood. Review of literature in the thesis describes the explanation of the most significant part of the issue - the nutrient cycling in ecosystems, C: N ratio, the role of microorganisms in the soil, and the importance of microbial processes in the rhizosphere and in grassland ecosystems generally. In the experimental part the hypothesis - that drought stress and eutrophication causes changes in the plant - microorganisms - soil system, which result in destabilization of the system, by an increase in leakage of nitrate and ammonium ions from the soil, and in changes in the quantity and quality of underground and aboveground biomass of Festuca ovina -- was confirmed.
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Vliv rostlin s různou ekonomickou strategií na půdní procesy
ŠKOPOVÁ, Kateřina
This bachelor thesis addresses plant-soil interactions through plant litter and living roots, compares the effects of plants with a competitive and conservative resource management strategy on soil and ecosystem functioning. The literature review is followed by a proposal for a scientific project aimed at increasing knowledge of the rhizosphere processes of competitive and conservative species and testing the validity of the hypothesis that competitive species affect their environment more intensively than conservative species.
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Fungi associated with tree roots
Charvátová, Markéta ; Baldrian, Petr (advisor) ; Gryndler, Milan (referee)
In contrast to the bulk soil environment, plant roots represent a habitat with higher nutrient availability due to the supply of photosynthesis-derived C-containing compounds. The roots thus support the life of various microorganisms that use such compounds, but the root-associated microbes in the same time may face a limitation in N and P availability. Unlike bacteria, many filamentous fungi are able to transport these compounds from soil and their mycelia thus typically extend into this environment. Ectomycorrhizal fungi are a typical example of this nutrition strategy. Tree roots produce exudates, that differ in thein composition for each species and they can also differ among individuals. It causes a high diversity of root-associated fungi. Soil is also inhabited by parasitic and saprotrophic fungi. Composition and activity of microbial communisies in the rhizosphere differ from the bulk soil. This work points at the differences of the rhizosphere and builk soil, the importance mycorrhizal fungi and it presents an overview of fungal species that have been found on the roots of spruce - Picea abies. Key words: fungi, mycorrhiza, soil, rhizosphere, Picea abies
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Interactions of macrofungi and trace elements in soils
Cejpková, Jaroslava
This PhD thesis follows my master's thesis, which I focused on the problem of uranium determination and content in macrofungal fruit-bodies (the results have been published, Appendix 1). Macrofungi apparently do not accumulate uranium in fruit-bodies but as other studies suggested major roles of fungi in environmental geochemistry of uranium, I hypothesized possible accumulation of uranium and other elements in ectomycorrhizae. I therefore decided to continue the research and focus on investigation of trace elements in ectomycorrhizae. As I had opportunity to use a variety of analytical methods, I also participated in other studies in the field geomycology and the results are included in this thesis. In response to alarmist reports in Czech media, I focused on activity and distribution of radiocaesium in fruit-bodies of Boletus badius. As demonstrated in Appendix 2, the fruit- bodies of this species do not represent a health risk for mushroom consumers. Distribution of mycelium of saprotrophic Agaricus bernardii in a soil profile in Prague was investigated by use of molecular methods (PCR with specific primers). The results have shown that the mycelium reaches the depth of 30 cm. Lead isotopic composition of fruit- bodies suggests lead can be accumulated from soil depth of 13-17 cm (Appendix 3)....
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