National Repository of Grey Literature 19 records found  1 - 10next  jump to record: Search took 0.00 seconds. 
The possibilities of green algae removal from concrete structures
Cochlárová, Milena ; Ptáček, Petr (referee) ; Opravil, Tomáš (advisor)
This master´s thesis deals with the suppression of algal growth on concrete structures. The subject of the work is to design and coatings their own structural concretes containing protective element in order to inhibit the growth of algae. As the coating are tested commercially avaiable and newly created systems. Testing systems are based on the portland cement and chelates of metal (Cu, Ni, Co, Mn, Zn, Al).
There is something in the air: Diversity of lichen symbionts in the aeroplankton
Veselá, Veronika ; Škaloud, Pavel (advisor) ; Vančurová, Lucie (referee)
Lichens that reproduce primarily sexually rely on the presence of their symbionts in the environment. A new lichen cannot develop without direct contact between the filaments of the germinating spore and a compatible symbiotic alga. However, the results of earlier studies do not provide solid evidence for photobiont presence on lichen-colonized substrates. The objective of this thesis was to assess various environmental types (air, bark, soil, stone, and artificial substrates) as potential sources of symbiotic algae. To achieve in-depth understanding of the diversity of green algae at a long-studied Central Bohemian study-site, Illumina MiSeq metabarcoding of the ITS2 rDNA region was combined with traditional sequencing of lichen algal ITS rDNA and morphological observations. The methods used revealed 283 species-level lineages and 1313 OTUs, many of which belonged to unknown species or higher taxonomic categories. All photobiont species associating solely with sexual lichens at the site could also be found in the vicinity of lichen thalli. As a result, both the substrates and the air, where these symbiotic algae occurred as well, may act as photobiont sources. In contrast, many symbionts that associate only with asexual lichen species, were never found at the site outside of lichen thalli....
Coordination of growth and cell cycle progression in green algae
IVANOV, Ivan
Within the past century microalgae have gained importance both as model organisms in cell cycle research and as a biotechnological platform for the production of a variety of economically important compounds. This thesis examines the coordination of growth and cell cycle progression in green algae and attempts to explore the biotechnological relevance of some of the findings. Furthermore, the applicability of confocal Raman microscopy for both quantitative and qualitative analysis of storage biomolecules during the course of the cell cycle of Desmodesmus quadricauda is also investigated. Temperature and light shift experiments showed that there is no direct correlation between growth and cell cycle progression in D. quadricauda. Further analysis revealed that supraoptimal temperature has a profound effect on the cell cycle of Chlamydomonas reinhardtii causing a block in cell division, increase of cell size and over accumulation of starch. Starch production through supraoptimal temperature was successfully demonstrated in pilot scale experiments, however it was estimated that light availability within the culture poses a major limiting factor. Confocal Raman microscopy was successfully applied for the quantitative and qualitative analysis of storage biomolecules including starch, lipids, polyphosphates and guanine.
Systematika zelených kokálních řas tříd Chlorophyceae a Trebouxiophyceae
ŠTENCLOVÁ, Lenka
Aim of the review part is to summarize a current situation in the systematics of the green coccal algae, which were traditionally assembled in only one order: Chlorococcales. Their distribution into the lower taxonomical unites (suborders, families, subfamilies, genera) was based on the classic morphological criteria as shape of the cell and characteristics of the colony. Introduction of molecular methods caused radical changes in our insight to the system of green (not only coccal) algae and green coccal algae were redistributed in two of newly described classes: Chlorophyceae a Trebouxiophyceae. Representatives of individual morphologically delimited families, subfamilies and even genera and species were commonly split in several lineages, often in both of mentioned classes. For the practical part, was chosen two problematical groups of green coccal algae: family Oocystaceae and family Scenedesmaceae - specifically its subfamily Crucigenioideae, which were revised using polyphasic approach. Based on the molecular phylogeny, relevance of some old traditional morphological traits was reevaluated and replaced by newly defined significant characteristics.
Spoil heap toxicity and possibilities for remediation
Venclovská, Lenka ; Frouz, Jan (advisor) ; Lukavský, Jaromír (referee)
The content of this diploma thesis is to verify of possibilities for remediation spoil heap toxicity in Sokolov area, by the help of creating biological crusts. The main question of this work is the possibility of using algae to create biological crust on toxical substrates, which could improve the properties of substrates and contribute to the acceleration of succession. The correctness of this theory was tested using two tests on toxic soils in spoil heaps near Sokolov. In the first test (laboratory test) have been chosen two of the soils and the higher plants, in most cases, even did not germinate. That is why we decided to verify the second option to create biological crust in these phytotoxic soils. Therefore we applied selected kinds of algae in the field, some areas were liming, and the field has been monitoring and sampling during next three years. The results show that the application of dolomitic limestone does not affect progress of biological crusts. The result of the fluorescent microscopy clearly shows, that Klebsormidium algae was the only one of the tested algae, which survived and progressed compact visible crusts.
Auxin transport in algae
Skokan, Roman ; Petrášek, Jan (advisor) ; Bíšová, Kateřina (referee)
Phytohormone auxin plays an important role in regulating plant development. Directional (polar) cell-to-cell auxin transport creates auxin gradients within plant tissues, which trigger a specific developmental response. The vast majority of available data concerns angiosperms. Lower land plants have been much less explored in this regard, but the important auxin-related mechanisms (including polar auxin transport) are already present in mosses. To uncover the origins of auxin action, one must focus on green algae, especially of clade Streptophyta, which are the direct ancestors of all land plants. In this study, the possible effects of auxins, both native and synthetic, were investigated on two algae: basal, unicellular Chlorella lobophora and advanced, filamentous Spirogyra sp. The latter received comparably more attention, since it belongs to a clade now acknowledged as a sister group to land plants. Chlorella lobophora culture growth was irresponsive to synthetic auxin NAA. The average Spirogyra sp. cell length was, however, changed by auxins at high concentrations. By conducting accumulation assays of radioactively labelled auxins and HPLC analysis, auxin metabolism and transport was investigated in Spirogyra sp. This alga was able to metabolize the plant-native IAA, but not synthetic auxins...
Diversity of green algae identified as lichen photobionts
Vaiglová, Zuzana ; Škaloud, Pavel (advisor) ; Štifterová, Anna (referee)
This thesis is focused on green algae, which have been recorded as lichen photobionts. The thesis consists of description of genera from the green algal from classes Ulvophyceae, Trebouxiophyceae and Chlorophyceae. I focused on phylogenetics position of genera, I define their morphology and I summarize their participation in lichen symbiotic relationships. I compare evidences based on the traditional morphological methods and modern molecular data. The following genera can be stated to uncertainly represent lichen photobionts: Trentepohlia, Cephaleuros, Phycopeltis and Dilabifilum from the class Ulvophyceae, and Dictyochloropsis, Chloroidium, Elliptochloris, Coccomyxa, Diplosphaera, Auxenochlorella, Myrmecia, Asterochloris, Trebouxia, Coccobotrys and Leptosira from the class Trebouxiophyceae. The genera Chlorella and Stichococcus are morphologically poorly defined, but they are commonly reported as lichen photobionts. Prasiola associates with the mycobiont, but the identity of their partnership is not certainly defined. The lichen symbiosis of genera Parachloroidium, Pseudochlorella and Gloeocystis has not been confirmed by molecular methods, so far. Key words photobiont, lichen, green algae, Chlorophyta, diversity, phylogeny, Trebouxiophyceae
Comparing the diversity of free-living and symbiotic algae in lichen symbioses
Veselá, Veronika ; Škaloud, Pavel (advisor) ; Vančurová, Lucie (referee)
This work discusses the diversity of free-living lichen photobionts belonging to the class Trebouxiophyceae (Chlorophyta). The introduction summarises the change in perspective on the possibility of existence of free-living photobionts. The main part of this work contains a list of lichen photobiont genera with their description and taxonomical classification. In addition, I summarize published records and of these organisms in studies focusing on diversity of aerophytic and soil algae. The work also contains a list of known lichen photobionts species of the class Trebouxiophyceae. Keywords: Trebouxiophyceae, Trebouxia, green algae, photobiont, lichen, diversity
Dynamika fytoplanktonu kaprových rybníků
SVOBODA, Martin
The bachelor thesis deals with the dynamics of phytoplankton in the short-term time scale and compares it with the annual course of phytoplankton in two studied ponds. In August 2017, samples were taken from two ponds in South Bohemia, specifically from the Dehtář pond and the Kvítkovický pond in 5 respectively three depths. The phytoplankton biomass was determined microscopically. The short-term dynamics of the main phytoplankton groups is contained in graphs. Besides, a list of all designated cyanobacteria and algae species can be found here. The green algae of the genera Crucigenia, Coelastrum, and Oocystis had the highest representation on the Kvítkovice pond. The cyanobacterial concentration was low. The Dehtář pond is dominated by filamentous cyanobacteria of the genera Anabaena and Pseudanabaena, which formed an algal bloom. Chlorococcales dominated the lower water column. In my work, I have not seen diurnal migration of any taxonomic group of algae and cyanobacteria. Microcystis, as a dominant species in the Kvítkovický pond, did not record vertical migration, indicating enough nutrients in these eutrophic ponds. Thus, phytoplankton is apparently not forced to migrate for nutrients to the bottom, and light is a limiting factor in their life cycle in summer.
Dynamics of a lichen symbiosis
Vaiglová, Zuzana ; Škaloud, Pavel (advisor) ; Vondrák, Jan (referee)
The symbiotic relationships often represent not only the permanent cohabitation of two organisms, but they can evolve and change over time. Many papers published so far focused on the the specificity of lichens, characterising both highly specific species and those that can establish a symbiosis with many algal genotypes. In this second case we can imagine the possibility of a photobiont exchange during the life of lichen - the dynamics of lichen symbiosis. In this thesis I compared the occurence and diversity of photobionts within the thalli of lichens growing on the disturbed localities and on the the localities without the disturbance. These two types of localities were similar to species richness of photobionts, but the disturbed localities dominated by the number of photobiont genera. These localities also reached a higher value of phylogenetic diversity. Conversely, non-phylogenetic analysis revealed the higher level of photobiont diversity on non-disturbed localities, where the core of diversity was formed by different lineages of Trebouxia. I have also found the lichens, which cooperate with different algae on disturbed and non-disturbed localities. The photobiont distribution presented in this paper shows the possibility of photobiont exchange during the community succesion. The...

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