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1	Diverzita fotobiontů ve stélkách lišejníků rodu Stereocaulon (Lecanoromycetes, Ascomycota) / Photobiont diversity in the lichen genus Stereocaulon (Lecanoromycetes, Ascomycota) Vančurová, Lucie January 2012 (has links) This thesis is focused on the diversity of lichen photobionts and its relation to the mycobionts and environmental factors. The key objective is to map the diversity of lichen photobionts of the genus Stereocaulon, which has been insufficiently examined in comparison with related lichens Cladonia and Lepraria. In total, 92 samples belonging to 12 species of genus Stereocaulon were examined, being found in four continents, at the altitude of 50 to 2 900 metres a. s. l., and variety of natural and artificial substrata. Phylogenetic analyses were inferred on the basis of ITS rDNA, actin type I, 18S rDNA and rbcL sequences. Photobionts belonging to two unrelated genera within Trebouxiophyceae, Asterochloris and Chloroidium, were found in thalli of Stereocaulon lichens. While Asterochloris represents one of the most frequent photobionts of various lichens, Chloroidium has been until now recorded as a lichen photobiont very rarely. The content of heavy metals in substratum can be considered as a determinative factor for its occurrence. A new lineage affiliated to genus Asterochloris was discovered on the island La Palma (the Canary Islands). Interestingly, none of common, widespread Asterochloris lineages has been found in this locality. The lichen photobionts of the genus Stereocaulon were discovered in 12 of...
2	Biogeografie a specifita fotobiontů rodu Asterochloris / Biogeography and specificity of Asterochloris photobionts Řídká, Tereza January 2012 (has links) This diploma thesis has focused on the diversity and biogeography of Asterochloris photobionts. Since no study so far has been published on the biogeography of symbiotic microorganisms, the presented thesis is the first attemp to trace the biogeographic distribution and endemism of symbionts. By gathering 121 Asterochloris sequences obtained from lichen thalli sampled outside Europe and America, the diversity within the genus increased dramatically. The phylogenetic analysis based on the concatenated alignment of ITS rDNA and actin sequences obtained from Cladonia and Stereocaulon photobionts revealed 28 differently supported clades. Of them, eight lineages were newly discovered. Three environmental factors explaining the best the distribution pattern of Asterochloris photobionts were selected according to the statistical tests of the phylogenetic signal: two different types of biogeographical ecoregions and the substrate type. In general, the genus Asterochloris is distributed cosmopolitally, with a very low rate of endemism. Newly obtained data indicate that the restricted distribution of any photobiont clade is not caused by either historic or biological factors, but more likely by specific climatic or habitat preferences.
3	Diverzita fotobiontů ve stélkách lišejníku Psora decipiens / Photobiont diversity in lichen thallus Psora decipiens Jadrná, Iva January 2017 (has links) Psora decipiens is a characteristic species of the terricolous lichen community Toninio-Psoretum decipientis distributed mostly on calcareous or basic substrates. The community consists in various modifications of lichens Placidium squamulosum, Toninia sedifolia, T. opuntioides, Fulgensia fulgens, F. bracteata and others. Photobionts of the lichen Psora decipiens were determined. Psora decipiens shared with Placidium sp. the single photobiont species, a common terrestrial alga Myrmecia israeliensis. Cloning of ITS rDNA revealed high intrathalline variability in M. israeliensis within a single lichen thallus. Several genotypes were often found in a thallus, uncovering either a high mutation rate of the algae or constant relichenization processes. Saxicolous Psora species (P. testacea, P. himalayana, P. valesiaca and P. rubiformis) had M. biatorellae as a photobiont, indicating a possible photobiont influence on substrate specifity of Psora lichens. Finally, the proper methodology used for identification of lichen photobionts is discussed. For a correct photobiont identification, morphological investigations of intrathaline diversity combined with coherent molecular techniques are needed. Such procedure was not applied in the former studies of Psora decipiens, resulting in a poor characterization of...
4	Dynamika lišejníkové symbiózy / Dynamics of a lichen symbiosis Vaiglová, Zuzana January 2017 (has links) 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...
5	The puzzle of lichen symbiosis : Pieces from Thamnolia Onuț-Brännström, Ioana January 2017 (has links) Symbiosis brought important evolutionary novelties to life on Earth. Lichens, the symbiotic entities formed by fungi, photosynthetic organisms and bacteria, represent an example of a successful adaptation in surviving hostile environments. Yet many aspects of the lichen symbiosis remain unexplored. This thesis aims at bringing insights into lichen biology and the importance of symbiosis in adaptation. I am using as model system a successful colonizer of tundra and alpine environments, the worm lichens Thamnolia, which seem to only reproduce vegetatively through symbiotic propagules. When the genetic architecture of the mating locus of the symbiotic fungal partner was analyzed with genomic and transcriptomic data, a sexual self-incompatible life style was revealed. However, a screen of the mating types ratios across natural populations detected only one of the mating types, suggesting that Thamnolia has no potential for sexual reproduction because of lack of mating partners. Genetic data based on molecular markers revealed the existence of three morphologically cryptic Thamnolia lineages. One lineage had a clear recombination structure and was found in the tundra region of Siberia, shorelines of Scandinavia, and Aleutian Islands. The other lineage was allopatric with the previous, and was highly clonal; only two haplotypes were found across the alpine region of central and southeastern Europe. However, the third lineage was sympatric with the other two, had a worldwide distribution, and although highly clonal, showed a recombinant population structure. Our data could not reveal whether the signs of recombination resulted from rare recombination events due to the extreme low frequency of the other mating type or ancestral variation before the loss of sexual reproduction. However, investigation of Thamnolia’s green algal population showed that in different localities, different algal genotypes were associated with the same fungal genotype. Furthermore, data suggest that Thamnolia carried several algal genotypes within its thalli and shared them with other distantly related but ecologically similar fungal species. Thamnolia lichen symbiosis photobiont mycobiont phylogeography MAT-loci barcoding NGS genome transcriptome Ice Age Natural Sciences Naturvetenskap
6	Erdflechten und ihre Gesellschaften in Nordhessen mit besonderer Berücksichtigung der morphologischen und genetischen Variabilität bei Cladonia furcata (Hudson) Schrader / Terricolous lichens and their communities in North Hessen (Germany) with special emphasis on the morphological and genetical variability of Cladonia furcata (Hudson) Schrader Günzl, Bettina 22 January 2004 (has links) No description available. Mathematics and Computer Science 580 Pflanzen (Botanik) Nordhessen Flechten Erdflechtengesellschaften Rote Liste-Arten Schutzmaßnahmen Cladonia furcata Flechten-Inhaltsstoffe morphologische Variabilität genetische Variabilität ITS rDNA ITS-Varianten Photobiont Asterochloris Mycobiont North Hessen (Germany) lichens terricolous lichen communities Red Data Species protective measures Cladonia furcata chemical variation morphological variability genetical variability ITS rDNA ITS-variants photobiont Asterochloris mycobiont 42.44 42.51 42.48 WWH 000: Flechten, Lichenes {Botanik}

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