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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....
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Let's meet in the littoral: Diversity of symbiosis in the Verrucariaceae lichens
Schmidtová, Jana ; Škaloud, Pavel (advisor) ; Peksa, Ondřej (referee)
Lichens are organisms formed by several symbiotic partners, most importantly a fungus (mycobiont) and an alga or cyanobacteria (photobiont). Although most lichens are terrestrial, some can be found also in aquatic environments. Black crustose lichens from the family Verrucariaceae (Verrucariales, Eurotiomycetes, Ascomycota) were able to adapt to this environment very well and often dominate in the seashore near fluctuating water level. The ability of these lichens to inhabit various environments is associated with their unusually wide range of photobionts. However, this symbiont is not known to most of them. This work investigates the diversity of lichens of the family Verrucariaceae in the littoral zone of the Baltic and the North Sea coasts, the relationships between symbionts and the connection between lichen diversity and the salinity gradient. Using metabarcoding, the diversity of free-living algae in the vicinity of the studied lichens is determined and the symbiotic algae are compared with the photobionts found in the lichens. Mycobionts and photobionts were identified using ITS and 18S rDNA. A total of nine lineages of mycobionts and photobionts were found. The most common lichen turned out to be the species Hydropunctaria maura with its photobiont Pseudendoclonium submarinum. For several...
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Functional traits and functional diversity in lichens
Kolenská, Lucie ; Malíček, Jiří (advisor) ; Vondrák, Jan (referee)
Functional traits are a discussed topic across disciplines and articles with lichens are published as well. Traits are the attributes that define the organism from morphological features through anatomy to the physiology of the individual, including interaction in environmental and environmental influences. The most frequently studied functional trait of lichens is the type of thallus. Another commonly studied trait is the type of photobiont, where the presence of algae Trentepohlia is negatively affected by frost and because of this its number decreases with increasing altitude. Another functional trait of lichens which is studied is reproduction, and also secondary metabolites, which protect lichens, for example, against UV light or herbivores. Functional traits together form functional diversity, which is another way how to measure diversity on a planet where the most diverse ecosystem is not always the one with the highest number of species. Functional diversity indices then can reveal unique communities that should be protected. However, neither the definitions nor the calculation of functional diversity are exatly specified, we use different indices. The Rao index of quadratic entropy is most often used for lichens. Keywords indices, lichenized fungi, mycobiont, photobiont, thallus
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The efect of environmental variables on diversity of lichen photobionts
Červenková, Tereza ; Škaloud, Pavel (advisor) ; Peksa, Ondřej (referee)
Lichens represent a synergistic combination of at least two organisms, a heterotrophic fungus and a photosynthetic alga or a cyanobacterium. This association has resulted in a symbiotic organism, which is well tolerant to environmental influences. In fact, symbiotic relationship provides mutual benefit for both organisms. It is generally well known that the fungal partners of lichens are far less sensitive to environmental conditions, such as the temperature, altitude, rainfall or the type and composition of the substrate, in comparison to their algal partners. Therefore, lichen forming fungi have much wider ecological valences than the photobionts interacting with them. Indeed, most of the photosyntetic genera and species are adapted only to certain environmental conditions. For this reason, the symbiotic algae and cyanobacteria probably play a major role during the initial lichen formation on the site. This thesis focuses on the adaptability of photoautotrophic symbionts of lichens, coccoid green algae and cyanobacteria, to environmental conditions. Ecological diversification of photobionts has a direct impact on their genetic differentiation and thus to differentiate lichen species themselves. Unfortunately, in many studies the authors mostly dealt with the diversity of macroscopic symbiotic...
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Diversity of symbiotic partners within the lichen family Verrucariaceae
Schmidtová, Jana ; Škaloud, Pavel (advisor) ; Steinová, Jana (referee)
This thesis summarizes the current knowledge of photobionts of the lichen family Verrucariaceae. It classifies the free-living photobionts systematically, mentions their main morphological features, distribution, and ecology, and notices their participation in the symbiosis. Subsequently, it also describes and characterizes the fungal component of mycobionts, their phylogenetic position, the main morphological features, distribution, and the most common habitats. Finally, it studies the influence of the environment, mycobiont, and other factors in the occurrence of particular photobionts in lichens. Keywords: Verrucariaceae, photobiont, mycobiont, lichen, diversity, symbiosis, characterization
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Lichen ecology in the relationship to functional diversity and genome size
Konečná, Eliška ; Malíček, Jiří (advisor) ; Palice, Zdeněk (referee)
Eliška Konečná Lichen ecology in the relationship to functional diversity and genome size Abstract This bachelor thesis in its first part summarises and characterizes lichen functional traits and sums up known relation between particular traits and ecological factors of the enviroment. Second part of the thesis focuses on question of genome measurment in general and than summarises known information about lichen genom size. In the second part there is partial focus on relation between genom size and ekology of organisms as well, which could become focus of some study in the future. Key words: functional traits, lichens, mycobiont, genome size
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The efect of environmental variables on diversity of lichen photobionts
Červenková, Tereza ; Škaloud, Pavel (advisor) ; Peksa, Ondřej (referee)
Lichens represent a synergistic combination of at least two organisms, a heterotrophic fungus and a photosynthetic alga or a cyanobacterium. This association has resulted in a symbiotic organism, which is well tolerant to environmental influences. In fact, symbiotic relationship provides mutual benefit for both organisms. It is generally well known that the fungal partners of lichens are far less sensitive to environmental conditions, such as the temperature, altitude, rainfall or the type and composition of the substrate, in comparison to their algal partners. Therefore, lichen forming fungi have much wider ecological valences than the photobionts interacting with them. Indeed, most of the photosyntetic genera and species are adapted only to certain environmental conditions. For this reason, the symbiotic algae and cyanobacteria probably play a major role during the initial lichen formation on the site. This thesis focuses on the adaptability of photoautotrophic symbionts of lichens, coccoid green algae and cyanobacteria, to environmental conditions. Ecological diversification of photobionts has a direct impact on their genetic differentiation and thus to differentiate lichen species themselves. Unfortunately, in many studies the authors mostly dealt with the diversity of macroscopic symbiotic...
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