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Hlodavci jako rezervoár hantavirů
KAMIŠ, Jan
This study reveals the presence of hantaviruses in free-living rodents and insectivores in urban areas in the Czech Republic. A large number of hantavirus reservoir hosts were tested for hantavirus RNA in different tissues, using universal and specific primers for amplification of the large and medium fragments of hantavirus genomic RNA. Phylogenetic relationships of obtained nucleotide sequences of hantaviruses were reconstructed. Four different species of hantaviruses were detected, including two species pathogenic (or potentially pathogenic) for humans, suggesting a threat for public health. Additionally, inter-family spillover infections and hantavirus species-associated tissue tropism were recorded in rodent hosts.
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Fungal parasites as a factor affecting the dynamics of microalgal communities
Rosa, Jan ; Šťastný, Jan (advisor) ; Pichrtová, Martina (referee)
This bachelor thesis deals with fungal parasites which are an important factor that affects the dynamics of microalgal communities. Here I sum up the knowledge of parasites especially from Oomycota and Chytridiomycota along with a little focus on other groups. The basic characteristics of these fungal parasites, such as their host specificity and factors that affect their spreading ability between algal hosts, are summarized. The abiotic factors such as light and temperature, which are the most important factors causing epidemic, are mainly discussed. The fungal parasites can change the maximal population size and are able to alter the competitive relationships in microalgal communities. These factors are discussed in individual algal groups. The fungal parasites could be a negative economic player of the bioindustry and their future role in this industry is also discussed. Key words: parasite, host, host specificity, communities dynamics, algae, fungi, phytoplankton
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Host specificity, diversity and distribution of avian malaria parasites in a contact zone of two nightingale species
Šíma, Michal ; Munclinger, Pavel (advisor) ; Sádlová, Jovana (referee)
Avian contact zones were suggested to act as barriers to parasite expansions. I studied haemosporidian parasites (genera Plasmodium, Haemoproteus, and Leucocytozoon) of two Nightingale species which meet in a contact zone in Europe. In total 20 lineages of parasites were detected. Surprisingly, all common lineages were shared by the two host species. The parasite prevalence vary between species (Trush Nightingales were more often parasitized than Common Nightingales.) but did not vary to a large extent within zones inside species Parasitemia of the most frequent Haemoproteus LULU1 lineage assessed by Real-Time PCR method did not differ significantly between the two host species. Six out of nine hybrids of the nightingale species were parasitized. Haemosporidian lineages found in hybrids were also frequent in the parental species. In conclusion, the nightingale contact zone seems to have only little (if any) effect on the distribution of haemosporidian parasites.
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Host specificity of tropical bark and ambrosia beetles (Coleoptera: Curculionidae: Scolytinae, Platypodinae)
HULCR, Jiří
Host specificity of tropical bark and ambrosia beetles was surveyed by rearing the beetles from 13 host trees in a lowland rainforest in Papua New Guinea. Ploeophagous bark beetles show narrow host specificity (usually family-level) typical for herbivorous insects, fungus-growing ambrosia beetles display almost no host fidelity. In both groups of species, the local diversity of plants is unlikely to have played a role in the clade diversification. The ambrosia symbiosis (scolytine beetles and fungi) is shown to be less specific than previously assumed, based on a discovery of new association between Scolytodes unipunctatus (genus of phloem feeders) and three unrelated groups of ambrosia fungi. The hypothesis that apparent polyphagy may conceal specialized populations within a species of a herbivore is tested for Homona mermerodes (Lepidoptera, Tortricidae). The haplotype diversity of the species show no congruence with host plants or geographic origin, confirming polyphagy of the species.
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