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Specificity between partners in arbuscular mycorrhizal symbiosis
Voříšková, Alena ; Janoušková, Martina (advisor) ; Püschel, David (referee)
Arbuscular mycorrhiza (AM) is a symbiotic interaction between vascular plants and arbuscular mycorrhizal fungi from phylum Glomeromycota. AM symbiosis is considered as a nonspecific interaction, because AM fungi are able to colonize roots of all plant species which are hosts for this type of symbiosis, nevertheless certain specific interactions exist between the partners. The specificity can be evident on the level of the formation of mycorrhiza, which means that different species of plants can vary in the composition of fungal community in their roots or AM fungi can differ in an ability of colonization and sporulation depending on host plant species. The specificity can also manifest as different functionality of the symbiosis in dependence on the particular partners affecting the mycorrhizal response of the host plants. All of these specific interactions can have an impact on the coexistence and diversity of plants in communities.
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Host specialization and species diversity in Strepsiptera of the genus Stylops
Jůzová, Kateřina ; Straka, Jakub (advisor) ; Malenovský, Igor (referee)
The twisted-wing parasites (Strepsiptera) are entomophagous insect order with cosmopolitan distribution. There are about 600 known species up to date. In spite of this, they have very broad host spectrum. Strepsiptera parasites in seven insect groups (Thysanura, Blattodea, Mantodea, Orthoptera, Hemiptera, Diptera, Hymenoptera). The mutual relationship between genera or even between species are not known, except for the species list and the host specification. Moreover, there is an anambiguous use of their species concept. Some authors consider Strepsiptera as the specialists and they match almost every host species with one separate strepsipteran parasite. The opposite concept is to consider strepsiptera as the generalists. The presence of the crypctic species also affect our understanding of the diversity of Strepsiptera. Therefore, the knowledge of Strepsiptera phylogeny provide us the important information about species diversity of studied group as well as about their coevolution with their hosts. On the basis of molecular analyses of three genes constructed the phylogeny genus Stylops. This genus has the wider spetrum of the host species from other strepsipterans of Stylopidae, It is obvious, that strepsipterans of genus Stylops are mainly specialised on their host subgenus. There was detected two...
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Monoxenous trypanosomatids of invertebrates
Havlová, Jolana ; Votýpka, Jan (advisor) ; Varga, Vladimír (referee)
The class Kinetoplastea contains free-living and parasitic species. One of the most dominant group within the class is the order Trypanosomatida which includes obligate parasites (Trypanosoma, Leishmania) infecting a wide range of hosts. Some species are serious pathogens of humans and domestic animals and cause considerable losses. However, the majority of trypanosomatids belongs to monoxenous parasites of insect which are usually harmless to their hosts. Monoxenous trypanosomatids predominantly infect Hemiptera and Diptera. This diploma thesis is focused on the detection of monoxenous trypanosomatids in cockroaches captured in the Czech Republic and cockroaches from different breedings. Cockroaches are very suitable mechanical vectors of many different pathogens (including parasites) and are significant health threat for humans and animals. First trypanosomatids in cockroaches were documented at the beginning of the 20th century, but there is no study focused on this topic specifically. Another aim of this thesis is morphological and ultramicroscopic analysis and the study of the host specificity of the recently described species Herpetomonas tarakana, isolated from a cockroach. My findings were partly used in the already published study "Diversity of trypanosomatids in cockroaches and the...
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Phylogeny of selected species groups of the genus Torymus (Hymenoptera: Torymidae)
Křížková, Barbora ; Janšta, Petr (advisor) ; Skuhrovec, Jiří (referee)
Chalcid wasps (Chalciodiodea) is superfamily within parasitic group of the order Hymenoptera. These insects attack other arthropods. My thesis is focused on phylogeny of selected species groups of the genus Torymus Dalman 1820, whose range of hosts includes mainly gall-forming insect as gall wasps (Hymenoptera: Cynipidae) and gall midges (Diptera: Cecidomyiidae). Using genes 28D2 rDNA, COI and CytB, I constructed phylogenetic trees, which helped with discussing current view on classification of the genus and with inferring new findings about co-evolution with host organisms. Previously established morphological - ecological species groups were not supported by my analyses in many cases. Morphological traits seem to be convergent for many species. They often do not support observed monophyla as apomorphies. On the other hand, ecology and natural habitat of species was common for many branches in my cladograms. It was found out, that recent hosts are not probably original hosts of the group. Adaptive radiation in different habitats is likely to be the phenomenon that stands behind present-day host range of Torymus species. This process could have occurred after swapping to gall midges and gall wasps. Key words: Chalcidoidea, Torymus, phylogeny, parasitoid, host specifity, co-evolution
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Trypanosomes from the T. theileri group in ungulates in the Czech Republic
Brotánková, Anna ; Brzoňová, Jana (advisor) ; Juránková, Jana (referee)
The Trypanosoma theileri group are blood parasites of ungulates. Confirmed vectors of these protists are horseflies or sheep keds for T. melophagium, but these trypanosomes were also detected in deer keds, mosquitoes and phlebotomus. We targeted on the investigation of possibility mosquitoes acting as vectors and additionally we targeted on the prevalence of T. theileri in mosquitoes at selected locations in the Czech Republic due to previous positive detection there. The measured prevalence has reached 6,4 % in mosquitoes, 4 % in deer keds and 16,7 % in sheep keds. The aim of experimental infections was to discover a potential of mosquitoes and phlebotomus acting as vectors of the T. theileri. Phlebotomus perniciosus and three species of mosquitoes Culex pipiens molestus, Culex pipiens quinquefasciatus and Aedes vexans were used for those experiments. Furthermore, isolates of T. theileri and T. melophagium from different sources were used. The divergence among these isolates and among used species of insect was found. The best results were achieved with Ae. aegypti and isolates from mosquitoes, where prevalence had reached 90,8 %. The infected mosquitoes were used for prediuresis research which had shown infection forms of the trypanosomes in the urine liquid. The phylogenetic analyse of T....
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Diversity of ciliates of the family Nyctotheridae in cockroaches
Soviš, Matyáš ; Čepička, Ivan (advisor) ; Škaloud, Pavel (referee)
Cockroaches are tremendously interesting group of insects with broad morphological diversity and a wide range of lifestyles. They are known to host a plethora of fascinating protists ranging from excavate flagellates through gregarines and amoebozoans to extraordinary ciliates of the group Armophorea. There is however, in contrast to the flagellates, only scarce information on these intestinal ciliates. The available data are mostly only morphological and there is a limited information on their host specificity. Therefore, we chose to inspect the diversity of ciliates in cockroaches, both in the stock cultures of Department of Zoology on Charles University as well as in those collected in nature. We studied their presence in various cockroach lineages, obtained 18S rRNA gene sequence data, and assessed their phylogenetic relationships. We also performed protargol staining of the cells to characterize the morphology of individual lineages.
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Leucocytozoon in passerines
Geržová, Lenka ; Svobodová, Milena (advisor) ; Vinkler, Michal (referee)
Leucocytozoon is the least studied genus of blood parasites of the order Haemosporida comparison with the genera Plasmodium and Haemoproteus. Its transmission is almost exclusively linked with a vector of the genus Simulium, which ensures the circulation of parasites in populations of wild and domestic birds. Numerous species have been are described by classical taxonomy, but it is assumed that this genus hides a number of cryptic species, its diversity being much higer. Methods of detection include microscopy, a classical method used for many decades, and molecular biology methods introducted at the turn of the millenium. Key words: Leucocytozoon, passerines, prevalence, species, dynamics of infection, detection
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Phylogeny of selected species groups of the genus Torymus (Hymenoptera: Torymidae)
Křížková, Barbora
Chalcid wasps (Chalciodiodea) is superfamily within parasitic group of the order Hymenoptera. These insects attack other arthropods. My thesis is focused on phylogeny of selected species groups of the genus Torymus Dalman 1820, whose range of hosts includes mainly gall-forming insect as gall wasps (Hymenoptera: Cynipidae) and gall midges (Diptera: Cecidomyiidae). Using genes 28D2 rDNA, COI and CytB, I constructed phylogenetic trees, which helped with discussing current view on classification of the genus and with inferring new findings about co-evolution with host organisms. Previously established morphological - ecological species groups were not supported by my analyses in many cases. Morphological traits seem to be convergent for many species. They often do not support observed monophyla as apomorphies. On the other hand, ecology and natural habitat of species was common for many branches in my cladograms. It was found out, that recent hosts are not probably original hosts of the group. Adaptive radiation in different habitats is likely to be the phenomenon that stands behind present-day host range of Torymus species. This process could have occurred after swapping to gall midges and gall wasps. Key words: Chalcidoidea, Torymus, phylogeny, parasitoid, host specifity, co-evolution
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Trypanosomes from the T. theileri group in ungulates in the Czech Republic
Brotánková, Anna ; Brzoňová, Jana (advisor) ; Juránková, Jana (referee)
The Trypanosoma theileri group are blood parasites of ungulates. Confirmed vectors of these protists are horseflies or sheep keds for T. melophagium, but these trypanosomes were also detected in deer keds, mosquitoes and phlebotomus. We targeted on the investigation of possibility mosquitoes acting as vectors and additionally we targeted on the prevalence of T. theileri in mosquitoes at selected locations in the Czech Republic due to previous positive detection there. The measured prevalence has reached 6,4 % in mosquitoes, 4 % in deer keds and 16,7 % in sheep keds. The aim of experimental infections was to discover a potential of mosquitoes and phlebotomus acting as vectors of the T. theileri. Phlebotomus perniciosus and three species of mosquitoes Culex pipiens molestus, Culex pipiens quinquefasciatus and Aedes vexans were used for those experiments. Furthermore, isolates of T. theileri and T. melophagium from different sources were used. The divergence among these isolates and among used species of insect was found. The best results were achieved with Ae. aegypti and isolates from mosquitoes, where prevalence had reached 90,8 %. The infected mosquitoes were used for prediuresis research which had shown infection forms of the trypanosomes in the urine liquid. The phylogenetic analyse of T....
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Diversity and host specificity of intestinal protists of cockroaches and termites (Blattodea)
Soviš, Matyáš ; Čepička, Ivan (advisor) ; Kolísko, Martin (referee)
The cockroaches (Blattodea) are morphologically and ecologically diverse group of insects living in manifold habitats. Some of them including many termites (Isoptera) feed on wood in various stages of decay. This is however difficult to metabolise for the vast majority of cockroaches and termites and this is why they harbour in their hindguts symbiotic protists belonging mostly to the excavate lineages Parabasalia and Preaxostyla. In this thesis I sum up the knowledge on the diversity of organisms living in the hindgut of cockroaches and termites and on the host specificity of the most important groups of symbiotic protists. Keywords: Blattodea, Isoptera, hindgut, host specificity, diversity, protist, Parabasalia, Oxymonadida
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