National Repository of Grey Literature 766 records found  1 - 10nextend  jump to record: Search took 0.20 seconds. 


Intraspecific diversity in the ichthyofauna of the Czech Republic, its knowledge and protection
Lusk, Stanislav ; Lusková, Věra
At present, 48 fish and 2 lamprey species occur in the waters of the Czech Republic. Of these, 22 fish species are protected by law all over the country or locally, the protection of 3 fish and 2 lamprey species is conditional. For the time being, there are no legal means to protect their intraspecific (genetic) diversity. In this point, one can only utilise certain indirect measures that follow from the limits pertaining to endangered species. The available knowledge of intraspecific diversity of the fish fauna in the Czech republic is fragmentary an incoherent. That is one of the causes of the absence of legislative means to protect the intraspecific diversity. In addition, the apprehension of this phenomenon by the piscatorial public is insufficient although this diversity is the most endangered by the very fishery management. Increased research and knowledge of the intraspecific diversity of particular species is inevitable as the basis for its conservation.

Monitoring of the influence of indigenous culture of yeasts on the fermentation process of making wine
Michálek, Petr ; Molnárová,, Jana (referee) ; Vránová, Dana (advisor)
This thesis deals with the identification of wine yeasts isolated from the grape must using PCR-RFLP method. The yeasts were isolated from Pinot Noir grape variety must. Grapes were grown and produced in accordance with the requirements placed on organic and integrated farming. Samples were processed in the laboratory, where pure cultures of individual yeast were obtained. A commercial kit was used for yeast DNA isolation. Obtained DNA was used for further analysis. Using the polymerase chain reaction and the primers ITS1 and ITS4 a specific segment of 5.8S rDNA-ITS region was amplified. The PCR products were then detected by electrophoresis in an agarose gel, and after a subsequent purification, three restriction enzymes: HaeIII, HinfI and HhaI were subjected to restriction analysis. The DNA was digested to fragments specific for yeast species and they were detected by agarose electrophoresis. Similarity of these isolates was compared using BioNumerics program and the result is dendrogram of genetic similarity of isolated yeast. The basic chemical analysis of samples must was also performed.

Population structure of flower chafer Oxythyrea funesta (Poda, 1761) and phylogeny of the genus Oxythyrea Mulsant, 1842
Vondráček, Dominik ; Šípek, Petr (advisor) ; Bezděk, Aleš (referee)
Eleven species are distinguished in the genus Oxythyrea Mulsant, 1842 (Coleoptera: Scarabaeidae) nowadays. They are not divided into subspecies. Diversity of the genus is concentrated in the Mediterranean and Oxythyrea funesta (Poda, 1761) inhabit a wide area in the western Palearctic Region. It was observed in last decades, that O. funesta retreated from central Europe to south and then recolonized it back including new areas in northern regions. Master thesis is focused on resolving population structure of O. funesta and partial phylogeny of the genus Oxythyrea using molecular genetic methods. 145 individuals of O. funesta and 15 individuals of five other species of the genus Oxythyrea appear in analysis. We acquired sequences of mitochondrial genes cytochrome oxidase I (807 bp), cytochrome b (381 bp) and nuclear gene internal transcribed spacer 1 (946 bp) from these specimens. The results of phylogenetic analysis confirmed so far the only one existing interpretation of relationships within the genus Oxythyrea based on morphological data. We also confirmed complicated relationships between O. funesta and O. pantherina, which also appear in the historical development of their taxonomy. We detected different genetic lineage in Sicily, southern Italy and Tunisia using phylogenetic trees and haplotype...

Ecology and genetic diversity of Gentiana pannonica populations in different geographical and habitat scales
EKRTOVÁ, Ester
The thesis focused to population ecology and genetics of subalpine species Gentiana pannonica. Pollination ecology of species and generative reproduction in different habitat (primary vs. secondary) were investigated in the field. Genetic variation and structure of G. pannonica populations were studied in three disjunct parts of its distribution range: the Eastern Alps, the Bohemian Forest, and the Giant Mts. Present distribution of G. pannonica in the central past of the Bohemian Forest were processed.

The occurrence of domestic and wild forms of the camels in the old world and their economic use
Burgerová, Michaela ; Gardiánová, Ivana (advisor) ; Jan, Jan (referee)
Genus camel (Camelus) includes two species, the Dromedary camel (Camelus dromedarius) and Bactrian camel (Camelus bactrianus). Camels have a wide range of utilization. People in Arabia countries but also in India and Egypt are using camels as a milk and meat animal, or even as a transport and companion animals and riding animals too. The aim of this thesis was to find sources about camel keeping and using and his role of farm animal in different cultures and countries. And about conditions and requirements in captivity. The first part of thesis contains information about phylogeny and origin of the camel family, taxonomy of camels, short information about the history of domestication and using of camels. There are also described the two species in terms of species biology etc. plus a brief mention of camel hybrids and camel breeds. The second part focuses on the use of camels. The preffered and most common use is in the production of milk, other dairy products from camel milk, fermentation of milk. Another use is for meat performance, meat composition, describes products. His utilization i also useful for other parts such as hair wool and mane, they come mainly from bactrian camel (Camelus bactrianus). The last is working utilization of camels, carrying baggage. Then hobby use. The thesis describes the conditions of keeping camels in captivity, keeping camels in Somalia, requirements for the supply of water and food, housing conditions in the Czech Republic, it is particularly widespread keeping camels in zoos. In Czech Republic they are small private camel breeders. For comparison they are conditions for keeping camels in captivity in Australia.

Microbiota of the digestive tract of bees and related insect and the influencing facftors
Hroncová, Zuzana ; Havlík, Jaroslav (advisor) ; Kalous, Lukáš (referee)
This thesis consists of six research chapters, out of which, five have already been published in research journals, 1 is in the process of submission and the last chapter presents original unpublished confidential data in the process of manuscript preparation. The research presented in this thesis concerns the complex mechanisms of bees and wasps immune system focused on microbiota as component of immunity. As shown in the introduction, highly social and managed species of bees like honey bees and bumble bees, play key roles in natural and agricultural ecosystems worldwide. Recent losses of bees have been attributed to pesticide exposure, poor nutrition, increased parasite loads and habitat degradation. Over the past several years, governments, beekeepers, and the general public worldwide have become concerned by increased losses of honey bee colonies, calling for more research on how to keep colonies healthy. Our main aim was to explore the complex mechanisms of bees and related species gut bacterial populations, their links to insect immunity and investigate the opportunities for an intervention. Part of our aim was to characterise the bumble bee and wasp gut microbiota using 16S RNA sequencing in a search for potentially novel bacterial species. We have tried to explain how microbiome interacts with the host and showed that major members of these communities appear to benefit the host. The simple gut communities of social bees present ideal model systems to investigate the underlying evolutionary and genetic processes of such interactions. Information based on our results may help in the design of proper probiotic supplementation strategies with respect to physiological conditions in the honey bee gut.

Influence of meadow management on the migration behavior of selected species of butterflies
Bubová, Terezie ; Langrová, Iva (advisor) ; Farkač, Jan (referee)
Migrations are the key process and one of the basic biological features, which allow survival of endangered species in fragmented landscape. In the last decades, agriculture intensification, industry and urbanization caused that number of natural butterfly habitats has significantly decreased. The localities originally suitable for butterflies are currnetly converted to farmland or building plots. This PhD thesis aimed to find a compromise solution of meadow management, which should allow a commercial use and concurrently do not jeopardize the continued existence of endangered or threatened species. The main idea of this study was in the intentional emigration causing in the middle of flight period, which should lead into resettlement of the population to another (potentially more suitable) locality. Possibility of aimed manipulation with butterfly emigrations would be considered as a major breakthrough in their protection. The investigated species Phengaris nausithous (Bergsträsser, 1779) and Phengaris teleius (Bergsträsser, 1779) are both considered to be flagship species for protection of European butterflies at open meadows. This study is based on research, which was carried out in 2013-2015 at 17 patch in localities Dolní Labe, Czech Republic. In above mentioned years, one selected meadow was mowed in the middle of flight season and the emigrations were then monitored using mark-release-recapture method. Results of population and migration characteristics were calculated in MARK 8.1 software. Subsequently, the effect of mowing on emigration (comparison of emigrations from the meadow before and after mowing) was evaluated using Statistica 13. The hypotheses of this study were based on the assumption, that the loss of resources after well-timed mowing should increase the activity of adult butterflies. During the monitoring, number of emigrations was increased only in flight season 2015. Unfortunately, the statistical evaluation did not show significant effect of mowing on migrations. On the other hand, the hypothesis dealing with colonization of nearest meadows was confirmed. Effect of intentional emigration caused by management interventions was unfortunately not proved. However, we found out, that even though the population at one mowed meadow decreased clearly, the metapopulation size at the locality remained more or less stable. At investigated (mowed) meadow, there was observed a sharp decline of P. nausithous abundance. On the other hand, P. teleius population was only slightly reduced. It is therefore conceivable, that P. teleius are not as susceptible to innapropriate term of mowing. The results obtained in our research conclusively displayed no possible positive effect of mowing in the middle of flight season and a necessity of suitable management maintenance at localities inhabited by Phengaris butterflies.

Total contents and speciation of arsenic and selenium in plants growing in soils with different physico-chemical properties
Tremlová, Jana ; Száková, Jiřina (advisor) ; Vymazal, Jan (referee)
This dissertation thesis deals with uptake, accumulation and transformation of arsenic and selenium in plants growing on soils with different chemico-physical soil properties. The contents of arsenic were investigated in 99 wild plant species, coming from 27 different families and 6 different vegetables growing in arsenic contaminated soils. The results suggest that there are species-specific mechanisms which protects certain plants from the excessive uptake of arsenic from the soil. On the other hand, there are plants using a strategy of accumulation, which theoretically may increase the risk of arsenic entry into the food chain, whether through grazing cattle and wildlife or through consumption of vegetables growing on arsenic contaminated soils. The most prevalent arsenic compounds are AsV and AsIII. Other arsenic compounds occure as minor species. An important finding was detection of arsenobetaine in Plantago lanceolata L. and Carex praecox Schreb .. The contents of selenium were examined in 73 species of wild plants, coming from 29 different families. The results suggest that naturally low levels of selenium in the soil of selected locations along with a low capability of selenium uptake via collected plant species lead to the low content of selenium in plant biomass which may contribute to selenium deficient throughout the food chain. Foliar application of selenate on wild plant communities and on some types of vegetables in our case Brassica oleracea var. italica can have a positive impact on increasing the selenium content in the aboveground biomass of these plants and by extension, increase the selenium content in the human diet. Dominant selenium compounds in the aboveground biomass of the analyzed plants were SeVI and selenomethionine, with variable proportion of other commonly occurring organic selenium compounds, which is mainly affected by plant species.

Arsenic speciation by hydride generation coupled with atomic fluorescence spectrometry
Marschner, Karel ; Musil, Stanislav ; Rychlovský, P. ; Dědina, Jiří
Post-column hydride generation for arsenic speciation was used and the demethylation of Arsenic species during hydride generation was investigated.