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How to become a critically endangered species: a review of the distribution and status of the crucian carp (Carassius carassius)
Janda, Benedikt ; Choleva, Lukáš (advisor) ; Lojkásek, Bohumír (referee)
The Crucian carp (Carassius carassius) is the native species of fish in European standing and slowly flowing waters. Thanks to their high resistance to adverse abiotic conditions, they also inhabited dead arms of river, ponds and floodplains. Despite its resilience, this species has been declining or completely retreating from the most of natural habitats since the middle of the 20th century. The negative direct human interventions into the species populations were, intensive fishing and the elimination of suitable habitats as a result of landscape defragmentation, which was part of flood control measures. Secondly, the human-made introductions of non-native species, the Gibel carp (Carassius gibelio), capable of gynogenetic reproduction, strongly competes with the native species for resources. The extent to which the situation of the native Cruvian carp is critical and ow it has historically occured is revised in the formo f literaly search by this bachelor's Thesis. Keywords The Crucian carp, gynogenesis, molecular genetic methods, cytochrome b gene, taxonomy, hybridization, introduction, microsatellites
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The controversial nature of a social enterprise as a commercialized organization of the civil sector
Hořínková, Monika ; Frič, Pavol (advisor) ; Witz, Petr (referee)
The topic of this diploma thesis is the commercialization of civic organizations, which we understand as the process in which they take over some procedures, methods and strategies of the commercial sector in order to generate some profit. As the highest level of commercialization, this work considers the transformation of civil organization into a so called social enterprise.At the next potential level, this civic organization would become a pure market enterprise acting as socially responsible. Thus, a social enterprise is defined as a civic organization, for which profiting is just as important as an increase in public benefit by fulfilling of its own altruistic mission. However, it is said that this social mission may be threatened by the economic one. Whereas the social enterprise combines those two opposing attributes in the form of a social and economic mission, it is considered to be controversial. That's why the aim of this diploma thesis is to determine the importance of a transformation of civic organization into the social enterprise for its life and how this transformation affects its functioning and its essence. The diploma theses is based primarily on the theory of civil society, the civil sector, the social economy and the theory of social enterprise. It is a case study, which...
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Invasion of Phytophthora alni in Europe
Pecka, Štěpán ; Černý, Karel (advisor) ; Kolařík, Miroslav (referee)
Species complex Phytophthora alni s. l. (Peronosporomycetes: Stramenopila) is a group of invasive pathogens of alder trees. It spreads mainly via water and causes root and collar rot often resulting in the death of attacked trees. Especially in riparian stands it often causes significant losses of alder and therefore remarcable changes of ecosystems and watercourses. The species complex is very polymorphic and divided into three species - P. ×alni, P. uniformis and P. ×multiformis. The most widespread in Europe and in the Czech Republic is the P. ×alni species. The aim of this thesis is to summarize information about P. alni complex (and especially of the most important taxon P. ×alni), to describe history of its spread and development of its area in Europe, genetic variability and inner structure of its populations, ecology and pathways of spread and, based of the known results, decribe the current situation of the invasion. Key words: Phytophthora alni, Peronosporomycetes, Alnus, pathogen, hybridization, area, riparian stands
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An assessment of interspecific hybridization between Central-European taxa from the genus Nymphaea: insights from flow cytometry and multivariate morphometrics
Kabátová, Klára ; Suda, Jan (advisor) ; Rybka, Vlastimil (referee)
Although the genus Nymphaea (waterlily) includes only two native species (N. alba and N. candida) in Central Europe, it poses a great challenge to taxonomy and biosystematics. The determination of both species is hampered by their phenotypic similarities, and species boundaries can be further blurred by interspecific hybridization. In addition, ornamental cultivars of different parentage often escape from cultivation and make the situation even more complex. To get insight into the caryological and phenotypic variability of czech waterlilies, the DNA flow cytometry and both distance-based and geometric morphometrics were used. Collections showed two different groups of fluorescence intensities, corresponding to N. alba and N. candida, respectively. In addition, intermediate values of nuclear DNA amount were found in some plants from South Bohemia, indicating their hybrid origin. Surprisingly, ornamental cultivars possessed the smallest genome sizes. The amount of nuclear DNA therefore seems to be a promising species-specific marker that enables not only native species but also cultivars to be distinguished. Cytometrically-proven individuals have been subjected to multivariate morphometrics, and high differenciation was discovered especially between native species. More complicated seems the distinction...
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Application of next-generation sequencing for phylogenetic reconstruction of polyploid plants
Skopalíková, Jana ; Fér, Tomáš (advisor) ; Šrámková, Gabriela (referee)
This bachelor thesis summarizes available information about currently used next- generation sequencing (NGS) methods where a big progress was achieved during last few years. Great advantage of NGS is the ability to gain huge amount of data at much lower cost per base compared to the Sanger sequencing. However, there are various pitfalls in data analysis. Nowadays it is possible to sequence the entire genomes of individuals. Nevertheless, this approach remains challenging when studying many individuals, e.g. in phylogenetics. Recently, several approaches for effective reduction of genome complexity arose: transcriptome sequencing (RNA-Seq), target enrichment, restriction digest-based methods (RAD-Seq, RLL, GBS), genome skimming (shallow sequencing), etc. Each method has both advantages and disadvantages that affect its utility in phylogenetics. Furthermore, the thesis deals with polyploid speciation and particularity of phylogenetics in polyploid plants - selection of suitable markers followed by data processing and phylogenetic analyzes. The last part of the thesis is devoted to my future research of polyploid genus Curcuma L.
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Mechanisms of asexual reproduction in reptiles
Augstenová, Barbora ; Kratochvíl, Lukáš (advisor) ; Abramjan, Andran (referee)
In the case of reptiles, there has been described an occurrence of an asexual reproduction, especially in the case of a group Squamata; the asexual reproduction of birds (Aves) has been observed, too. Multiple times the asexuality of reptiles has been originated. Occurrences of obligate and facultative asexual species have been described. Most obligate asexual species have theirs origin in one or more hybridization events between closely related species. However, within the family Xantusiidae two exceptions where asexuality apparently originated without hybridization were discovered. Facultative parthenogenesis was originally expected only among reptiles kept in captivity, where the females were separated from males for a long time. However, this assumption was later disproved. The majority of the specimens formed by facultative parthenogenesis has reduced viability, which can be caused by the imperfect mechanism of the formation of parthenogenetic offspring. The terminal fusion is considered to be the probable mechanism of creation of diploid oocytes in the case of facultative parthenogenesis reptiles. The cytological mechanism of the parthenogenetic offspring's genesis was described for the obligate parthenogenetic species just for genus Aspidoscelis. During oogenesis in this case is ploidy...
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Hybridization of crab apple with domestic apple trees
Portl, Jiří ; Fér, Tomáš (advisor) ; Prančl, Jan (referee)
This bachelor thesis summarizes known information about hybridization (anthropohybridization) crab apple with orchard apple. Next it follows up mainly genetic and morphometric methods that haven't been used in the hybridization studies yet. Crab apple (Malus sylvestris) is the only one wild species in Malus genus in Europe. However in the last few decades these populations are endangered by orchard apple (Malus ×domestica), that originates from central Asia. It often outspreads into the free nature and thereby closer to wild apple plants, that leads to easier hybridization of these two woods. This process leads up to decreasing number of genetically pure crab apple individuals and also to slow hybrid plants expansion. This trend, which was called anthropohybridization, can be observed also in the Prunus genus, where there hybridizes wild species European dwarf cherry Prunus fruticosa with tart cherry Prunus cerasus. Recent studies though refers to following genetic aspects of Malus domestica, namely formation by triple hybridisation. Several locations of crab apple were observed and analysed in Europe in the last few years for study of anthropohybridization degree with Malus ×domestica. There were observed hybrid plants in common with genetically pure Malus sylvestris. Key words: crab apple,...
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Evolutionary history of tetraploid representatives Galium pusillum group (sect. Leptogalium) in central Europe. Allopatric differentiation of Czech endemic species G. sudeticum
Knotek, Adam ; Kolář, Filip (advisor) ; Chrtek, Jindřich (referee)
The presented study tries to reveal the evolutionary history of polyploid complex Galium pusillum aiming on a rare czech endemic species G. sudeticum, an ideal model to study allopatric speciation in the context of Central European (post)glacial development. The species G. sudeticum grows in Krkonose Mts. and on serpentines in western Bohemia (Slavkovský les) more than 200 kilometers away. Our morphological and molecular data suggest a clearly different history of its two isolated areas. The populations in Krkonose Mts. are probable relics of mountainous species G. anisophyllon which was there on its northern border of occurence and hybridized with lowland species G. valdepilosum during postglacial vegetations shifts. This fact is well supported by intermediate position of Krkonose Mts. populations in both morphological and molecular AFLP analyses and by sharing the same chloroplast haplotype with geographically close lowland populations. On the other hand the serpentine lowland populations in western Bohemia are both morphologicaly and genetically indistinguishable from G. valdepilosum. Distinct genetic lineage of few populations belonging to G. valdepilosum (incl. one traditionaly referred as G. sudeticum) was found in western Bohemia and Bavaria, located on relic stands (calcareous and serpentine...
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