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The importance of polyploidization in the evolution of grasses of the tribe Triticeae
Papoušek, Lukáš ; Urfus, Tomáš (advisor) ; Chrtek, Jindřich (referee)
Polyploidization, as a process of chromosome set multiplication, represents one of the most significant forces that shaped the evolution of angiosperms. Therefore, understanding the mechanisms of polyploidization is also important. It most often originates through unreduced gametes (less so through somatic polyploidization). Autopolyploids are the result of polyploidization within one species, or population, while the formation of allopolyploids is preceded by interspecific hybridization. Polyploidization also played a major role in the tribe Triticeae (Poaceae), which includes economically significant crops (wheat, rye, and barley). The taxonomy ofthe entire tribe, especially the generic concept, has been based on genomic concepts in recent decades. However, taxonomy is considerably complicated, particularly due to hybridization, or allopolyploidization. The result of allopolyploidization and even hybridization itself is a reticulate pattern, and it is not at all easy to determine the boundaries between taxa, even at the generic level. Triticum aestivum can be considered a model species for the study of allopolyploidy, both due to its economic significance and its origin through several rounds of hybridization events. Although allopolyploidy prevails, autopolyploidy can be encountered to a lesser...
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Polyploidization and hybridization as evolutionary drivers in the Medicago sativa group
Peřina, Ondřej ; Kolář, Filip (advisor) ; Bartolić, Paolo (referee)
This bachelor's thesis addresses polyploidy induced by whole genome duplication and its consequences to the evolution of Medicago sativa species complex, i.e. wild relatives of an important forage crop alfalfa. This complex encompasses several interfertile taxa naturally occurring as diploid (2n = 16) or tetraploid (2n = 32) cytotype. Several recently conducted studies attempted to explain origin and evolution of this complex and relationships among its members using modern molecular methods, however, the results are still fragmentary and inconclusive. Two most widespread members of the complex: purple flowering Medicago sativa and yellow flowering Medicago falcata are genetically differentiated both at diploid and tetraploid level, what is supporting their recognition as distinct taxa. Furthermore, it has been shown that tetraploid M. sativa subsp. sativa is an autopolyploid that originated from diploid M. sativa subsp. caerulea by intraspecific whole genome duplication. On the other hand, the origin of tetraploid M. falcata seems to be more complex, presumably involving autopolyploidization followed by past introgression from Medicago prostrata. Most of the studies concerning this topic were performed on accessions, which are sometimes of uncertain ploidy and origin, obtained from germplasm...
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Genome duplication in Stellaria genus - the more, the merrier? Link between ploidy levels and sexual polymorphism.
Krtilová, Eliška ; Slovák, Marek (advisor) ; Prančl, Jan (referee)
Polyploidization in angiosperms, a well-documented phenomenon, often correlates with a diversity of reproductive strategies, including sexual polymorphism, impacting their evolution and expression. This relationship is particularly intriguing in high polyploids, where the interaction can be complex yet largely enigmatic. We investigated the connection between high polyploidy and sexual polymorphism in Stellaria palustris (Caryophylaceae), a species complex with exceptionally high levels of polyploidy exceeding decaploids and reportedly exhibiting variable sexual expression. To broaden our analysis, we included its relatives, diploid-tetraploid S. graminea and diploid S. longifolia. Our study focused on Central and Northern Europe, utilizing various methodological approaches, including genome size estimation, chromosome counting, genetic analyses based on Sanger sequencing, and evaluating floral organ variability and sexual expression. Major hypotheses examined associations between ploidy level and latitude, as well as ploidy level and sexual polymorphisms. Chromosome counts of S. palustris ranged from 2x = 154 - 208, corresponding to 2n=12x, 14x, and 16x, while for S. graminea and S. longifolia, we confirmed their originally known ploidies. Although chromosome counts did not unambiguously reflect...
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Alternative powertrains of vehicles
Filip, Vojtěch ; Kučera, Pavel (referee) ; Píštěk, Václav (advisor)
The aim of this thesis is the analysis of most common alternative drive systems currently used in cars, their comparison with the current gasoline and diesel engines. Familiarization with the technical solutions of drives, their categorization into several groups according to the specific key features. It also deals the most important components of an alternative fuels automobiles, respecting their strengths and also weaknesses that currently hinder expansion of these propulsions, economically as well as technically.
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Modern hybrid drive of passenger vehicles
Švoma, Jan ; Blaťák, Ondřej (referee) ; Vančura, Jan (advisor)
This bachelor thesis deals with the current hybrid-drives in passenger cars. The thesis contains the categorization of hybrid systems according to structure and use. It also discusses the analysis of individual components and describes their suitability for use in different situations. It is focused on current offering of hybrid vehicles and development opportunities. At the end of are evaluated economic aspects and prospects for the use of these systems in the future.
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Post - conceptual Approaches in the Contemporary Czech Painting
Dub, Petr ; David,, Jiří (referee) ; Havlík, Vladimír (referee) ; Zálešák, Jan (referee) ; Stratil, Václav (advisor)
The dissertation thesis entitled Selected Post-conceptual Approaches in the Contemporary Czech Painting reflects the author’s expressions of the youngest artists’ generation working with the conceptual forms in the painting medium after 1996. The aim of the dissertation is to outline the conflict and overlapping of the conceptualism and painting. Apart from the development of conceptual art, the reference framework of the submitted thesis also comprises the post-modern turn in visual arts associated with a global change in its social status during the second half of the 20th and at the beginning of 21st century. The development of the domestic artistic scene and particular approaches are presented on the basis of a representative selection of the most distinctive tendencies and significant authors, being compared with the work of foreign artists. The text interprets the key theoretical treatises, reviewed responses and artists’ statements covering the domain of “contemporary painting to conceptual art”.
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Living in Intensive Urban Structures
Zadražilová, Miroslava ; Urbášková, Hana (referee) ; Šimeček, Pavel (referee) ; Vitková, Lubica (referee) ; Menšíková, Naděžda (advisor)
As a result of changes in the society, such as the increasing mobility, increasing spatial demandindgness of inhabitants and the onset of digital technologies, the architects and urbanists have been searching for new ways of urban housing developments. One of these ways is densification, i.e. an intensive use of the urban space. An intensive urban structure uses up the potential of a place to its maximum, solves several issues simultaneously and is a functional hybrid, the home of potential suburbanizers and a place of social contacts. It comes from the efforts to solve the particular issue of an over-populated, collapsing city. The aim of the thesis is to show contemporary approaches to the issue of intensive urban structures and to map out both the built and unbuilt projects. The thesis creates a system of their categorization and taxonomy. There is always a mixture of functions in play from the functional perspective. One can distinguish five categories according to the spacial conception. These categories are as follows: multiplicity, porousness, hybridity, connectivity and verticality. The public and semi-public spaces thus move to the higher levels of the city, into the city level, urban balcony or the hybrid landscape. The built projects usually tend to be impulses, in relation to the original city, to develop and revitalize the devastated city areas, brownfields, even urban sprawls. Based on the findings of this thesis, diploma and pre-diploma project assignments have been created at the architecture department at FAST VUT in Brno and the approaches to the issue have been tested in the pedagogical process. The survey in the second part of the thesis looks for the answer to the question of whether the potential inhabitants of an intensive urban structure exist, and who these people might be.
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The Municipal Baths
Vrbka, Jan ; Kyselka, Mojmír (referee) ; Makovský, Zdeněk (advisor)
Are municipal bath built next to Voronez Hotel able to compete with other such facilities? The key is to create a specific atmosphere. The bath steeps from the ground to offer views over city. Another part of the strategy is a presence of relative functions in the building – you can meet many activities, which you would not expect in public bath. But what is the most important: you can enjoy these activities in intimate environment or in the public space as well. For example: you can take a tea in a bar situated in the sixth floor with exclusive view over opposite hill or you can take different tea in a small informal teahouse hidden in the middle of the disposition. An all-embracing structure of differently juxtaposed reinforced concrete boxes creates a frame for this different human experience.
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Hybridizace mezi jelenem evropským a jelenem sikou v oblasti Doupovských hor
Kahajová, Barbora
The sika deer was introduced to the Czech Republic for the first time at the end of the 19th century, after the Second World War it also escaped into the wild. The population numbers of free-living sika deer populations are still increasing and the species causes serious ecological problems. The sika deer is also a major threat to the native European red deer, with which it crossbreeds. This thesis deals with the hybridization between the European red deer and the sika deer. The main goal was to determine the proportion of hybrid individuals between these two species in the area of the Doupovské hory Mountains, where they are in contact. During the hunting season 2020/21, 101 samples of these two species were taken in the study area. I genotyped them using 22 microsatellite loci. Previously genotyped deer samples from this area from the period 2008/09–2016/17 as well as comparative samples of sika deer and red deer from the surrounding areas and samples of the subspecies Dybowski's sika deer from enclosures were added to the evaluated dataset. Using mitochondrial DNA, the samples were divided into individual species or sika deer subspecies. A total of 560 samples were then evaluated using the Bayesian clustering analysis in the program STRUCTURE, of which 270 originated in the Doupovské hory Mountains. Based on the results, 29 hybrids were identified in the dataset, 20 in enclosures, 2 in comparative samples of sika deer and 7 in the study area Doupovské hory Mts. Five of them were detected in the season 2008/09, in the season 2020/21 analyzed by me it was only one individual. The results did not show that the proportion of hybrids in the Doupovské hory Mts has increased significantly, but they confirmed that the cross-breeding of the both species sporadicly occurs there.
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Evolution of intraspecific diversity of invasive pathogen of alder Phytophthora ×alni
Pecka, Štěpán ; Koukol, Ondřej (advisor) ; Sedlářová, Michaela (referee)
Phytophthora alni s. l. (Peronosporomycetes: Stramenopila) is an invasive pathogen causing phytophthora root and collar rot in alders. It has been known from Europe since the '90s and from the Czech Republic since 2001. Three species were found are known within species complex P. alni s. l. Two of these species hybridized in Europe and created third triploid species called Phytophthora ×alni (Phytophthora alni subsp. alni). Dozens of genotypes have been identified with the help of microsatellites in previous studies, nevertheless only one genotype (Pxa-1) was dominating and most of other genotypes were closely related to it. The trend of increasing or decreasing incidence of this genotype differed among these studies. This thesis compares changes in the P. ×alni population in Vltava basin over the last 14 years during which a significant decrease in number of available hosts of this pathogen took place. Multilocus genotypes were determined using a set of 10 microsatellite markers. Among the 94 P. ×alni isolates reliably genotyped, 23 were of different genotypes. None of these genotypes, however, were found on the same localities repeatedly (except the dominant genotype). Incidence of the dominant genotype increased over time (from 63 % to 86 %). Most of the other genotypes were only slightly...
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