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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Ecological genetics of floral longevity in Campanula rotundifolia, the Alpine Harebell /

Giblin, David Emmett, January 2001 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
2

Ecological genetics of floral longevity in Campanula rotundifolia, the Alpine Harebell

Giblin, David Emmett, January 2001 (has links)
Thesis (Ph. D.)--University of Missouri-Columbia, 2001. / Typescript. Vita. Includes bibliographical references. Also available on the Internet.
3

Biotransformace monepantelu u rostlin (Campanula rotundifolia, Plantago lanecolata) / Biotransformation of monepantel in plant (Campanula rotundifolia, Plantago lanceolata)

Crhová, Anna January 2018 (has links)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Biochemical Sciences Candidate: Bc. Anna Crhová Supervisor: RNDr. Lucie Stuchlíková Raisová, Ph.D. Title of diploma thesis: Biotransformation of monepantel in plants (Campanula rotundifolia, Plantago lanceolata) Anthelmintics are veterinary drugs used to eliminate disease caused by parasitic worms. Monepantel (MOP) is a representative of amino-acetonitrile derivatives. This relatively new group of drugs is effective on helminthic strains, which are resistant to classic therapy (benzimidazoles, makrocyklic lactones, imidazothiazoles). Due to high consuption of these drugs, it is important to find out their fate in the exposed organisms. Anthelmintics are in contact with the environment and they can affect terrestrial and aquatic organisms. Their various forms can be accumulate in plants. These plants can be eaten by the animal, which may lead to development of resistance in helminths. In addition, the physiology of plants and animals may be disrupt and, consequently, biodiversity loss may occur. The aim of this study was to determine the biotransformation processes occurring in ribwort plantain (Plantago lanceolata) and harebell (Campanula rotundifolia) after low concentrations of MOP. Suspensions of both plants cells...
4

Endemický taxon Krkonoš Campanula bohemica: zhodnocení rizika hybridizace s C. rotundifolia / Risk assessment of interspecific hybridization between endemic Campanula bohemica and widespread C. rotundifolia s.l.

Hanušová, Kateřina January 2014 (has links)
The thesis deals with phenotypic, ploidy and genetic variation of two Campanula species occurring in the Krkonoše Mts., namely the endemic C. bohemica and widespread C. rotundifolia subsp. rotundifolia. For comparative purposes subspecies sudetica of the latter species was also included. The main aim was to get insight into population structure and assess the threat of interspecific hybridization to the survival of the endemic bluebell. Flow cytometry, distance-based morphometrics and molecular analysis were used to address these questions. Three distinct groups of fluorescence intensities were revealed by flow cytometry, corresponding to DNA diploids, tetraploids and pentaploids. While diploids morphologically matched the nominate subspecies of C. rotundifolia, tetraploids corresponded either to C. rotundifolia subsp. sudetica or C. bohemica. Most populations from the Krkonoše Mts. were uniform although a sympatric growth of diploids and tetraploids was encountered in 12 populations. Only two pentaploids individuals, most likely of hybrid origin, were found, which indicated that interspecific hybridization is much less common than previously assumed. The two tetraploid taxa were distinguished by molecular markers. A combination of flow cytometry and molecular analyses thus allowed reliable...
5

Populační struktura a fenotypová diferenciace Campanula moravica / Population cytotype structure and phenotypic variation of Campanula moravica

Šemberová, Kristýna January 2013 (has links)
Polyploidisation plays a major role in plant evolution. It can also cause taxonomic complexities as morphological differences are often blurred in higher ploidy levels. One of the taxonomically-intrigued groups of Central Europe is C. rotundifolia agg. Three ploidy- heterogeneous species are traditionally recognized in the Czech Republic: C. gentilis (2x, 4x), C. rotundifolia (2x, 4x) and C. moravica (4x, 6x). The thesis examines karyological and phenotypic variation of C. moravica, in the centre of its distribution (the Czech Republic and Slovakia). With the aid of modern biosystematics tools (DNA flow cytometry, multivariate morphometrics), marked discrepancies were revealed between published data and actual cytotype distribution pattern and morphological variation. In contrast to literature records, cytotype distribution in C. moravica is largely parapatric, with hexaploids occurring in Pannonian basin and tetraploids in Central and Eastern Slovakia. The type population of presumed tetraploids turned out to be hexaploid. The coexistence of one majority (4x) and six minority cytotypes (2x, 3x, 5x, 6x, 8x, 9x) was found in one population in central Slovakia and represent the most salient case of ploidy coexistence ever reported. Multivariate morphometrics showed that species identification on the...
6

Abelhas oligoléticas e plantas hospedeiras: ecologia cognitiva e da polinização

Milet-Pinheiro, Paulo 31 January 2011 (has links)
Made available in DSpace on 2014-06-12T15:04:43Z (GMT). No. of bitstreams: 2 arquivo6595_1.pdf: 6505402 bytes, checksum: 0871b5f9bca124f5e8f850bdc07edeea (MD5) license.txt: 1748 bytes, checksum: 8a4605be74aa9ea9d79846c1fba20a33 (MD5) Previous issue date: 2011 / Conselho Nacional de Desenvolvimento Científico e Tecnológico / O presente estudo investigou a interação entre abelhas oligoléticas, que coletam pólen em plantas de um mesmo gênero ou família, e suas plantas hospedeiras, destacando aspectos adaptativos da ecologia cognitiva e da polinização. Abelhas oligoléticas Chelostoma rapunculi apresentam adaptações neurológicas visuais e olfativas que controlam a atração e preferência inata pelos sinais florais da planta hospedeira Campanula trachelium. Baseada nessas adaptações Ch. rapunculi é capaz de reconhecer flores de Ca. trachelium, caracterizadas por sinais visuais repetitivos na natureza, i.e. cor UV-azul, mas, ao mesmo tempo, por sinais olfativos altamente específicos, as espiroacetais. Esses voláteis florais raros são os únicos capazes de atrair abelhas inexperientes de Ch. rapunculi e são, consequentemente, a chave para o reconhecimento inato da planta hospedeira Ca. trachelium. Isso indica que, pelo menos nessa espécie, a oligoletia deve ser controlada por limitações neurológicas, geneticamente determinadas. Na interação entre a abelha oligolética Ceblurgus longipalpis e a planta hospedeira Cordia leucocephala, foi evidenciada uma dependência mútua, onde a planta distílica depende da abelha como único polinizador e a abelha depende da planta como fonte exclusiva de pólen (monoletia). Nessa associação, adaptações morfológicas em ambos os parceiros foram evidenciadas. A abelha Ce. Longipalpis desenvolveu peças bucais alongadas e pilosas incomuns entre abelhas de línguas curtas para explorar o pólen escondido de flores longistilas de Co. leucocephala e o néctar na base do tubo floral estreito, ambos inacessíveis para outros visitantes florais
7

Constraints on sexual reproduction and seed set in <em>Vaccinium</em> and <em>Campanula</em>

Nuortila, C. (Carolin) 05 June 2007 (has links)
Abstract Plant reproductive success is affected by a number of factors, such as climatic conditions and plant resource status during flowering and fruiting, and pollen origin in fertilization. In the present thesis project, different aspects of plant reproductive ecology were investigated in order to identify constraints on sexual reproduction and seed set in two clonal dwarf shrubs (Vaccinium myrtillus and V. vitis-idaea) and one long-lived perennial herb (Campanula rotundifolia). The work comprised phenological observations and experiments with the clonal shrubs at natural boreal forest sites in the Oulanka National Park in northern Finland. The impact of mycorrhiza on C. rotundifolia fitness traits was tested in hand pollinations in a greenhouse experiment. Pollen origin had some effect on fruit set, and had strong effects on the number of matured seeds in all three species. Seed yield reductions upon hand self-pollination as compared with hand cross-pollination were attributed to inbreeding depression in V. myrtillus, and presumably to partial self-incompatibility in C. rotundifolia. V. myrtillus and V. vitis-idaea showed a population structure where the number of matured seeds per fruit increased with increasing distance between pollen donor and pollen recipient. Clonal growth in concert with the foraging behaviour of bumblebee pollinators is thought to cause the possibility of either uniparental or biparental inbreeding, with a strong effect on the number of matured seeds per berry. In a flower-removal experiment lasting three years, costs of fruiting to future fecundity and vegetative traits were observed, but not to future survival in V. vitis-idaea and V. myrtillus. The response was more pronounced in the evergreen than in the deciduous species. In Campanula rotundifolia, mycorrhiza was associated with a cost to the plants' reproductive effort, as plant biomass and the number of flowers produced per plant were decreased in mycorrhizal plants in comparison with non-mycorrhizal plants. There was no difference in seed number, seed weight or germination between the seeds of mycorrhizal and non-mycorrhizal plants. However, the offspring of mycorrhizal plants had a higher relative growth rate, while also having a higher seed phosphorus concentration. In summary, sexual reproduction was variably constrained by previous reproduction in Vaccinium, and contrary to expectations, by mycorrhiza in Campanula. However, mycorrhiza had positive effects on some measures of offspring fitness. In all three species, self-pollination limited seed production.
8

Pátrání po původu vysokohorských endemických zvonků z okruhu Campanula rotundifolia agg. ve střední Evropě. / Searching for the origin of high-altitude endemic harebells from Campanula rotundifolia agg. in central Europe.

Folbrová, Magdaléna January 2019 (has links)
Complex Campanula rotundifolia agg. is rich in endemic species, especially in the high- elevated mountain ranges. Extreme climatic conditions in the subalpine habitats can lead to a convergence in plant's morphology between plants isolated in different mountain ranges. Because of the lack of morphological differentiation, it is very difficult to reconstruct the evolutionary history of bellflowers C. scheuchzeri from the Alps, C. bohemica from the Krkonoše Mountains and C. tatrae from the Western Carpathians. A similarity in morphology and the same ploidy level can suggest vicariance from a large area of an ancestor species. However, regarding the continuous morphological variation, the high-altitudinal endemics could have originated by local adaptation from originally low-land species. DNA-ploidy level and genome size were detected by flow cytometry. Taxonomically important characters were found using multivariate morphometric analysis. The phenotypic plasticity of the taxon C. tatrae was tested by a cultivation experiment. Genetic structure of the studied species was revealed using molecular marker - microsatellites (7 variable primers). Studied taxa were tetraploids, but some possessed different genome size. The morphological differentiation was mainly due to characters like calyx lobes length...
9

Genetická diverzita a struktura populací Campanula glomerata na regionální škále v Bílých Karpatech / Genetic diversity and structure of populations of Campanula glomerata on regional scale in White Carpathians

Černá, Mariana January 2020 (has links)
Habitat fragmentation can adversely affect species populations due to reduced genetic diversity and increased population differentiation due to habitat isolation, reduced population size, and disruption of gene flow. Many species suffer from habitat fragmentation and isolation, and Campanula glomerata is a good example of a species that is noticeably declining in many places due to changes in landscape management. The question is how the model species responds to these changes and whether is the change are reflected in genetic diversity and population structure. The aim of this work is to determine the degree of genetic diversity and to reveal the genetic structure of populations of the model species C. glomerata on a small regional scale in the White Carpathians. This system will allow us to compare populations from two different regions that have been affected to varying degrees by agricultural intensification and fragmentation in the last century. It is a southwestern and northeastern part of the region, which differs from each other in the history of management in the landscape, but also in the continuity of meadows, species composition and environmental conditions. For this purpose, I developed and optimized a total of 16 usable microsatellite markers, 4 of which come from related species of...

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