National Repository of Grey Literature 6 records found  Search took 0.01 seconds. 
Cardamine dentata, its distribution in Central Europe and relatinoship to C. pratensis
Holič, Filip ; Marhold, Karol (advisor) ; Chrtek, Jindřich (referee)
This thesis summarizes the documented information on the distribution of Cardamine dentata Schult. of the family Brassicaceae in the Czech Republic; it deals with the chromosome numbers and with ploidy levels of this species. Microsatellite markers were used to evaluate the potential relationships of C. dentata with other species of the group C. pratensis. Using a revision of available herbarium material it was found that the optimal conditions for the occurrence of C. dentata in the Czech Republic are in the phytogeographical regions of Thermophyticum and Mezophyticum at altitudes of 150-650 m a.s.l. No karyological data on this species were previously published from the area of the Czech Republic; using the flow cytometry and chromosomes counting it was revealed that in the area of the Czech Republic, populations with decaploid and undecaploid levels of ploidy occur. With help of microsatelite markers, it was confirmed that plants of C. dentata are genetically different from the other species of the C. pratensis group. Keywords: Cardamine, Cruciferae, microsatelite markers, chromosome numbers, geographical distribution, Czech Republic
Introgressive zone of Arabidopsis lyrata and A. arenosa in Central Europe
Hojka, Jakub ; Marhold, Karol (advisor) ; Španiel, Stanislav (referee)
Genetic composition of hybrid zones often reflects geographical and ecological gradients. Hybrid zone of Arabidopsis lyrata and A. arenosa in Central Europe can be convenient model system for testing such hypothesis. These are well circumscribed but still interfertile, and their offspring is fully fertile. Besides repeated hybridisation events, the current state is complicated by the autopolyploidisation events of one of the parents, namely A. lyrata, which is present in the area studied both as diploid and tetraploid. This hybrid zone was already described in previous publications, which showed certain gradient of introgression. Moreover, the area of the hybrid zone represents a transition between Alpine and Pannonian climate along an altitudinal gradient leading from the Prealps to the lowland Wienerwald. The current thesis is the as yet most detailed study of this hybrid zone both in respect of number of studied populations and the amount of data acquired using the methods of RAD Sequencing, multivariate morphometrics and flow cytometry. The analysis of genetic data showed a gradient of introgression, where parental populations are placed at opposite ends, whereas genetically intermediate hybrids are placed in its centre. Analysis of the genome size showed an additional gradient, where hybrids...
Is there any influence of ecological gradient on the introgression and its evolutionary consequences in the genus Arabidopsis?
Hojka, Jakub ; Marhold, Karol (advisor) ; Mráz, Patrik (referee)
1 Hybridization, introgression and polyploidy, especially in their combination, belong to the most important speciation processes in vascular plants. Athough basic features of these processes are generally well known, their cases in particular groups of plants and concrete cases differ a lot and their studies often bring interesting results. In the genus Arabidopsis several cases of combined hybrid and polyploid speciation are known (e.g. A. kamchatica, A. suecica) and there are also cases where we expect introgressive hybridization (e.g. between A. arenosa and A. petraea). The aim of the bachelor thesis is an evaluation of known cases of homo- and heteroploid introgressive hybridization and hybrid speciation in the genus Arabidopsis in the context of similar cases in the family Brassicaceae and perhaps also other families of vascular plants. Next aim is to design method of detailed evaluation of the introgressive zone of A. arenosa and A. petraea (= A. lyrata subsp. petraea) in Central Europe using mophological, cytometric and molecular evidence as well as ecological parameters of studied localities. Set of morphological characters will be tested on the currently available material of A. arenosa that is cultivated at CEITEC Brno as part of the finalised GACR project.
Phylogeography of temperate plant species with the focus on Central Europe
Daneck, Hana ; Marhold, Karol (advisor) ; Štech, Milan (referee) ; Tremetsberger, Karin (referee)
Phylogeography of temperate plant species with the focus on Central Europe Ph.D. Thesis Hana Daneck Charles University Prague Faculty of Science Department of Botany Supervisor: Prof. RNDr. Karol Marhold, CSc. Consultant: Mgr. Tomáš Fér, Ph.D. Praha 2012 2 Summary This thesis presents contribution to clarification of postglacial history of temperate plant taxa in Europe with the focus on especially interesting region of Central Europe, for which diverse roles in postglacial plant histories were suggested. The first part of the thesis summarises general phylogeographical views and methodological approaches with the respect to species history after the last ice age in Europe. Further, the most important aspects of phylogeography of European temperate plant taxa are discussed. The second part contains a set of papers dealing with selected European temperate plant species, for which phylogeographical patterns throughout their present distribution area were inferred, including assumptions on the origin of their contemporary Central European populations and comparisons with another previously studied species. Paper 1: Phylogeographic pattern of the European forest grass species Hordelymus europaeus: cpDNA evidence. This paper presents phylogeographical pattern based on chloroplast haplotype variation covering the...
Cytogeography of Cardamine amara in the Czech Republic and the origin of tetraploid populations
Krásná, Iva ; Koutecký, Petr (referee) ; Marhold, Karol (advisor)
Diskuse ____________________________________________________________________________________________________________________________________________________ 100 Neiova genetická diverzita byla u tetraploidních populací na okraji areálu (6245, 6249) nižší, ale jinak nebyla v míře diverzity v geografickém rozmístění populací žádná zákonitost. U triploidní populace nebyla zaznamenána žádná genetická diverzita, což opět poukazuje, že se jedná o klon. Výsledný graf PCoA analýzy od sebe oddělil skupiny diploidních a tetraploidních jedinců. Diploidní populace z kontaktních a izolovaných oblastí jsou rovnoměrně promíšené. Tetraploidi z kontaktní oblasti se objevují v prostoru blíž k diploidům, což by mohlo indikovat omezený ale existující genový tok od diploidů k tetrapoidům. Triploidní populace se nachází v prostoru kontaktních a izolovaných tetraploidních populací. Pravděpodobně díky jejich existenci dochází k sekundárnímu kontaktu a genovému toku mezi ploidními úrovněmi. Bayesova analýza odlišila jedince do čtyř shluků. Diploidní jedinci měli ve svém shluku zařazeného jednoho tetraploida. Další shluk byl tvořen oddělenou triploidní populací. Tetraploidi tvořily shluk v němž byla odděleně vyčleněná populace 6245 Kozolupy. Dendrogram (neighbour-joining tree, NJ) od sebe oddělil větev diploidů a větev, která...

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