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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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Differenciation in the Galium palustre group in central Europe
Dohnalová, Pavla ; Kaplan, Zdeněk (advisor) ; Knotek, Adam (referee)
The aim of this work is to summarize the current knowledge about the Galium palustre complex in Central Europe. It is a polyploid complex, which has involved polyploidization and hybridization in its evolution. Individual cytotypes somewhat differ in quantitative characters and in ecology and show considerable morphological variation. For this reason, the taxonomy of the group is unclear and the opinions on the cytotype classification differ. There are two species in the Galium palustre complex distinguished in the Czech Republic, the diploid Galium palustre and the octoploid Galium elongatum. Exact data regarding their distribution and morphological variation are not known and therefore this thesis will be followed by a master's thesis, where modern methods will be used to clarify the issue. Key words: polyploidization, hybridization, Galium palustre, Galium elongatum morphological variation
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Hybridization within genus Sorbus in Central Europe
Ondříčková, Klára ; Urfus, Tomáš (advisor) ; Knotek, Adam (referee)
The genus Sorbus is a very complicated group. Thanks to mikroevolutionary processes such as interspecific hybridization, polyploidy and apomixis produce large quantities of genetically distinct lineages. Hybridization between basic species (S. aria agg., S. torminalis, S. aucuparia, S. chamaemespilus) formed hybridogenous group which speciation is often associated with just polyploidy and apomixis formation, often only optional. Another type of reproduction is observed vegetative layering. The whole group is mophological very variable and taxonomic categorization of certain groups is not solved yet. The work also includes an introduction to the group Sorbus sudetica agg., which representative S. sudetica is endemic to Giant Mountains. At the end there are the current results and the methods that will be used for the master's thesis.
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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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Endemic plants of the Sudeten Mts., with emphasis on the taxonomically controversial Primula elatior subsp. corcontica
Konečná, Veronika ; Suda, Jan (advisor) ; Knotek, Adam (referee)
The endemic species of the Czech Republic still present a hot topic. Effective research of this topic means understanding of factors which create and influence endemism. With the exception of the Alps and the Carpathians, endemics are relatively very rare in Central Europe. In the Czech Republic they are concentrated mainly in subalpine (alpine) areas in the High Sudetes. Majority of the Czech endemics is of relatively recent origin. They have not well differentiated yet and so it is difficult to taxonomically evaluate them. Endemics of the High Sudetes have probably originated in Holocene with the exception of apomicts, e.g. species of genus Hieracium, which have likely originated even earlier. The origin of most of the Sudetes endemics was possible due to geographic isolation of small populations called peripatric speciation. Peripatric speciation is probably responsible for the origin of taxonomically uncertain endemic species Primula elatior subsp. corcontica, which is a subspecies of highly variable P. elatior. In the Czech Republic occur three subspecies of P. elatior - subsp. corcontica, subsp. elatior and subsp. tatrensis. These subspecies are differentiated in the morphology of leaves and in their distribution. The description of P. elatior subsp. corcontica was based on morphological...
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Evolutionary history of polyploid complex Galium pumilum in Central Europe
Knotek, Adam ; Kolář, Filip (advisor) ; Urfus, Tomáš (referee)
The thesis summarizes current knowledge about the polyploid complex of Galium pummilum agg. in Central Europe. This work should provide a theoretical background for a following diploma thesis. Most species of the aggregate are difficult to be determined due to considerable morphological variability and a complex evolutionary history probably involving recurrent polyploidization and hybridization events. Currently, new molecular methods are changing our opinion on the taxonomical classification within the group. Except for G. pumilum MURRAY, the other species show rather disjunctive distribution and are found on relict habitats. This could be caused by postglacial migration and subsequent area fragmentation. Most of the previous studies focused on Galium were published by Friedrich Ehrendorfer, who since the 50th defined division of the complex on the basis of chorological, karyological and morphological data. With new molecular methods, his hypotheses are now exposed to verification. Galium sudeticum TAUSCH. represents an enigmatic and vulnerable taxon of the Czech flora, that raises various interesting questions from both evolutionary and conservation points of view. It has a remarkable disjunct distribution in the Giant mountains (Krkonoše) and in one serpentine area in western Bohemia...
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