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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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Conservation aspects of endemism in Central Europe with special respect to genus Sorbus
Tesařová, Anna ; Urfus, Tomáš (advisor) ; Macková, Lenka (referee)
Endemit is an organism living exclusively within a particular area on Earth. There are several mutually interconnected mechanisms leading to endemism i.e. allopathic speciation, polyploidization, hybridization and apomixis. This thesis deals with describing particular modes of endemic speciation and their occurrence. The most significant concept is certainly discrimination of paleoendemites and neoendemites. Paleoendemites are very rare and within Central Europe occur scarcerly only in Western Carpathians. Neoendemites are hardly comparable among Central European states. The concentration of endemics is closely related to the global centers of diversity that are distributed in highly unbalanced way. The genus Sorbus is essential group with regard to endemism in Central Europe. That is why the experimental part of my thesis was focused on flowcytometric analyses (absolute genome size and DNA ploidy level) of 13 endemic Sorbus species. Triploidy was proved to be prevailing ploidy level. Among triploid samples 6% of variation was recorded. The absolute genome size of the remaining endemic taxa indicated tetraploid level.
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Conservation aspects of endemism in Central Europe with special respect to genus Sorbus
Tesařová, Anna ; Urfus, Tomáš (advisor) ; Macková, Lenka (referee)
Endemit is an organism living exclusively within a particular area on Earth. There are several mutually interconnected mechanisms leading to endemism i.e. allopathic speciation, polyploidization, hybridization and apomixis. This thesis deals with describing particular modes of endemic speciation and their occurrence. The most significant concept is certainly discrimination of paleoendemites and neoendemites. Paleoendemites are very rare and within Central Europe occur scarcerly only in Western Carpathians. Neoendemites are hardly comparable among Central European states. The concentration of endemics is closely related to the global centers of diversity that are distributed in highly unbalanced way. The genus Sorbus is essential group with regard to endemism in Central Europe. That is why the experimental part of my thesis was focused on flowcytometric analyses (absolute genome size and DNA ploidy level) of 13 endemic Sorbus species. Triploidy was proved to be prevailing ploidy level. Among triploid samples 6% of variation was recorded. The absolute genome size of the remaining endemic taxa indicated tetraploid level.
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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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