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Regulation of development of mouse parthenogenetic embryos
Jettmarová, Dominika ; Fulka, Josef (advisor) ; Kaňka, Jiří (referee)
The development of mouse (Mus musculus) haploid parthenogenetic embryos does not reach the same level as normal embryos. The aim of this diploma thesis was to find out whether haploid parthenogenetic embryos of mice differ in the nucleocytoplasmic ratio. The volume of the nucleus increases with ploidity. The nucleocytoplasmic ratios of haploid embryos do not significantly change between the two-cell and four-cell stage (p = 0.052), there is a significant difference (p < 0.001) for diploid and tetraploid embryos. Non-standard nucleocytoplasmic ratio could be related to the problematic development. Understanding the regulation of preimplantational development of parthenogenetic embryos will increase the efficiency of haploid embryonic stem cell derivation.
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Differentiation in the polyploid complex Libanotis pyrenaica (Apiaceae)
Přívozníková, Hana ; Chrtek, Jindřich (advisor) ; Vít, Petr (referee)
Polyploidization belong to principal evolutionary mechanisms in plants. Although it is rather rare in the family Apiaceae, there are several interesting polyploid complexes here. The present study deals with Libanotis pyrenaica, species three previously reported ploidy levels, namely diploid (2n = 2x = 22), tetraploid (2n = 4 x = 44) and most likely very rare triploid (2n = 3x = 33). The present study aims at geographical pattern of ploidal diversity in central Europe, genetic variation and selected biological features of this species. Flow cytometru, analysis of two chloroplast DNA markers (trnF-trnL and cp018-cp020), morphometrics and in vitro germination experiments were used. The tetraploid cytotype occurs throughout the studied area; in the Czech Republic it was found in the České středohoří Mts., southern Bohemia and Moravia, in Slovakia it especially in the Carpathian mountains in western and central parts of the country and in the Pieniny Mts. in the northeast. Tetraploid cytotype occurs mainly in central-east Europe; in the Czech Republic it is common in the lowlands along the river of Labe and locally in Moravia; in Slovakia it was found along the river of Váh, in the Slovenské rudohorie Mts. and in the Belanské Tatry Mts. A mixed-ploidy population (2x, 4x) was discovered in southern...
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Impact of polyploidy on the invasive potential of Vicia cracca
Líblová, Zuzana ; Münzbergová, Zuzana (advisor) ; Mihulka, Stanislav (referee)
This work is about diploids and tetraploids of Vicia cracca species, the two commonly occurring cytotypes. The first part is devoted to the distribution of cytotypes of this species in the secondary range in North America. It was hypothesised that polyploid species become invasive more frequently than diploid species. Their greater success may be given by greater variability of genes obtained by polyploidisation and gene subfunkcionalizing. All invasive populations of Vicia cracca species involved in this study were tetraploid. Based on this we can say that only tetraploids are invasive in this secondary colonized area. Polyploid species can be better competitors thanks to their expected better growth characteristics and stress resistance. Therefore the second part of this work is testing the hypothesis that polyploids are more variable in size of different parts of the plant body and therefore more able to grow even in conditions that are not suitable for diploids. As predicted by the EICA hypothesis (evolution of increased competitive ability), secondary colonized area also provide more space for further evolution and we can expect that growth characteristics of plants from the invasive range will differ from plants of the same ploidy from the original distribution range. This part of the work...
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Regulation of development of mouse parthenogenetic embryos
Jettmarová, Dominika ; Fulka, Josef (advisor) ; Kaňka, Jiří (referee)
The development of mouse (Mus musculus) haploid parthenogenetic embryos does not reach the same level as normal embryos. The aim of this diploma thesis was to find out whether haploid parthenogenetic embryos of mice differ in the nucleocytoplasmic ratio. The volume of the nucleus increases with ploidity. The nucleocytoplasmic ratios of haploid embryos do not significantly change between the two-cell and four-cell stage (p = 0.052), there is a significant difference (p < 0.001) for diploid and tetraploid embryos. Non-standard nucleocytoplasmic ratio could be related to the problematic development. Understanding the regulation of preimplantational development of parthenogenetic embryos will increase the efficiency of haploid embryonic stem cell derivation.
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Differentiation in the polyploid complex Libanotis pyrenaica (Apiaceae)
Přívozníková, Hana ; Chrtek, Jindřich (advisor) ; Vít, Petr (referee)
Polyploidization belong to principal evolutionary mechanisms in plants. Although it is rather rare in the family Apiaceae, there are several interesting polyploid complexes here. The present study deals with Libanotis pyrenaica, species three previously reported ploidy levels, namely diploid (2n = 2x = 22), tetraploid (2n = 4 x = 44) and most likely very rare triploid (2n = 3x = 33). The present study aims at geographical pattern of ploidal diversity in central Europe, genetic variation and selected biological features of this species. Flow cytometru, analysis of two chloroplast DNA markers (trnF-trnL and cp018-cp020), morphometrics and in vitro germination experiments were used. The tetraploid cytotype occurs throughout the studied area; in the Czech Republic it was found in the České středohoří Mts., southern Bohemia and Moravia, in Slovakia it especially in the Carpathian mountains in western and central parts of the country and in the Pieniny Mts. in the northeast. Tetraploid cytotype occurs mainly in central-east Europe; in the Czech Republic it is common in the lowlands along the river of Labe and locally in Moravia; in Slovakia it was found along the river of Váh, in the Slovenské rudohorie Mts. and in the Belanské Tatry Mts. A mixed-ploidy population (2x, 4x) was discovered in southern...
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Impact of polyploidy on the invasive potential of Vicia cracca
Líblová, Zuzana ; Münzbergová, Zuzana (advisor) ; Mihulka, Stanislav (referee)
This work is about diploids and tetraploids of Vicia cracca species, the two commonly occurring cytotypes. The first part is devoted to the distribution of cytotypes of this species in the secondary range in North America. It was hypothesised that polyploid species become invasive more frequently than diploid species. Their greater success may be given by greater variability of genes obtained by polyploidisation and gene subfunkcionalizing. All invasive populations of Vicia cracca species involved in this study were tetraploid. Based on this we can say that only tetraploids are invasive in this secondary colonized area. Polyploid species can be better competitors thanks to their expected better growth characteristics and stress resistance. Therefore the second part of this work is testing the hypothesis that polyploids are more variable in size of different parts of the plant body and therefore more able to grow even in conditions that are not suitable for diploids. As predicted by the EICA hypothesis (evolution of increased competitive ability), secondary colonized area also provide more space for further evolution and we can expect that growth characteristics of plants from the invasive range will differ from plants of the same ploidy from the original distribution range. This part of the work...
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Libanotis pyrenaica - a unique polyploid complex in the family Apiaceae
Přívozníková, Hana ; Chrtek, Jindřich (advisor) ; Vít, Petr (referee)
6 Abstract Libanotis pyrenaica is sometimes neglected representative of Czech flora, a member of Apiaceae family. It grows in xerothermic habitats, on basic soils, particularly on limestones. It can be found on shrubby, stony or grassy slopes, screes, in quarries, pastures, light forests, along the roads and railroads, river banks and in castle ruins. Libanotis pyrenaica is native to the Czech Republic, but is spreading secondarily to many habitats (along the river banks, railroads). Its secondary occurrence has been documented in e.g. Eastern Bohemia. There are two ploidy levels known in the Czech Republic: 2n = 2x = 22 and 2n = 4x = 44. Diploid plants were found in Southern Bohemia (limestones of Sušicko-Horaždovice region, Českokrumlovské Předšumaví region), while the tetraploid plants were detected in Eastern Bohemia and Southern Moravia. In contrast, diploids seem to prevail throughout Europe. However, exact frequency, geographical occurrence and differentiation of both ploidies are unknown up to date. Key words: Libanotis pyrenaica, Seseli, Moon Carrot, diploid, tetraploid, cytotype differentiation, Apiaceae, flow cytometry
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Creation tetraploid varieties of the species Phlox paniculata in-vitro
Konopíková, Alžběta ; Matiska, Pavel (advisor) ; Sedlák, Petr (referee)
Phlox paniculata belongs to the group of the most important perennials and it often appears in the range of gardens and parks. Creation of tetraploid varieties of this species is important capitally from a breeding point of view, they use them mainly because of larger proportions of tetraploid cells and because of the larger number of chromosomes and greater variability in the further multiplication. In my bachelor thesis, I examined the possibility of induction of tetraploid varieties of the species Phlox paniculata with target to determine the best combination of plant-growth regulators, supporting regeneration and chemomutagens inducing tetraploids. As a plant material were chosen leafs segments size of ca 1 cm2, their cultivation passed of on MS medium. Cultivation of experiments carried throughout in an incubator with controlled temperature and photoperiod. They were investigated the effects of auxin IAA (indole-3-acetic acid) and cytokinin BAP (6-benzylaminopurine) and TDZ (thidiazuron) to regeneration of leaf segments. They were also investigated the effects of chemomutagens colchicine and oryzalin to creation of tetraploids. The best results of regeneration were obtained with the combination of MS medium with TDZ 3 mg . l-1 and IAA 1 mg . l-1, in this case control variant of this medium reached 100 % regeneration of leaf segments. As less suitable chemomutagen for this thesis showed colchicine, in this case was a 100 % mortality of leaf segments cultivar 'Starfire'. On the other side as more effective herbicide showed oryzalin at concentration 14 mg . l-1 applied for 14 days, in this variant was the percentage of recovery 18,6 %. Subsequent regeneration of explants after effect of chemomutagens is time-consuming, and therefore has not been possible to verify the actual amount of potentially obtained tetraploids yet . This topic will be the subject of follow-up thesis of another student.
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