Home > Search Results: Zozomová, Judita
Search:
Search Tips :: Advanced Search
Search collections:
Sort by: Display results: Output format:
National Repository of Grey Literature 2 records found  Search took 0.01 seconds. 
Microevolutionary processes and inter-cytotype interactions in mixed-ploidy populations
 Trávníček, Pavel ; Suda, Jan (advisor) ; Frajman, Božo (referee) ; Zozomová, Judita (referee)
[Abstract] This thesis is aimed at better understanding of cytotype co-existence in mixed- ploidy populations with an emphasis on a microevolutionary processes behind it. Our past knowledge was based on a few thoroughly investigated model taxa like Chamerion angustifolium and Heuchera grossulariifolia, but some generalizations seem to be premature in the light of new findings. A detailed research of other taxa included in the thesis showed that polyploid complexes can vary dramatically in their ability to cope with the co-existence of cytotypes in mixed-ploidy popu- lations. Whereas mixed-ploidy populations are virtually lacking in some species (an example being Vicia cracca, Paper III.), ploidy-heterogeneous populations are very common in others, maintained by free mating interactions and the absence of reproductive isolation among cytotypes (e.g. Pilosella echioides, Paper II.). The strenght and cumulative effect of various breeding barriers (both pre- or post- zygotic) govern the position of a particular multi-ploidy complex between these two extremes and co-determine the type of cytotype co-existence in its mixed- ploidy populations. Despite the fact that the number of studies revealing cytotype co-existence has been increasing rapidly, evolutionary background and consequences of such co-...
Detailed record
Molecular phylogeny and evolutionary trends in Hieracium (Asteraceae, Lactuceae)
 Krak, Karol ; Fehrer, Judith (advisor) ; Zozomová, Judita (referee) ; Nieto Feliner, Gonzalo (referee)
The hawkweed subgenus Hieracium s. str. is notoriously known for its extreme morphological variability and variation in ploidy levels that is associated with differences in modes of reproduction. Extensive past hybridization is supposed for the subgenus, but recent hybridization was evidenced only in few cases. The subgenus attracts the attention of botanists already for more than a century. Therefore the species diversity is largely examined and the taxonomy of the subgenus is well elaborated, although several contradictory taxonomic concepts exist. However the relationships among the species are unknown and haven't been studied yet. The investigation of these relationships from a phylogenetic perspective using molecular approaches was the main aim of the presented thesis. Basic species (both diploid and polyploid), representing morphologically unique taxa, that are supposed to be the basic evolutionary units of the subgenus were studied. The sequences of two intergenic spacers of the cpDNA (trnT-trnL and trnV-ndhC) and the external transcribed spacer of the nuclear ribosomal DNA (nrDNA ETS) were analyzed. Moreover, three new low-copy nuclear markers with higher variability than nrDNA and cpDNA markers were developed and their suitability for phylogenetic studies in Hieracium s. str. was...
Detailed record

Interested in being notified about new results for this query?
Subscribe to the RSS feed.
Digital Repository :: Search :: Submit :: Personalize :: Help
Powered by Invenio v1.1.2
Maintained by admin.invenio@techlib.cz
This site is also available in the following languages:
Česky  English