Original title: (A)sexual Life of Liverworts
Translated title: (A)sexual Life of Liverworts
Authors: HOLÁ, Eva
Document type: Doctoral theses
Year: 2015
Language: cze
Abstract: This thesis comprises of two published papers and one accepted manuscript, focused on various aspects of liverwort reproduction. Treated aspects include patterns of asexual reproduction, sex ratio and sex-specic pattern in vegetative growth, and patterns of genetic variation and spatial genetic structure of populations differing in availability of substrate on localities and the population connectivity, and consequently in size, density, and prevailing reproductive mode. These characteristics were studied on representatives of the family Scapaniaceae s.l., belonging to the largest liverwort order Jungermanniales. The results showed that asexual propagules were formed and present in course of the whole growing season and can be considered as a sufficient substitution for sexual reproduction. In contrast with the female-biased sex ratio observed earlier in most dioicous bryophytes, unexpectedly high male-biased sex ratio was observed in the aquatic liverwort, which was speculated to represent a strategy to overcome sperm dilution in aquatic environment. In addition, no size differences between female and male shoots were detected, although the evidence for higher cost of sexual reproduction in females was found. The study of population genetic structure has shown that even small and predominantly asexually reproducing populations are important sources of genetic variation. However, we were able to demonstrate notably low levels of gene flow among populations where habitat fragmentation poses a significant barrier to dispersal of diaspores. The fine scale study of spatial genetic structure revealed a strong aggregation of genotypes, particularly in smaller populations, and at the same time showed that asexual reproduction is an efficient mean of maintaining the populations at not only the short distances, given the spatial extent of clones spanning dozens of meters.
Keywords: asexual reproduction; genetic variation; liverworts; sex-ratio
Citation: HOLÁ, Eva. (A)sexual Life of Liverworts. České Budějovice, 2015. disertační práce (Ph.D.). JIHOČESKÁ UNIVERZITA V ČESKÝCH BUDĚJOVICÍCH. Přírodovědecká fakulta

Institution: University of South Bohemia in České Budějovice (web)
Document availability information: Fulltext is available in the Digital Repository of University of South Bohemia.
Original record: http://www.jcu.cz/vskp/13945

Permalink: http://www.nusl.cz/ntk/nusl-200684


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Universities and colleges > Public universities > University of South Bohemia in České Budějovice
Academic theses (ETDs) > Doctoral theses