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Decisions in seed reproduction in plants
Mašková, Tereza
Seed reproduction is a key part of the life cycle of the most plant species. It allows for the dispersal of species in space and time and, thus, significantly affects dynamics of plant populations and communities. Seed formation, germination and seedling establishment are subjected to selection pressures from the environment and lead to optimization of maternal investments (maternal care), manifested by the number of seeds and amount and composition of nutrients stored in individual seeds. The thesis aims to answer two questions: (i) whether maternal investments in terms of seed mass and seed nutrient stoichiometry is optimized according to the environmental conditions in which seedling development is expected and (ii) how nutrient availability, considering nutrients both stored in the seed by the mother plant and those available in the substrate, affects seedling growth and development. To answer the first question, we focused on interspecific comparisons of seed nutrient stoichiometry linking it with data on seed mass and species niche along gradients of nu- trient availability. We used a phylogenetically informed comparative approach to explore the ratio between phosphorus, nitrogen and nonstructural carbon in seeds from 510 wild herbaceous species. We analyzed seed nutrient stoichiometry with...
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Decisions in seed reproduction in plants
Mašková, Tereza
Seed reproduction is a key part of the life cycle of the most plant species. It allows for the dispersal of species in space and time and, thus, significantly affects dynamics of plant populations and communities. Seed formation, germination and seedling establishment are subjected to selection pressures from the environment and lead to optimization of maternal investments (maternal care), manifested by the number of seeds and amount and composition of nutrients stored in individual seeds. The thesis aims to answer two questions: (i) whether maternal investments in terms of seed mass and seed nutrient stoichiometry is optimized according to the environmental conditions in which seedling development is expected and (ii) how nutrient availability, considering nutrients both stored in the seed by the mother plant and those available in the substrate, affects seedling growth and development. To answer the first question, we focused on interspecific comparisons of seed nutrient stoichiometry linking it with data on seed mass and species niche along gradients of nu- trient availability. We used a phylogenetically informed comparative approach to explore the ratio between phosphorus, nitrogen and nonstructural carbon in seeds from 510 wild herbaceous species. We analyzed seed nutrient stoichiometry with...
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Decisions in seed reproduction in plants
Mašková, Tereza ; Herben, Tomáš (advisor) ; Thompson, Ken (referee) ; Těšitel, Jakub (referee)
Seed reproduction is a key part of the life cycle of the most plant species. It allows for the dispersal of species in space and time and, thus, significantly affects dynamics of plant populations and communities. Seed formation, germination and seedling establishment are subjected to selection pressures from the environment and lead to optimization of maternal investments (maternal care), manifested by the number of seeds and amount and composition of nutrients stored in individual seeds. The thesis aims to answer two questions: (i) whether maternal investments in terms of seed mass and seed nutrient stoichiometry is optimized according to the environmental conditions in which seedling development is expected and (ii) how nutrient availability, considering nutrients both stored in the seed by the mother plant and those available in the substrate, affects seedling growth and development. To answer the first question, we focused on interspecific comparisons of seed nutrient stoichiometry linking it with data on seed mass and species niche along gradients of nu- trient availability. We used a phylogenetically informed comparative approach to explore the ratio between phosphorus, nitrogen and nonstructural carbon in seeds from 510 wild herbaceous species. We analyzed seed nutrient stoichiometry with...
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Plant competition in the early ontogeny
Čiháková, Klára ; Weiser, Martin (advisor) ; Fendrych, Matyáš (referee)
Competitive impacts on early stages of plant ontogeny are being reviewed in this thesis. Those processes select for evolutionary or phenotypically plastic responses in timing of emergence, seed morphological properties, maternal effects and reaction on environmental cues. However, pattern of the strong selective pressure is sometimes not apparent, due to the lack of data and knowledge on the influence of the other factors in plant's life.
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Strategies in aboveground space occupancy in herbs from disturbed habitats
BARTUŠKOVÁ, Alena
Disturbance is an important phenomenon affecting plant lives and shaping plant strategies in disturbed habitats. A variety of ecological concepts on individual plant response to injury has been proposed for specific natural ecosystems or growth forms. In central Europe, man-made habitats are often cases of disturbed places, so the aim of the thesis was to apply four chosen concepts on them. The thesis is composed of four original studies performed in two model ecosystems: recurrently disturbed ruderal place and regularly mown central European meadow. The occupying of the aboveground space after a disturbance event was studied here either as renovation of biomass or architecture. Regenerative strategies in herbs occupying disturbed habitats were described and confronted with concepts proposed originally for ecosystems subjected to natural disturbance regimes.
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