National Repository of Grey Literature 122 records found  beginprevious102 - 111nextend  jump to record: Search took 0.00 seconds. 
The changes of Rubisco amount in Norway spruce grown at gradient of altitudes
Tomasz, Teresa ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
The study deals with differences of Rubisco enzyme content in Norway spruce needles (Picea abies L.) growing at different altitudes, thus at different concentrations of carbon dioxide. The collection of samples was performed in Jeseníky by Global Change Research Centre, Academy of Sciences of the Czech Republic. The samples of exposed and shaded needles were collected from 39 spruce trees in three altitudes – low (L), medium (M) and high (H). To separate Rubisco enzyme, the SDS-PAGE method was used, the content od Rubisco was determined by computer densitometry. The results of exposed needles confirmed that Rubisco content decreases with increasing altitude, however, in the case of shaded needles, there was no proof of a significant influence of altitudes on Rubisco enzyme amount. At low altitude, Rubisco content was significantly higher in exposed needles in comparison with shaded needles. At medium and high altitude no significant difference was detected between exposed and shaded needles.
Impact of elevated carbon dioxide concentration on Rubisco content in Fagus sylvatica and Picea abies
Hamříková, Dominika ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
In this bachelor’s thesis content of Rubisco in beech (Fagus sylvatica) and Norway spruce (Picea abies) was studied. The plants were cultivated in conditions with ambient carbon dioxide concentration (350 mol·mol-1) and elevated carbon dioxide concentration (700 mol·mol-1). The content of Rubisco in exposed and shaded leaves or needles was compared. The content of Rubisco was determined by SDS-PAGE method. A significant decrease in Rubisco content was demonstrated in conditions E versus A in shaded beech leaves. In other cases, the decrease was not so significant. A comparison of exposed and shaded needles also did not show a statistically significant difference, but in shaded beech leaves against exposed leaves Rubisco content was significantly lower, especially in conditions E.
Vliv zvýšené koncentrace CO2 a sucha na rychle rostoucí dřeviny
Vágner, Lukáš
The main objective of this study was to determine the effect of elevated CO2 and drought on growth of fast-growing trees, hence hybrids of poplar Populus nigra and Populus maximowiczii on experimental station Domanínek. These parameters were measured: photosynthesis, reflectance, fluorescence of chlorophyll and content of chlorophylls and flavonols. The results show a demonstrable effect of greater regulatory abilities stomatas at elevated CO2 concentration, which leads to greater efficiency of water use. Decisive influence on leaf area, specific leaf area and the dry weight has the effect of drought. However, for specific leaf area, contrary to expectations, there was an noticeable increase during drought period. In the case of other characteristics come to reduce them. By contrast specific leaf area slightly decreases at elevated CO2 concentration. Rate of photosynthesis increases with increasing concentrations of CO2, while the effect of drought dampens these characteristics and also reduces the chlorophyll content. Increasing concentration of CO2 during the experiment also leds to an increase in NDVI index, which shows increased chlorophyll content. The values of fluorescence at two concentrations of CO2 when exposed to drought stress differed minimally. The maximum quantum yield of photosystem II is slightly higher at elevated CO2 concentration. Overall, it can be summarized that in the short-term effect of drought stress in hybrid poplar, increased concentration of CO2 increases water use efficiency and thus to mitigate the impact of drought on photosynthetic parameters.
Mechanism of photoprotection in photosynthetic proteins
KUTHANOVÁ, Eliška
Nonphotochemical quenching is an important protective mechanism of photosynthetic proteins against excessive irradiation. In this work, isolation of native light harvesting antennae from alga Chromera velia was optimized using methods of sucrose density centrifugation, isoelectric focusing, ion exchange chromatography and gel electrophoresis. Moreover, the ability of light harvesting antennae to trigger nonphotochemical quenching was studied in vivo and in vitro.
Mobility of photosynthetic proteins
KRAFL, Jaroslav
Mobility of pigment-protein complexes (phycobilizomes and photosystem II playing a key role in photosynthesis) was studied by FRAP method (Fluorescence Recovery After Photobleaching). FRAP represents a fluorescence based microscopy method enabling measurement of protein mobility in living systems. The protein complexes are bleached by a laser pulse. And mobility of unbleached proteins is measured as a fluorescence recovery in the bleached area. Currently we have only limited knowledge about the mobility of photosynthetic proteins. This work was aimed at optimization of the photosynthetic protein mobility measurement by FRAP. I have performed several methodological experiments which led to the successful assessment of phycobilisome and chlorophyll-containing proteins diffusion coefficients in selected red algae (Porfyridium cruentum, Cyanidium caldarium) and cyanobacteria (Synechocystis PCC6803, Acaryochloris marina). The methodology developed and validated in my thesis was then applied in further research projects.
Photosynthesis, production and growth of plants under temporal light hererogeneity
KUBÁSEK, Jiří
In this Ph.D. thesis I am dealing with the effect of dynamic irradiance on (i) photosynthesis, growth and bundle sheath leakiness (for CO2) of C4 plants and (ii) bryophyte photosynthesis. Part of this thesis is literature review on broader aspects of the dynamic light effects on photosynthetic and growth processes in plants.
Respiration of zooplankton in eutrophic ponds
LENDLEROVÁ, Lucie
Respiration in ponds recycles organic carbon arising from photosynthesis back to inorganic carbon. Zooplankton is most important in the process of respiration in the pond. Prior to this transformation, the organic carbon is potentially available to support secondary production. The efficiency of primary and secondary production relative to respiration is an important feature of ponds and other aquatic ecosystems. Intensive respiration in sediments often leads to oxygen depletion and even anoxia. Thus, the rates and controls of respiration are of central importance in pond ecosys-tems. The results show that zooplankton respiration make 60% or more of system respiration in the spring stage of clean water. There may be situations when it is pos-sible increase of benthic filamentous algae thanks to high transparency. Their photo-synthetic assimilation effectively balances oxygen deficit caused by zooplankton respiration and not occur dangerous deficit situations for fish which are usual in this period.

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