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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Vliv minerálního hnojení na fotosyntetické charakteristiky ostřice štíhlé (Carex acuta) / Effect of mineral fertilization on photosynthetic characteristics of Carex acuta

LESKOVCOVÁ, Martina January 2009 (has links)
The MSc. thesis "Effect of mineral fertilization on photosynthetic characteristics of Carex acuta" deals with photosynthetic characteristics of plants subjected to different nutrient regimes. Stands dominated with Carex acuta were studied din two localities: Záblatské louky with organic soil and Hamr with mineral soil. The experimental treament was subjected to high fertilization, while the control treatment received no nutrient addition. The net assimilation was measured using Licor 6400. The aim was to find out whether the net assimilation was higher in fertilized plants as compared with non-fertilized plants. In spring the fertilized plants did not have higher photosynthetic rates at either locality, probably because of water limitation. The positive effect of fertilization was proved only at Hamerské louky after the second cut.
12

Mobilita fotosyntetických proteinů / Mobility of photosynthetic proteins

KRAFL, Jaroslav January 2014 (has links)
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.
13

Mechanism of photoprotection in photosynthetic proteins / Mechanism of photoprotection in photosynthetic proteins

TRSKOVÁ, Eliška January 2015 (has links)
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.
14

Rostliny a atmosféra - didaktické zpracování tématu pro výuku na základní škole / Plants and atmosphere - didactic processing of the theme for teaching on the elementary school

ČEKAL, Tomáš January 2016 (has links)
The aim of this work was to process the selected theme of the fields of relationships between plants and atmosphere by means of learning programme based on the inquiry approach didacticly and apply it at the elementary school. The aim of the thesis was also to investigate the influence of the created learning programme on the level of pupils´ knowledge. 150 pupils took part in this testing. The research approved that by means of using IBE (Inquiry based education) the level of pupils´ knowledge compared with the frontal form of the education is increasing. The next fact was that pupils´ knowledge of photosynthesis was only on the average. It was also confirmed that with the using of this learning programme with the elements of exploration and the use of modern technology (pupils´ sets called Vernier) the curriculum was absorbed by students more efficiently.
15

Závislost obsahu chlorofylu v listnatých dřevinách na znečištění prostředí / Chlorophylle content relationship to environment pollution in broad leaved trees

KLEINOVÁ, Miroslava January 2014 (has links)
The purpose of this work was the establishment of the amount of chlorophyll in diverse species of deciduous trees in enviroment contaminated by road transport. To determine this, the tests were made from may to august on the leaves of a smallleaved lime tree (Tilia cordata) and sycamore tree (Platanus occidentalis).
16

Vliv 24-epibrassinolidu na vybrané parametry genotypů kukuřice a bobu lišících se citlivostí k suchu / The effect of 24-epibrassinolide on selected parameters of maize and faba bean genotypes varying in drought sensitivity

Řehořová, Kateřina January 2015 (has links)
Brassinosteroids are plant hormones which are also known for their pleiotropic effects on plants exposed to various biotic and abiotic stress factors. The aim of this study was to evaluate the role of 10-8 M 24-epibrassinolide in Zea mays L. and Vicia faba L., grown under conditions of drought stress (6, 10, 14, 18 days) with an emphasis on different answer to their drought sensitive and resistant genotypes. Net photosynthetic rate (PN) and transpiration rate (E), stomatal conductance (gs), osmotic potential (ψs), proline (Pro) and malondialdehyde (MDA) content and membrane injury index (MI) were measured in stressed plants and plants grown under controlled conditions. The most important factor influencing these parameters was drought, which led to a gradual decrease of PN, E, gs, ψs and increase of Pro, MDA a MI. The effect of 24-epibrassinolid was significant rather exceptionally and in these cases, more pronounced response was observed in drought stressed plants compared with plants grown under controlled conditions. Plants showed intraspecific variability in their reactions, which in sensitive and tolerant genotypes were not clear and differed depending on the studied parameters and conditions of plant cultivation.
17

Úloha chloroplastů ve středním válci kořenů epifytických orchidejí / The role of chloroplasts in the stele of epiphytic orchid roots

Ungrová, Anna January 2021 (has links)
The photosynthesis of the aerial roots of epiphytic orchids has been the subject of numerous studies. However, the roots are always evaluated as a homogeneous structure, even though they actually consist of significantly different areas. This work deals for the first time with the possibility of the spatial distribution of photosynthesis between the root layers, specifically the cortex and the stele. A combination of various microscopic techniques, the histochemical characterization of the apoplastic barriers and the immunohistochemical localization of the photosynthetic enzyme phosphoenolpyruvate carboxylase has been used. The results show that well-developed chloroplasts in the stele probably occur in the subfamily Epidendroideae in all epiphytic representatives, while in the subfamily Vanilloideae they occur occasionally. The ultrastructure of chloroplasts from both areas is systematically different, so it is likely that their functions also differ. Apoplastic barriers are prominent in the roots and differentiate early during root development, which can effectively isolate chloroplasts in the stele from the cortex. Chloroplasts also occur in the sclerenchyma cells of the stele, where were identified hitherto unknown pits in cell walls that could provide gas exchange within the stele....
18

Fotosyntéza, produkce a růst rostlin při časově proměnné ozářenosti / Photosynthesis, production and growth of plants under temporal light hererogeneity

KUBÁSEK, Jiří January 2014 (has links)
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.
19

Analýza antioxidačních systémů, morfologických a fyziologických parametrů u dvou odrůd bobu (Vicia faba L.) během stresu suchem / Analysis of antioxidant systems, morphological and physiological parameters in two faba bean (Vicia faba L.) cultivars during drought stress

Jelénková, Iva January 2013 (has links)
Knowledge of physiological and morfological mechanisms which are related to drought tolerance is essential in breeding high-yielding and tolerant plants, which would not suffer unfavourable environmental conditions. Drought stress can lead to oxidative damage which causes serious disorders in physiological and biochemical processes in plant cells. Antioxidants can reduce those negative effects. Morphological (dry mass of shoot and roots, height of shoot, number of leaves), physiological (photosynthetic efficiency, pigment content, relative water content-RWC) and antioxidative (catalase-CAT, ascorbate peroxidase-APX, proline) parameters were evaluated in this study using two genotypes of Vicia faba L. differing in drought susceptibility. Drought resistant (Merkur) and sensitive (Piešťanský) genotypes were exposed to 10 days of drought. Activity of CAT and APX of stressed plants rather decreased. Proline content oscillated and no evident trend or significant differences were observed in relation to drought stress. Decrease in RWC was expressed more at susceptible plants, electron-transport chain activity and pigment content were not affected much by drought. Drought susceptible genotype expressed more serious negative effects of drought in morphological parameters, however this genotype was a bit bigger than...
20

Structure and function of pigment-protein complexes of photosynthetic microorganisms / Structure and function of pigment-protein complexes of photosynthetic microorganisms

HERBSTOVÁ, Miroslava January 2010 (has links)
Biochemical and biophysical methods in combination with electron microscopy were used to investigate structure and function of pigment-protein complexes in thylakoid membranes of various photosynthetic organisms.

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