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LED technology for Lighting Plants
Pospíšil, Tomáš ; Pavelka, Tomáš (referee) ; Krbal, Michal (advisor)
The aim of the work is to describe the physiology of plants and their needs to the successful evolution and growth. Furthermore to introduce a characteristic light requirement of plants and summarize differences between light requirements of the human eye and plants. More there are shortly mentioned the light quantities and units and by means of these quantities and their units there is assessed the appropriateness of lighting for plants. Another aim is to describe the electric and lighting-technical LED parameters that are suitable for use as a lamp designed for illumination of plants, outline the basic requirements that should the lamp designed for illuminating the plants fulfill. The last part is devoted to the presentation and evaluation of the measurement results of the lamp, which was already developed and used on prototype light source using LED.
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Spectrophotometric determination of chlorophyll
Rábová, Petra ; Vavrčíková, Veronika (referee) ; Řezáčová, Veronika (advisor)
This bachelor thesis is focused on determination of chlorophyll in leaves by the method of extraction spectrophotometry. The theoretical part provides information about photosynthesis, stress factors or plant adaptation, photosynthetic pigments (especially chlorophyll-a) and application of spectrophotometry and other methods of chlorophyll determination. The experimental part is focused on the application of the ecotoxicological test and, above all, it is evaluation by two independent methods. Specifically, it was determination of biomass growth inhibition and newly spectrophotometrical determination of chlorophyll mass. The results correlate with each other, therefore, the determination of chlorophyll seems to be an appropriate extension of usual evaluation methods of ecological tests.
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The impact of UV radiation on activity and content of Rubisco enzyme in beech
Cigánková, Michaela ; Urban,, Otmar (referee) ; Hrstka, Miroslav (advisor)
This bachelor thesis deals with the influence of UV radiation on content and activity of Rubisco enzyme in leaves of European beech (Fagus sylvatica). Plants were cultivated in ambient (UV), lower (UV-) and higher (UV+) UV-B radiation both at ambient (AC) and elevated (EC = 700 micromol mol-1) CO2 concentrations. Leaves sampling was done four times during the growth season, in the second part of July, at the beginning and in the end of August and in the middle of September. Rubisco activity was assayed spectrophotometrically, the content of Rubisco was determined by SDS-PAGE method and quantified by computer densitometry. The results confirmed a reduction of Rubisco content and down-regulation on Rubisco level at elevated CO2 concentration. With the exception of September sampling, the content of Rubisco was lower in UV+ at ambient concentration of CO2. The same was not demonstrated at elevated CO2 conditions. Hypothesis that UV-B radiation changes a ratio of large to small subunit of Rubisco was confirmed. The influence of UV-B radiation on Rubisco activity was not proved.
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Plants polysaccharides and their importance in food production
Klanicová, Barbora ; Illková, Kateřina (referee) ; Omelková, Jiřina (advisor)
Some findings about plant polysaccharides, their characteristics and structures, modifications, changes, their biosynthases, isolationes and primarily their importance in food-stuff industry are the subject matter of this review. Because of their modifications and because of the significant role they play in food-processing industry it is focused on starch and cellulose. For better understanding of whole meaning it was necessary to attend to the theme from the initiation – mainly the cell structure and then syntheses, especially photosynthesis, ways that are monosaccharides and polysaccharides generated.
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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.
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The dynamics of non-structural saccharides accumulation and Rubisco activity under the elevated carbon dioxide concentration and sink manipulation at beech
Uhrová, Lucie ; Vítová, Eva (referee) ; Hrstka, Miroslav (advisor)
This diploma thesis deals with dynamic of accumulation of non-structural carbohydrates and activity of Rubisco enzyme at elevated concentration of CO2 on beech (Fagus sylvatica L.). Three years old seedlings of beech were cultivated in minisphere with ambient (385 µmol•mol-1, variant A), and with elevated concentration CO2 (700 µmol•mol-1, variant E) for four months. In every variant the first half of plants was fertilized by nitrogen (variant N+) and the second half was control (variant N-). Plants used for experiment were at first adapted for darkness for 12 hours. Subsequently tested leaves were cut off, leafstalk including short segment of branch (approximately 1 cm) was inserted into 0.7 M solution of sucrose (variant S) or water (variant V) and exposed to radiation 200 mol•m-2•s-1 for 0, 30, 60, 120, 180 minutes. Then leaf area and fresh mass of leaf blade were established, samples were fixed in liquid nitrogen and stored in deep freezer to analysis in –70 °C. Rubisco content was determined by SDS-PAGE method, Rubisco activity spectrofotometrically and content of non-structural carbohydrates by anthrone method and HPLC method. Rubisco content was significantly lower in the N- variant than in N+ variant. Rubisco content was also significantly lower in E than in A variant, which is an evidence of down-regulation. Rubisco activity is moderately stimulated at E variant with time, but differences between variant A and E are not statistically significant. Influence of sucrose feeding to Rubisco activity was not proved. Significant differences were detected by anthrone method in non-structural carbohydrates content between variants S and V, but not between variants A and E. Statistically significant increase of sucrose content with time was detected by HPLC method at variant AS, but not at variant ES.
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Strukturně funkční charakteristika průduchů jmelí bílého (Viscum album L.) a jeho hostitele lípy (Tilia sp.)
Bělíček, Dominik
This thesis deals with a comparison of the morphology of the stomata of the hemiparasite European mistletoe (Viscum album L.) and its host lime tree (Tilia sp.) in the context of physiological parameters such as water potential, stomatal conductance, and photosynthesis, in order to understand the relationship between the two species. The research was carried out at the Ústřední hřbitov in Brno. Here, 10 infested and 10 uninfested lime trees were selected. During the summer of 2022, varnish impressions were taken from the leaves of lime and mistletoe trees and then all physiological parameters were measured. It was found that mistletoe infestation had almost no significant effect on both the morphology and physiology of lime tree leaves. Furthermore, it was shown that mistletoe has more smaller stomata than linden. It has been shown that although mistletoe has a higher stomatal conductance, the photosynthetic rate is the same for both species, thus the water use efficiency of mistletoe is much lower. It was confirmed that mistletoe, as a hemiparasite, has a much lower water potential than the host. Although this information helps to understand this interrelationship, it also results in further uncertainties worth to investigate in future.
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Vliv nízké teploty na propustnost buněčných membrán a přežití rostlin
Kubovčíková, Anna
Plants are naturally exposed to low temperatures in nature. During the winter, the temperatures are the lowest and in certain places they even reach very low values. Jasmonic acid plays an important role in the plant's resistance to low temperatures. In the thesis, we have focused on the effect of the PLIP genes that produce precursors of jasmonic acid. The role of the genes in cold resistance in Arabidopsis thaliana was studied after acclimation in different light conditions. The observed parameters in plants acclimated to low temperatures were the parameters of photosynthesis, intactness of cell membranes and survival after exposure to freezing. The results of the experiments proved that the mutation of the PLIP genes cause a decrease in the integrity of the cell membranes when exposed to freezing, and conversely, the ectopically increased expression of the PLIP3 gene results in an increase in plant resistance. Based on ion leakage, we determined LT50 values for each variant, and it was shown that the difference between the most resistant transgenic line plip3 ox and the mutant line in all three PLIP genes is more than 4 °C. Subsequently, a plant survival test after freezing was performed, where it was demonstrated that the LT50 value correlated with plant survival. Chlorophyll fluorescence analysis showed that after acclimation to low temperature, there are no large differences in photosynthetic parameters between individual genotypes with modified PLIP level. The light that was applicated during acclimation had a more pronounced effect on the plants. Plants acclimated at low intensity showed higher values of non-photochemical quenching as well as greater maximum quantum yield of photosystem II. The results prove that the PLIP genes are significantly involved in the resistance of plants to low temperatures.
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Vliv světla na fotosyntézu bylin v podrostu doubrav
Zvyniatskovskyi, Yan
The forest environment is increasingly changing. Climate change brings along not only changed macroclimate. Stand microclimate is changing as well due to changes in tree species composition and the natural reduction in tree cover because of increased mortality. Understory herbs are sensitive to changes in the tree canopy cover. In sparse stands, more light reaches the understory compared to dense stands. Different understory herb species have different ability to use light and adapt to changing conditions. Short-term changes in their photosynthesis lead to long-term changes in species composition and their abundance. This bachelor thesis investigated the effect of different light availability on the photosynthetic parameters of understory herbs. I compared 8 taxa from four groups of Ellenberg ecological indicator values (EIV). The research was carried out in a stand of thermophilous oak-hornbeam in the Pálava Protected Landscape Area (PLA), on plots with different levels of tree canopy thinning. Herbs growing under fully stemmed stands plastically reduced respiration compared to herbs in the thinned forest, which allowed them to survive even under dense forest cover. However, they were still able to achieve high rates of photosynthesis under full illumination for short periods of time, i.e., they actively utilized short episodes of direct sunlight. Species characterized by EIH as shade-loving respired less in the dark than species with higher EIH in relation to light, suggesting a link between light availability and long-term abundance of herbaceous taxa. The results of this study suggest how the herbaceous understory of temperate forests might change in the context of climate change, with potential implications for forest typology.
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Teaching the Topic of Photosynthesis using Aspects of Inquiry-based Learning
Rapantová, Lenka ; Vojíř, Karel (advisor) ; Nejedlý, Adam (referee)
This bachelor thesis deals with the teaching of photosynthesis in primary school science classes. The aim of the thesis was to validate a teaching program with elements of inquiry- oriented teaching, to find out its effectiveness on the level of knowledge acquired by the pupils of the seventh year at the second grade of the primary school. To investigate the educational effect, an initial pre-test was designed to ascertain the pupils' prior knowledge. Furthermore, the knowledge acquired after the laboratory tasks were carried out was analyzed and verified by an analogous post-test. The premise was that the laboratory activity would motivate the pupils' interest in science and provide a better understanding of photosynthesis, especially its inputs, waste substances and products. Another aim of this thesis was to find out how pupils perceive the attractiveness, value and usefulness of the tutorial after completing it and how they evaluate their efforts in this type of learning. A standardized IMI (Intrinsic Motivation Inventory) questionnaire survey was used to determine the above. The paper describes in detail the different laboratory tasks that were part of the curriculum applied in science classes, as well as the procedures necessary for their implementation and the students' reactions to the...
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