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Yield formation parameters of winter wheat under two CO2 levels in water sufficient and depleted environment
Hlaváčová, Marcela ; Klem, Karel ; Veselá, Barbora ; Findurová, Hana ; Hlavinka, Petr ; Smutná, P. ; Horáková, V. ; Škarpa, P. ; Trnka, Miroslav
Agricultural production faces with ongoing climate that in Europe takes form of changing seasonal precipitation pattern with more frequent drought spells. These changes come on top of rising air temperature and did and will affect productivity as well as onset and duration of key developmental stages for yield formation of major staple crops such as wheat. In order to ensure stable agricultural production and satisfy demand of the increasing humanpopulation, it is crucial to know responses of major field crops to these abiotic stress factors to assess suitability of genotypes to specific environmental conditions. The aim of this study was to evaluate final yield formation parameters of five winter wheat genotypes cultivated in pots and exposed to two different levels of CO2 concentrations (400 ppm as ambient and 700 ppm as elevated CO2 concentrations) and two water treatments (well- watered control and drought-stressed plants). Theexperimental treatments were set up in growth chambers from the end of heading stage (BBCH 59)to the beginning of ripening stage (BBCH 71) to simulate the conditions under future climate. The results showed that elevated CO2 concentration led to: (1) mitigation of reduction in final yield formation parameters of drought-stressed plants compared to those of control, (2) enhanced results of drought-stressed treatments compared to those of drought-stressed treatments exposed to the ambient CO2 concentration. Pannonia NS was found out as the less responsive genotype to the exposition of CO2 concentration (no statistically significant differences among ambient and elevated CO2 concentrations in all yield formation parameters were identified). On contrary, harvest index of genotype Bohemia was identified as the most sensitive parameter in response to drought stress as well as to the atmospheric CO2 concentration.
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Anatomical study of shade and sun European beech leaf under elevated CO2.
Horská, Jana ; Lhotáková, Zuzana (advisor) ; Urban, Otmar (referee)
The present Master thesis focuses on evalution of CO2 concentration and irradiance on selected leaf anatomical parameters of European Beech (Common Beech) Fagus sylvatica L.. The process of photosynthesis is remarkably determined by numerous extrenal factors, among them by atmoshperic CO2 concentration and irradiance and is closely correlated with leaf anatomical parameters. One of these most important anatomical parameters affecting the net assimilation rate is an internal leaf surface, which corresponds to mesophyll area avialable for gas exhcange. Experimental material of the study was sampled from the leaves of juvenile trees of F. sylvatica planted in 2005 and growing under ambient (390 ppm, AC) and elevated (700 ppm, EC) CO2 concentrations on the experimental site of the Global Change Research Center AS CR at Bílý Kříž in the Beskydy Mountains. Sun and shade leaves were sampled from trees of both CO2 treatments in two seasons 3 years apart (2009 and 2012). To determine leaf anatomical parameters, the stereological methods were applied, which yield unbiased estimation of measured parameters, particularly the Fakir method for internal leaf surface determination. The EC effect was observed on the leaves sampled in 2009 only in the decrease of proportion of intercellular spaces in mesophyll. In...
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Anatomical study of shade and sun European beech leaf under elevated CO2.
Horská, Jana ; Lhotáková, Zuzana (advisor) ; Urban, Otmar (referee)
The present Master thesis focuses on evalution of CO2 concentration and irradiance on selected leaf anatomical parameters of European Beech (Common Beech) Fagus sylvatica L.. The process of photosynthesis is remarkably determined by numerous extrenal factors, among them by atmoshperic CO2 concentration and irradiance and is closely correlated with leaf anatomical parameters. One of these most important anatomical parameters affecting the net assimilation rate is an internal leaf surface, which corresponds to mesophyll area avialable for gas exhcange. Experimental material of the study was sampled from the leaves of juvenile trees of F. sylvatica planted in 2005 and growing under ambient (390 ppm, AC) and elevated (700 ppm, EC) CO2 concentrations on the experimental site of the Global Change Research Center AS CR at Bílý Kříž in the Beskydy Mountains. Sun and shade leaves were sampled from trees of both CO2 treatments in two seasons 3 years apart (2009 and 2012). To determine leaf anatomical parameters, the stereological methods were applied, which yield unbiased estimation of measured parameters, particularly the Fakir method for internal leaf surface determination. The EC effect was observed on the leaves sampled in 2009 only in the decrease of proportion of intercellular spaces in mesophyll. In...
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The effect of elevated CO2 concentration and irradiation on quantitative parameters of mesophyll cells of Norway spruce
Kubínová, Zuzana ; Albrechtová, Jana (advisor) ; Radochová, Barbora (referee)
KUBÍNOVÁ, Zuzana. The effect of elevated CO2 concentration and irradiation on quantitative parameters of mesophyll cells of Norway spruce. Prague, 2010. 74 p. Master's degree thesis. Faculty of Science, Charles University in Prague. Abstract The aim of the present thesis was to choose and adjust a suitable methodology for counting particles in 3D space, which would be suitable for unbiased estimation of chloroplast number in needle mesophyll cells. The disector method was used for the first time to determine the number of chloroplasts. This method enables unbiased estimation of chloroplast number in needle volume from optical sections captured from fresh free-hand sections by confocal microscope. The sections did not need any pre-processing. Another aim was to compare selected photosynthetic and anatomical characteristics of sun and shade Norway spruce needles, which were grown under different CO2 concentration. The trees were grown for eight years in ambient (during the experiment increasing from 357 up to 370 µmol CO2 ∙ mol-1 ) CO2 concentration or elevated (700 µmol ∙ mol-1 ) CO2 concentration in special glass domes on an experimental research site of the Institute of Systems Biology and Ecology, Academy of Sciences of the Czech Republic at Bílý Kříž in Moravskoslezské Beskydy mountains. The sun needles...
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Changes in the photosynthetic apparatus of european beech and Norway spruce under long-term exposure to elevated CO2
Holišová, Petra ; Šprtová, Miroslava ; Kubásek, Jiří ; Lhotáková, Z. ; Mašková, P. ; Lipavská, H. ; Kočová, M. ; Holá, D. ; Radochová, Barbora ; Albrechtová, J. ; Urban, Otmar
The changes of photosynthetic performance caused by increasing CO2 concentration are refl ected at diff erent hierarchical levels of photosynthetic apparatus from the effi ciency of individual photosynthetic processes to changes in leaf structure. Th e aim of this study was to elucidate the relationships between the ultrastructure and function of photosynthetic apparatus under elevated CO2 concentration. We studied two common tree species – the European beech and the Norway spruce – grown under ambient (AC) and elevated CO2 concentrations (EC). Photosynthetic parameters were obtained using the gas-exchange system LI-6400 (LI-COR, USA). Th e characteristics of chlorophyll a fl uorescence were obtained in vivo with FluorPen FP100max (PSI, CZE) and in vitro polarographically in a suspension of isolated chloroplasts. Non-structural soluble saccharides and starch accumulation was quantifi ed using HPLC. Th e chloroplast ultrastructure was quantifi ed by stereological methods (Ellipse 2.08, SK) on the images acquired on a JEOL JEM-1011 (JEOL, JPN). Th e light-saturated CO2 assimilation rate was stimulated by EC in both species. Th e assimilation capacity of EC plants slightly decreased and was accompanied by a slight decrease in the rate of electron transport and the rate of Rubisco carboxylation. Th e growth in EC induced higher energy dissipation by light-harvesting antennae, diminished PSII activity, resulted in greater PSI capacity and in higher accumulation of starch and soluble sugars in the leaves of both species.
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The effect of elevated air CO2 concentration on water regime and transpiration of Norway spruce
Valouch, Ludvík ; Pokorný, Radek ; Tomášková, Ivana
Under the elevated CO2 air concentration, changes in physiological processes and morphology were evident in relatively short time. Direct measurement via heat pulse method proved reduction of specific sap flux throw the stem in the first year of cultivation in elevated CO2. SSF in both treatments was comparable in the next tree years. During the sixth year of fumigation, higher transpiration rate in trees growing under elevated CO2 was recorded. It was implication of larger bearing leaf area, larger conducting vessels area on the in crosscut stems section and larger root absorbed area. Continuously sap flow measuring of sun and shaded part of the crown was found that SSF of higher crown part was higher in both treatments. Average hydraulic conductance soil-leaf (GTsa) was 1,4 times higher in sunny part of the crown than estimated for the whole crown in ambient treatment A (ambient [CO2] concentration). Difference in hydraulic conductance between the upper and lower crown part of the E treatment (doubled [CO2] concentration of A treatment) was not so pronounced.
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