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2. Comparative studies of compatible and incompatible pepper-Tobamovirus interactions and the evaluation of effects of 24-epibrassinolide
- Creator:
- Janeczko, A., Dziurka, M., Gullner, G., Kocurek, M., Rys, M., Saja, D., Skoczowski, A., Tóbiás, I., Kornas, A., and Barna, B.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- brassinosteroidy, brassinosteroids, CO2 asimilace, xantofylový cyklus, CO2 assimilation, systemic virus response, water band index, xanthophyll cycle, 2, and 581
- Language:
- Multiple languages
- Description:
- The aim of study was to gain a deeper knowledge about local and systemic changes in photosynthetic processes and sugar production of pepper infected by Obuda pepper virus (ObPV) and Pepper mild mottle virus (PMMoV). PSII efficiency, reflectance, and gas exchange were measured 48 and/or 72 h after inoculation (hpi). Sugar accumulation was checked 72 hpi and 20 d after inoculation (as a systemic response). Inoculation of leaves with ObPV led to appearance of hypersensitive necrotic lesions (incompatible interaction), while PMMoV caused no visible symptoms (compatible interaction). ObPV (but not PMMoV) lowered Fv/Fm (from 0.827 to 0.148 at 72 hpi). Net photosynthesis decreased in ObPV-infected leaves. In ObPV-inoculated leaves, the accumulation of glucose, fructose, and glucose-6-phosphate was accompanied with lowered sucrose, maltoheptose, nystose, and trehalose contents. PMMoV inoculation increased the contents of glucose, maltose, and raffinose in the inoculated leaves, while glucose-6-phosphate accummulated in upper leaves., A. Janeczko, M. Dziurka, G. Gullner, M. Kocurek, M. Rys, D. Saja, A. Skoczowski, I. Tóbiás, A. Kornas, B. Barna., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
3. Effects of root temperature on leaf gas exchange and xylem sap abscisic acid concentrations in six Cucurbitaceae species
- Creator:
- Zhang, Y. P., Qiao, Y. X., Zhang, Y. L., Zhou, Y. H., and Yu, J. Q.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- adaptation, CO2 assimilation, photosystem 2 photochemistry, photosynthesis, and stomatal behaviour
- Language:
- Multiple languages
- Description:
- Roots of six Cucurbitaceae species were exposed to low (14 °C), middle (24 °C), and high (34 °C) temperatures while aerial parts of plants were maintained at ambient temperatures between 23 and 33 °C. The highest dry mass (DM), photon-saturated rate of net photosynthesis (PNsat), and stomatal conductance (gs) were found at 14 °C in figleaf gourd and turban squash plants, at 24 °C in cucumber and melon plants, while bitter melon and wax gourd plants had lower DM, PNsat, and gs at 14 °C than at 24 or 34 °C. Sub-or supra-optimum root temperatures did not induce photoinhibition but induced slight changes in the quantum efficiency of photosystem 2, PS2 (ΦPS2) and photochemical quenching (qp). Meanwhile, xylem sap abscisic acid (ABA) concentration followed a contrasting change pattern to that of gs. Thus the change in PNsat was mainly due to the change in gs and roots played an important role in the regulation of stomatal behaviour by delivering increased amount of ABA to shoots at sub-or supra-optimum root temperatures. and Y. P. Zhang ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
4. Gas-exchange parameters and morphological features of festulolium (Festulolium braunii K. Richert A. Camus) in response to nitrogen dosage
- Creator:
- Mastalerczuk, G., Borawska-Jarmułowicz, B., Kalaji, H. M., Dąbrowski, P., and Paderewski, J.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- dusík, morfologie (biologie), nitrogen, morphology (biology), asimilace CO2, průměr kořene, specifická délka kořene, výměna plynu, festulolium, CO2 assimilation, root diameter, specific root length, gas exchange, 2, and 581
- Language:
- Multiple languages
- Description:
- The response of some photosynthetic parameters (CO2 assimilation, transpiration rate, stomatal conductance, intercellular CO2 concentration, water-use efficiency, and chlorophyll content), shoot development, and the morphological features of the root system to differentiated conditions of nitrogen supply was tested in festulolium (Festulolium braunii K. Richert A. Camus) varieties (Felopa and Sulino). Nitrogen fertilization with no nitrogen added [0 g(N)], single dosage [0.23 g(N)], and double dosage [0.46 g(N)] per pot and per year was applied. Lack of nitrogen resulted in formation of longer and finer roots and lowered chlorophyll content, CO₂ assimilation, and water-use efficiency, resulting in lower dry matter accumulation. Application of both dosages of nitrogen resulted in improved aboveground features, while root features were enhanced without nitrogen fertilization. Dependence between physiological parameters and morphological traits was significant and positively correlated in the case of the aboveground parts of plants and negatively correlated to the belowground parts., G. Mastalerczuk, B. Borawska-Jarmułowicz, H. M. Kalaji, P. Dąbrowski, J. Paderewski., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
5. Mechanical wounding caused by inoculation influences the photosynthetic response of Nicotiana benthamiana plants to plum pox potyvirus
- Creator:
- Hlaváčková, V., Špundová, M., Nauš, J., Navrátil, M., Kouřil, R., and Kaňa, R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- chlorophyll fluorescence, CO2 assimilation, ELISA-DASI, systemic response, net photosynthetic rate, thermoluminescence, tobacco, and viral infection
- Language:
- Multiple languages
- Description:
- Plants of Nicotiana benthamiana (Gray) (60 d old) were mechanically inoculated by a spreading of the fourth and fifth leaves with inoculum with or without plum pox potyvirus (PPV). Changes in growth parameters and selected photosynthetic characteristics were followed in control and inoculated plants in the locally affected leaves (LA) during 11 d after inoculation (DAI), in systemically affected leaves immature at time of inoculation (SAI) during 14-25 DAI, and in systemically affected leaves developed after the inoculation (SAD) during 28-39 DAI. The pure mechanical damage caused by inoculation induced a decrease in the net photosynthetic rate (PN) in LA and SAD leaves, and an increase in the steady-state value of the non-photochemical chlorophyll (Chl) fluorescence quenching qN. The qN increase appeared in certain time intervals in all measured leaves on plants, so it could be regarded as indication of a systemic reaction of plant to the local mechanical injury. The viral infection developed in LA leaves and spread to SAI and SAD leaves was documented by the ELISA-DASI method. The plant height and area of SAI and SAD leaves were lower in infected plants. The combined effect of mechanical damage and viral infection caused a decrease in PN only in LA and SAD leaves. In SAD leaves, an increased relative height of the J step (VJ) in the O-J-I-P Chl fluorescence transient together with a lower B/A band ratio of thermoluminescence glow curves reflected a damage to the acceptor side of photosystem 2 (PS2) caused by the viral infection, and a faster kinetics of the induction of the photochemical quenching coefficient qP of Chl fluorescence indicated a faster QA- re-oxidation in the remaining undamaged centres of PS2. and V. Hlaváčková ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
6. Plant shading increases lipid peroxidation and intensifies senescence-induced changes in photosynthesis and activities of ascorbate peroxidase and glutathione reductase in wheat
- Creator:
- Špundová, M., Slouková, K., Hunková, M., and Nauš, J.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- ageing, chlorophyll fluorescence, CO2 assimilation, plant topography, and Triticum aestivum
- Language:
- Multiple languages
- Description:
- Plants of spring wheat (Triticum aestivum L. cv. Saxana) were grown during the autumn. Over the growth phase of three leaves (37 d after sowing), some of the plants were shaded and the plants were grown at 100 (control without shading), 70, and 40 % photosynthetically active radiation. Over 12 d, chlorophyll (Chl) and total protein (TP) contents, rate of CO2 assimilation (PN), maximal efficiency of photosystem 2 photochemistry (FV/FP), level of lipid peroxidation, and activities of antioxidative enzymes ascorbate peroxidase (APX) and glutathione reductase (GR) were followed in the 1st, 2nd, and 3rd leaves (counted according to their emergence). In un-shaded plants, the Chl and TP contents, PN, and FV/FP decreased during plant ageing. Further, lipid peroxidation increased, while the APX and GR activities related to the fresh mass (FM) decreased. The APX activity related to the TP content increased in the 3rd leaves. The plant shading accelerated senescence including the increase in lipid peroxidation especially in the 1st leaves and intensified the changes in APX and GR activities. We suggest that in the 2nd and 3rd leaves a degradation of APX was slowed down, which could reflect a tendency to maintain the antioxidant protection in chloroplasts of these leaves. and M. Špundová ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
7. Role of fructose-1,6-bisphosphatase, fructose phosphotransferase, and phosphofructokinase in saccharide metabolism of four C3 grassland species under elevated CO2
- Creator:
- Nádas, E., Balogh, Á. , Kiss, F., Szente, K., Nagy, Z., Martínez-Carrasco, R., and Tuba, Z.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- acclimation, CO2 assimilation, fructose-1,6-bisphosphatase, gluconeogenesis, glucose-6-phosphate dehydrogenase, glycolysis, oxidative pentose phosphate pathway, phosphofructokinase, pyrophosphate D-fructose-6-phosphate l-phosphotransferase, and starch
- Language:
- Multiple languages
- Description:
- We studied the effects of 15-months of elevated (700 µmol mol-1) CO2 concentration (EC) on the CO2 assimilation rate, saccharide content, and the activity of key enzymes in the regulation of saccharide metabolism (glycolysis and gluconeogenesis) of four C3 perennial temperate grassland species, the dicots Filipendula vulgaris and Salvia nemorosa and the monocots Festuca rupicola and Dactylis glomerata. The acclimation of photosynthesis to EC was downward in F. rupicola and D. glomerata whereas it was upward in F. vulgaris and S. nemorosa. At EC, F. rupicola and F. vulgaris leaves accumulated starch while soluble sugar contents were higher in F. vulgaris and D. glomerata. EC decreased pyrophosphate-D-fructose-6-phosphate l-phosphotransferase (PFP, EC 2.7.1.90) activity assayed with Fru-2,6-P2 in F. vulgaris and D. glomerata and increased it in F. rupicola and S. nemorosa. Growth in EC decreased phosphofructokinase (PFK, EC 2.7.1.11) activity in all four species, the decrease being smallest in S. nemorosa and greatest in F. rupicola. With Fru-2,6-P2 in the assay medium, EC increased the PFP/PFK ratio, except in F. vulgaris. Cytosolic fructose-1,6-bisphosphatase (Fru-1,6-P2ase, EC 3.1.3.11) was inhibited by EC, the effect being greatest in F. vulgaris and smallest in F. rupicola. Glucose-6-phosphate dehydrogenase (G6PDH EC 1.1.1.49) activity was decreased by growth EC in the four species. Activity ratios of Fru-1,6-P2ase to PFP and PFK suggest that EC may shift sugar metabolism towards glycolysis in the dicots. and E. Nádas ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
8. Seasonal changes of selected parameters of CO2 fixation biochemistry of Norway spruce under the long-term impact of elevated CO2
- Creator:
- Urban, O. and Marek, M. V.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- acclimation depression, carbon sink, CO2 assimilation, elevated CO2 concentration, electron transport, Picea abies, and ribulose-1,5-bisphosphate carboxylase/oxygenase
- Language:
- Multiple languages
- Description:
- Twelve-year-old Norway spruce (Picea abies [L.] Karst.) trees were exposed to ambient (AC) or elevated (EC) [ambient + 350 µmol(CO2) mol-1] CO2 concentrations in open-top-chamber (OTC) experiment under the field conditions of a mountain stand. Short-term (4 weeks, beginning of the vegetation season) and long-term (4 growing seasons, end of the vegetation season) effects of this treatment on biochemical parameters of CO2 assimilation were evaluated. A combination of gas exchange, fluorescence of chlorophyll a, and application of a mathematical model of ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBPCO) activity was used. The analysis showed that the depression of photosynthetic activity by long-term impact of elevated CO2 was mainly caused by decreased RuBPCO carboxylation rate. The electron transport rate as well as the rate of ribulose-1,5-bisphosphate (RuBP) formation were also modified. These modifications to photosynthetic assimilation depended on time during the growing season. Changes in the spring were caused mainly by local deficiency of nitrogen in the assimilating tissue. However, the strong depression of assimilation observed in the autumn months was the result of insufficient carbon sink capacity. and O. Urban, M. V. Marek.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
9. Seasonal variation of photosynthesis and photosynthetic efficiency in Phalaenopsis
- Creator:
- Pollet, B., Steppe, K., Dambre, P., van Labeke, M.-C., and Lemeur, R.
- Format:
- bez média and svazek
- Type:
- model:article and TEXT
- Subject:
- botanika, botany, chlorophyll fluorescence, CO2 assimilation, crassulacean acid metabolism, irradiance, photorespiration, temperature, and quantum yield
- Language:
- Multiple languages
- Description:
- Nowadays, a quest for efficient greenhouse heating strategies, and their related effects on the plant's performance, exists. In this study, the effects of a combination of warm days and cool nights in autumn and spring on the photosynthetic activity and efficiency of Phalaenopsis were evaluated; the latter, being poorly characterised in plants with crassulacean acid metabolism (CAM) and, to our knowledge, not reported before in Phalaenopsis. 24-h CO2 flux measurements and chlorophyll (Chl) fluorescence analyses were performed in both seasons on Phalaenopsis 'Hercules' exposed to relatively constant temperature regimes, 25.5/24.0°C (autumn) and 30/27°C (spring) respectively, and distinctive warm day/cool night temperature regimes, 27/20°C (autumn) and 36/24°C (spring), respectively. Cumulated leaf net CO2 uptake of the distinctive warm day/cool night temperature regimes declined with 10-16% as compared to the more constant temperature regimes, while the efficiency of carbon fixation revealed no substantial differences in both seasons. Nevertheless, a distinctive warm day/cool night temperature regime seemed to induce photorespiration. Although photorespiration is expected not to occur in CAM, the suppression of the leaf net CO2 exchange during Phase II and Phase IV as well as the slightly lower efficiency of carbon fixation for the distinctive warm day/cool night temperature regimes confirms the involvement of photorespiration in CAM. A seasonal effect was reflected in the leaf net CO2 exchange rate with considerably higher rates in spring. In addition, sufficiently high levels of photosynthetically active radiation (PAR) in spring led to an efficiency of carbon fixation of 1.06-1.27% which is about twice as high than in autumn. As a result, only in the case where a net energy reduction between the temperature regimes compensates for the reduction in net CO2 uptake, warm day/cool night temperature regimes may be recommended as a practical sustainable alternative. and B. Pollet ... [et al.].
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public