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Start Over Format svazek Subject photosynthesis

391. Plastid-nuclear complexes in the photosynthesizing cells from their mitosis up to programmed death

Creator:
Selga, T., Selga, M., and Ozoliņa, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, photosynthesis, chloroplasts, Nicotiana tabaccum, nuclei, programmed cell death, 2, and 581
Language:
Multiple languages
Description:
Permanent plastid-nuclear complexes (PNCs) exist in tobacco cells from their mitosis up to programmed cell death (PCD). PNCs in senescing cells of tobacco leaves were typical by enclosure of peroxisomes and mitochondria among chloroplasts which were in contact with nucleus. Such a complex position provides simultaneous interaction of these organelles and direct regulation of metabolism and PCD avoiding the cytosol. and T. Selga, M. Selga, A. Ozoliņa.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

393. Positive correlation between potassium uptake and salt tolerance in wheat

Creator:
Cheng, D., Wu, G., and Zheng, Y.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, photosynthesis, gas exchange, malondialdehyde, peroxidase, reactive oxygen species, Triticum aestivum L., 2, and 581
Language:
Multiple languages
Description:
The aim of our study was to answer whether any positive correlation exists between K+ uptake and salt tolerance in wheat. We carried out a sand-culture experiment with salt-tolerant, DK961 (ST), and salt-sensitive, JN17 (SS), wheat cultivars, where photosynthesis, the K+/Na+ ratio, growth, and the biomass yield were examined. The seeds were exposed for four weeks to six NaCl concentrations (50, 100, 150, 200, 250, and 300 mM), which were embodied in the Hoagland solution. Salinity-induced decrease of K+ or increase in the Na+ content was much smaller in ST than that in SS. The reductions in the light-saturated photosynthetic rate (P Nmax) and chlorophyll content caused by salinity were smaller in the ST compared to SS. Stomatal conductance decreased in both cultivars under saline conditions; nevertheless, it was lower in SS than in ST. The antioxidative capacity was higher in ST than that in SS under saline conditions. Significant positive correlations were observed in both cultivars between K+ contents and P Nmax/biomass yields. We suggest that higher-affinity K+ uptake might play a key role in higher salt tolerance and it might be a reliable indicator for breeding new species of salt-tolerant wheat., D. Cheng, G. Wu, Y. Zheng., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

395. Primární procesy ve fotosyntéze: od buňky ke kvantové superpozici a zpět

Creator:
Mančal, Tomáš
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, buňky, fotony, photosynthesis, cells, photons, 6, and 53
Language:
Czech and English
Description:
Výzkum primárních procesů fotosyntézy probíhá na trojmezí tří velkých přírodních věd: fyziky, chemie a biologie. Předmětem tohoto článku je stručný přehled sledu elementráních chemických a fyzikálních pochodů od záchytu fotonu po syntézu adenosintrifosfátu (ATP) a úvod do kvantové teorie světlosběrných fotosyntetických antén., Research of primary processes of photosynthesis occurs at the boundary of three great natural sciences: physics, chemistry and biology. This article gives a brief overview of the elementary chemical and physical processes from the absorption of a photon to the synthesis of adenosintriphosphate molecules, and it introduces the reader to the theory of photosynthetic light-harvesting antennae., Tomáš Mančal., and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

396. Prof. RNDr. Danuše Sofrová, CSc.: obituary

Creator:
Synková, Helena, Masojídek, Jiří, Komenda, Josef, Wilhelm, Jiří, Wilhelmová, Naďa, and Vácha, František
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
Sofrová, Danuše, 1938-2016, biochemici, fotosyntéza, biochemists, photosynthesis, 2, and 581
Language:
Multiple languages
Description:
Helena Synková, Jiří Masojídek, Josef Komenda, Jiří Wilhelm, Naďa Wilhelmová, František Vácha. and Obsahuje bibliografii
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

397. Promotion of 5-aminolevulinic acid treatment on leaf photosynthesis is related with increase of antioxidant enzyme activity in watermelon seedlings grown under shade condition

Creator:
Sun, Y.-P., Zhang, Z.-P., and Wang, L.-J.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
5-aminolevulinic acid, antioxidant enzymes, chlorophyll fluorescence, JIP test, low light stress, photosynthesis, and watermelon
Language:
Multiple languages
Description:
Watermelon [Citrullus lanatus (Thunb.) Mansfeld] is a photophilic plant, whose net photosynthetic rate was significantly decreased when seedlings were grown under low light condition. However, treatment with 100 mg kg-1 5-aminolevulinic acid (ALA) could significantly restore the photosynthetic ability under the environmental stress. The parameters of leaf gas exchange, chlorophyll modulated fluorescence and fast induction fluorescence of the ALA-treated plants were higher than that of the control. Additionally, ALA treatment increased the activities of antioxidant enzymes, including superoxide dismutase (SOD), peroxidase (POD) and ascorbate peroxidase (APX). Nevertheless, the treatment of diethyldithiocarbamate (DDC), an inhibitor of SOD activity, dramatically depressed photosynthesis of watermelon leaves, while ALA could reverse the inhibition of DDC. Therefore, it can be deduced that ALA promotion on photosynthesis of watermelon leaves under low light stress is attributed to its promotion on antioxidant enzyme activities, and the increased activities of the enzymes, which are mainly located near the reaction centers of PSI, can scavenge superoxide anions, leading to an increase of apparent electron transport rate and an alleviation of photosynthetic photoinhibition under the stressed environment. and Y.-P. Sun, Z.-P. Zhang, L.-J. Wang.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

398. Prospects of photosynthetic research for increasing agricultural productivity, with emphasis on the tropical C4 Amaranthus and the cassava C3-C4 crops

Creator:
El-Sharkawy, M. A.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
photosynthesis, agricultural sustainability, breeding, C3, C4, C3-C4 species, canopy, climate change, crop modeling, environmental stress, enzyme, food security, genetic engineering, grain, leaf Kranz anatomy, photorespiration, photosynthetic pathway, protein, starch, storage-root, water, yield, 2, and 581
Language:
Multiple languages
Description:
Productivity of most improved major food crops showed stagnation in the past decades. As human population is projected to reach 9-10 billion by the end of the 21st century, agricultural productivity must be increased to ensure their demands. Photosynthetic capacity is the basic process underlying primary biological productivity in green plants and enhancing it might lead to increasing potential of the crop yields. Several approaches may improve the photosynthetic capacity, including integrated systems management, in order to close wide gaps between actual farmer’s and the optimum obtainable yield. Conventional and molecular genetic improvement to increase leaf net photosynthesis (P N) are viable approaches, which have been recently shown in few crops. Bioengineering the more efficient CC4 into C3 system is another ambitious approach that is currently being applied to the C3 rice crop. Two under-researched, yet old important crops native to the tropic Americas (i.e., the CC4 amaranths and the C3-CC4 intermediate cassava), have shown high potential P N, high productivity, high water use efficiency, and tolerance to heat and drought stresses. These physiological traits make them suitable for future agricultural systems, particularly in a globally warming climate. Work on crop canopy photosynthesis included that on flowering genes, which control formation and decline of the canopy photosynthetic activity, have contributed to the climate change research effort. The plant breeders need to select for higher P N to enhance the yield and crop tolerance to environmental stresses. The plant science instructors, and researchers, for various reasons, need to focus more on tropical species and to use the research, highlighted here, as an example of how to increase their yields., M. A. El-Sharkawy., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

399. Protection of winter rape photosystem 2 by 24-epibrassinolide under cadmium stress

Creator:
Janeczko, A., Kościelniak, J., Pilipowicz, M., Szarek-Łukaszewska, G., and Skoczowski, A.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
carotenoids, chlorophyll fluorescence induction, photosynthesis, and winter rape
Language:
Multiple languages
Description:
Seedlings of winter rape were cultured in vitro on media containing 24-epibrassinolide, EBR (100 nM) and cadmium (300 µM). After 14 d of growth, fast fluorescence kinetics of chlorophyll (Chl) a and contents of photosynthetic pigments and Cd in cotyledons were measured. Cd was strongly accumulated but its content in cotyledons was 14.7 % smaller in the presence of EBR. Neither Cd nor EBR influenced the contents of Chl a and b and carotenoids. Cd lowered the specific energy fluxes per excited cross section (CS) of cotyledon. The number of active reaction centres (RC) of photosystem 2 (RC/CS) decreased by about 21.0 % and the transport of photosynthetic electrons (ET0/CS) by about 17.1 %. Simultaneously, under the influence of Cd, the activity of O2 evolving centres (OEC) diminished by about 19.5 % and energy dissipation (DI0/CS) increased by about 14.6 %. In the cotyledons of seedlings grown on media without Cd, EBR induced only a small increase in the activity of most photochemical reactions per CS. However, EBR strongly affected seedlings cultured with cadmium. Specific energy fluxes TR0/CS and ET0/CS of the cotyledons of plants Cd+EBR media were about 10.9 and 20.9 % higher, respectively, than values obtained for plants grown with Cd only. EBR also limited the increase of DI0/CS induced by Cd and simultaneously protected the complex of OEC against a decrease of activity. Hence EBR reduces the toxic effect of Cd on photochemical processes by diminishing the damage of photochemical RCs and OECs as well as maintaining efficient photosynthetic electron transport. and A. Janeczko ... [et al.].
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

400. Proteomic study reveals photosynthesis as downstream of both MAP kinase and cAMP signaling pathways in Chlamydomonas reinhardtii

Creator:
Lee, C., Rhee, J.-K., Kim, D. G., and Choi, Y.-E.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
fotosyntéza, photosynthesis, gene regulation, mass spectrometry, two-dimensional gel electrophoresis, 2, and 581
Language:
Multiple languages
Description:
Previously, our data indicated that both cAMP and MAP kinase signaling play important roles in microalgal physiology as well as in lipid or carotenoid biosynthesis. In order to understand downstream genes of these signaling pathways, we employed proteomics approach. Both signal pathways were first altered with specific signaling inhibitors or modulators. Treatment of specific inhibitors changed microalgal size and increased lipid contents. With the microalgal cells after treatments of specific signaling inhibitor or modulators, we performed the proteomics analysis to identify downstream genes responsible for these phenotypes. Interestingly, multiple photosynthesis genes were identified, particularly proteins associated with PSII. Our data suggested that MAP kinase and cAMP signaling affect the photosynthesis, thereby leading to microalgal lipid or carotenoid biosynthesis., C. Lee, J.-K. Rhee, D. G. Kim, Y.-E. Choi., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public