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822. Long-term acclimation of barley photosynthetic apparatus to narrow-band red and blue light
- Creator:
- Kochetova, G. V., Belyaeva, O. B., Gorshkova, D. S., Vlasova, T. A., Bassarskaya, E. M., Zhigalova, T. V., and Avercheva, O. V.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- LED, elektronová mikroskopie, spektrofluorimetrie, electron microscopy, spectrofluorimetry, spillover, 2, and 581
- Language:
- Multiple languages
- Description:
- Chloroplasts of barley plants grown under red light (RL, 660 nm) dramatically differed from the chloroplasts of plants raised under blue light (BL, 450 nm) or control plants (white light). The chloroplasts under RL had an extensive membrane system with high stacking degree and disordered irregular shaped stacks (shaggy-formed grana). After 5 h in darkness, dynamic rearrangements of chloroplast architecture in RL- and especially BL-grown plants were restricted compared with control plants. The light spectral quality affected the content and proportions of photosynthetic pigments. The leaves of RL-grown plants had the increased ratio of low-temperature fluorescence bands, F741/F683, corresponding to emission of PSI and PSII, respectively. This increase can be related to specific architecture of chloroplasts in RL-treated plants, providing close spacing between the two photosystems, which enhances energy transfer from PSII to PSI and facilitates the movement of LHCII toward PSI., G. V. Kochetova, O. B. Belyaeva, D. S. Gorshkova, T. A. Vlasova, E. M. Bassarskaya, T. V. Zhigalova, O. V. Avercheva., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
823. Loss of photosynthesis signals a metabolic reprogramming to sustain sugar homeostasis during senescence of green leaves: Role of cell wall hydrolases
- Creator:
- Biswal, B. and Pandey, J. K.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, cell wall hydrolases, senescence, sugar homeostasis, 2, and 581
- Language:
- Multiple languages
- Description:
- Leaf senescence is always associated with decline in photosynthesis, consequently a loss of cellular sugar. On the other hand, execution of senescence program needs energy and leaves, therefore, tend to collect sugars from other sources to sustain energy homeostasis. This sugar reprogramming induced by loss of sugar involves operation of a complex catabolic network. The exact molecular mechanism of induction and regulation of the network, however, is not fully resolved but the current literature available suggests sugar starvation as a signal for induction of several senescence-associated genes including the genes coding for the enzymes for degradation of cellular constituents and their conversion to respiratory sugars. The late expression of genes coding for the cell wall hydrolases and enhancement in the activity of these enzymes late during senescence are indicative of the cell wall polysaccharides as the last source of sugars to sustain energy homeostasis for execution of the senescence program., B. Biswal, J. K. Pandey., and Obsahuje bibliografické odkazy
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
824. Lotus corniculatus L. response to carbon dioxide concentration and radiation level variations
- Creator:
- Kostopoulou, P. and Karatassiou, M.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- světlo, light, elevace, index plasticity, ambient conditions, birdsfoot trefoil, elevation, photosynthetic rate, plasticity index, 2, and 581
- Language:
- Multiple languages
- Description:
- Carbon dioxide concentration and light conditions may greatly vary between mountainous and lowland areas determining the photosynthetic performance of plants species. This paper aimed to evaluate the photosynthetic responses of Lotus corniculatus, growing in a mountain and a lowland grassland, under low and high radiation and CO2 concentration. Net photosynthetic rate, stomatal conductance, transpiration rate, and intercellular CO2 concentration were measured while the water-use efficiency and the ratio of variable to maximal fluorescence were calculated. Photosynthetic response curves to different levels of radiation and intercellular CO2 partial pressure were estimated. Our results showed that high radiation and CO2 concentration enhanced water-use efficiency of plants at both sites, enabling them to use more efficiently the available water reserves under drought conditions. The increase of radiation and CO2 concentration would enhance the photosynthetic performance of the mountainous population of L. corniculatus, which overall seems to express higher phenotypic plasticity., P. Kostopoulou, M. Karatassiou., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
825. Louky Krkonošského národního parku pohledem rostlinných ekologů
- Creator:
- Skálová, Hana and František Krahulec
- Format:
- Type:
- article, články, model:article, and TEXT
- Subject:
- Životní prostředí a jeho ochrana, louky, národní parky, ekologie, Krkonošský národní park (Česko), Krkonoše (Česko a Polsko : pohoří), 2, and 502
- Language:
- Czech
- Description:
- Semi-natural grasslands form an important part of the National Park and determine the landscape character of the area. Due to migration and human activities, plant species from the foothills and alpine areas have come into contact in the montane zone and coexist in new communities. The mechanisms behind the high diversity of local grasslands have been investigated since the 1980s. and Hana Skálová, František Krahulec.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
826. Loupeživé výpravy a rozmnožování u otrokářských mravenců a další případy sociálního parazitismu
- Creator:
- Amcha, Pavel
- Format:
- bez média and svazek
- Type:
- article, text, články, journal articles, model:article, and TEXT
- Subject:
- Biologické vědy, biologie, mravencovití, rozmnožování (biologie), parazitičtí živočichové, otrokáři, loupeže, reproduction, biology, ants, parasitic animals, slaveholders, loupežení, parazitismus, parasitism, inkvilinie, duloze, otrokářští mravenci, loupeživí mravenci, 2, and 57/59
- Language:
- Czech
- Description:
- Článek popisuje tzv. závislý způsob zakládání kolonie u mravenců. Ten má několik stupňů závislosti - od závislosti na cizím mraveništi pouze v počátku vzniku kolonie (dočasná závislost) až po trvalé soužití dvou mravenčích druhů. To má několik stupňů, počínaje prostým hostováním (xenobióza) a konče příležitostným (fakultativním) otrokářstvím - tzv. inkvilinie, nebo trvalým (obligatorním) otrokářstvím - tzv. duloze. Trvalé otrokářství je spojeno s nutností pořádat otrokářské výpravy za plodem pomocných mravenců (otroků). Mimo jiné je jich využito i pro založení nové kolonie otrokářů., Dependent ways of nest foundation in some ant species are described. These include various types of social parasitism ranging from temporary parasitism to both optional and obligatory slavery. The latter is the strongest form of dependence of the slave-making ant on its slaves and is accompanied by the inability of the slaver species to survive without its slaves. On the other hand, slave-making ants are famous for their orientation in the field and movement over long distances. These abilities are used, e.g., by the European Amazon Ant (Polyergus rufescens) in its special strategy of nest foundation based on cooperation between workers and the freshly inseminated queen during a slavery raid., and Pavel Amcha.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
827. Lovci, nebo zahradníci?: komplexní výzkum vodních masožravých bublinatek
- Creator:
- Lubomír Adamec, Dagmara Sirová, Jaroslav Vrba, Jiří Bárta, Šantrůček, Jiří, and Karel Šimek
- Format:
- print, bez média, and svazek
- Type:
- article, text, články, journal articles, model:article, and TEXT
- Subject:
- Biologické vědy, masožravé rostliny, bublinatkovité, vodní rostliny, přírodovědný výzkum, fyziologie rostlin, carnivorous plants, Lentibulariaceae, water plants, natural science research, plant physiology, bublinatky, vodní bublinatky, Utricularia, 2, and 57/59
- Language:
- Czech
- Description:
- V návaznosti na naše předchozí články tento příspěvek shrnuje a osvětluje pozoruhodné až rekordní vlastnosti vodních masožravých rostlin bublinatek (Utricularia, Lentibulariaceae) na úrovni ekofyziologické, biofyzikální i molekulárně genetické. Patří mezi ně velice rychlý vrcholový růst prýtu, rekordně vysoká rychlost fotosyntézy a velmi účinná reutilizace N a P ze starých prýtů, ale nikoliv K. Byl prokázán velmi rychlý průběh spuštění pastí, jejich spontánní spouštění bez mechanického podnětu po určité době, rozsáhlé vylučování organických látek do tekutiny pastí k podpoře pasťových mikrobních komenensálů i komplexní regulace tvorby pastí., As a follow-up to our previous papers, this paper summarises and elucidates remarkable and record-breaking eco-physiological, biophysical, and molecular characteristics of aquatic carnivorous bladderworts (Utricularia, Lentibulariaceae). These include the very rapid apical shoot growth, record high photosynthetic rate, and very effective N and P (but not K) reutilization in old shoots. Moreover, an extremely rapid time-course of trap firing, their spontaneous firing without any mechanical stimulus after certain time periods, extensive secretion of organic substances to the trap fluid to support microbial trap commensals, and a complex regulation of trap production are shown and discussed here., and Lubomír Adamec, Dagmara Sirová, Jaroslav Vrba, Jiří Bárta, Jiří Šantrůček, Karel Šimek.
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
828. Low concentrations of glycine inhibit photorespiration and enhance the net rate of photosynthesis in Caragana korshinskii
- Creator:
- Kang, T., Wu, H. D., Lu, B. Y., Luo, X. J., Gong, C. M., and Bai, J.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, chlorofylová fluorescence, výměna plynu, pozitivní korelace, stomatální faktor, chlorophyll fluorescence, gas exchange, nonstomatal factor, stomatal factor, 2, and 581
- Language:
- Multiple languages
- Description:
- The inhibition of photorespiration can be used to improve plant carbon fixation. In order to compare the effects of three photorespiration inhibitors [glycine, NaHSO3, and isonicotinyl hydrazide (INH)], photosynthetic parameters of leaves sprayed respectively with these chemicals were examined and their inhibiting efficiency was evaluated in Caragana korshinskii. Our results showed that 5 mM glycine could reduce the photorespiratory rate (PR) effectively, while the net photosynthetic rate (PN), stomatal conductance (gs), and intercellular CO2 concentration (Ci) significantly increased. The ratio of electron flow for ribulose-1,5-bisphosphate (RuBP) carboxylation to RuBP oxygenation was elevated markedly. NaHSO3 and INH could also suppress the PR in some cases, whereas PN was not improved. The glyoxylate content increased considerably after application of low concentrations of glycine. These results suggested that low concentrations of glycine could suppress photorespiration by feed-back inhibition of glyoxylate and enhance photosynthesis by regulating gs, Ci, and the distribution of electron flow in C. korshinskii., T. Kang, H. D. Wu, B. Y. Lu, X. J. Luo, C. M. Gong, J. Bai., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
829. Low contribution of photosynthesis and water-use efficiency to improvement of grain yield in Chinese wheat
- Creator:
- Chen, X. and Hao, M.-D.
- Format:
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- Type:
- model:article and TEXT
- Subject:
- fotosyntéza, photosynthesis, agronomic traits, flag leaf, grain number per area unit, highland agricultural system, jointing stage, rate of photosynthesis per leaf area unit, stomatal conductance, thousand-grain mass, transpiration rate, water-use efficiency, winter wheat, 2, and 581
- Language:
- Multiple languages
- Description:
- The contribution of photosynthesis to yield improvement is important to know in order to determine future breeding strategies. The objectives of this study were to determine the contribution of photosynthesis and water-use efficiency (WUE) to grain yield improvement of facultative wheat (Triticum aestivum L.) cultivars on the Loess Plateau of China released between 1937 and 2004. The grain yield has increased nearly sevenfold during this period. Surprisingly, these increases were not correlated with the rate of photosynthesis per unit of leaf area when the cultivars were planted and managed in the same environment. The increases were also not correlated with transpiration rate, stomatal conductance, or WUE, except at the jointing stage. The total increase in photosynthesis may be due to enlargement of photosynthetic area and photosynthesis duration. The grain yield was positively correlated with the number of grains per unit of area (r = 0.855, P<0.05), harvest index (HI) (r = 0.885, P<0.01), and thousand-grain mass (r = 0.879, P<0.01). The increase in grain yield was limited by the grain number and the grain size (sink-limited) and the yield improvement was attributed to a rise in HI over the last 70 years in a highland agricultural system in China., X. Chen, M. -D. Hao., and Obsahuje seznam literatury
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public
830. Low doses of Pb affected Lactuca sativa photosynthetic performance
- Creator:
- Silva, S., Pinto, G., and Santos, C.
- Format:
- print, bez média, and svazek
- Type:
- model:article and TEXT
- Subject:
- fytotoxicita, olovo, phytotoxicity, lead, abiotický stres, fluorescence chlorofylu, výměna plynu, toxické kovy, fotosyntetický výkon, locika setá, abiotic stress, chlorophyll fluorescence, gas exchange, toxic metal, photosynthetic performance, 2, and 581
- Language:
- Multiple languages
- Description:
- The effects of soil and water contamination by lead (Pb) and the consequences on plant growth and yield are of great concern worldwide. Limits of the Pb concentration in water have been established by governmental institutions but these differ from each other. In this study, Lactuca sativa (var. Reine de Mai) plants were exposed to low Pb(NO3)2 doses (0.05-20 mg L-1), including the recommended limit values for irrigation water by the Food and Agriculture Organization (FAO). After 28 d of exposure, lettuce plants did not present visible morphological alterations or growth impairment, but CO2 assimilation rate (PN), photochemical quenching, and effective quantum efficiency of PSII were negatively affected, while intercellular CO2 concentration, stomatal conductance, or transpiration rate were not influenced. Our results suggested that limitations on photosynthesis occurred from different reasons than due to the decrease of internal CO2 availability, alterations of photophosphorylation, and/or electron transport rate. Thus, this lettuce cultivar showed photosynthetic susceptibility to low doses of Pb, even at lower concentrations than those maximal allowed for irrigation water by FAO. Furthermore, PN seemed to be the most sensitive biomarker for evaluation of Pb susceptibility., S. Silva, G. Pinto, C. Santos., and Obsahuje bibliografii
- Rights:
- http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public