Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Photocontrol of Development in Algae (1988)
    Palo Alto, Calif. : Annual Reviews
    Annual Review of Plant Physiology and Plant Molecular Biology 39 (1988), S. 157-174 
    Details
    ISSN: 1040-2519
    Source: Annual Reviews Electronic Back Volume Collection 1932-2001ff
    Topics: Biology
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1146/annurev.pp.39.060188.001105
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Contribution of the UV component of natural sunlight to photoinhibition of photosynthesis in six species of subtidal brown and red seaweeds (2001)
    Oxford, UK : Blackwell Science, Ltd
    Plant, cell & environment 24 (2001), S. 0 
    Details
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Field-collected specimens of three species of Laminaria and three species of subtidal red algae (Delesseria sanguinea, Plocamium cartilagineum and Phyllophora pseudoceranoides) were exposed to natural summer sunlight on Helgoland (southern North Sea) for up to 4 h at 15 °C. Dark-adapted variable fluorescence (Fv : Fm) was measured immediately after these treatments, and following 6, 24 and 48 h of recovery in moderate irradiances of white light. The response of plants to the full spectrum of natural sunlight was compared with that to PAR alone, UV-A + visible, UV-A + UV-B, or UV-A alone. The Fv : Fm values of all species were reduced to minimal values after 4 h in all of these treatments, but those of the more resistant species (Laminaria spp. and P. pseudoceranoides) were higher after shorter exposures to UV radiation alone than to PAR with or without UV. The recovery of Fv : Fm in all species was also more rapid in the two treatments that contained UV radiation alone than in those that included PAR. These results suggest that it is the high irradiances of PAR in natural sunlight which are responsible for the photoinhibition of photosynthesis of subtidal seaweeds and that the current ambient irradiances of UV radiation (either UV-B or UV-A) in northern temperate latitudes would not contribute significantly to this photoinhibition.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1046/j.1365-3040.2001.00765.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Influence of carbon supply on the stimulation of light-saturated photosynthesis by blue light in Laminaria saccharina: implications for the mechanism of carbon acquisition in higher brown algae (1996)
    Oxford, UK : Blackwell Publishing Ltd
    Plant, cell & environment 19 (1996), S. 0 
    Details
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: In saturating irradiances of red light, photosynthesis of Laminaria saccharina (L.) Lamouroux was stimulated by low irradiances of continuous blue light only when the supply of dissolved inorganic carbon (DIC) was limiting. The degree of this stimulation was inversely proportional to the logarithm of the concentration of free CO2, whether this was adjusted by varying the total DIC or the pH at a given DIC concentration. The final pH reached in a closed system was higher in blue light than in red light. Both acetazolamide and ethoxyzolamide suppressed the responses to blue light almost completely, but reduced photosynthesis in red light by only 30%. Buffering the pH of the seawater also suppressed the stimulation of photosynthesis by blue light without affecting the photosynthetic rate in red light. The transient stimulation of O2 evolution by a blue light pulse was not accompanied by a corresponding increase in CO2 consumption. These observations could be explained if, in analogy to the mechanism proposed for Ectocarpus (Schmid, Mills & Dring 1996, Plant Cell and Environment 19,373–382, this issue, accompanying paper), photosynthesis was supported by a blue-light-activated release of CO2 from an internal store. We suggest that the store is located in the vacuoles of the cortical tissue of the blades. The main photosynthetic tissue, however, is in the overlying meristoderm, and blue-light-activated mobilization of the store could stimulate O2 evolution only if periplasmic carbonic anhydrase was available to facilitate CO2 uptake from the cortex.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3040.1996.tb00330.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Influence of carbon supply on the circadian rhythmicity of photosynthesis and its stimulation by blue light in Ectocarpus siliculosus: clues to the mechanism of inorganic carbon acquisition in lower brown algae (1996)
    Oxford, UK : Blackwell Publishing Ltd
    Plant, cell & environment 19 (1996), S. 0 
    Details
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Stimulation or light-saturated rates of photosynthesis in Ectocarpus siliculosus (Dillwyn) Lyngb. by blue light was eliminated by increasing dissolved inorganic carbon (DIC) or by lowering pH in natural seawater. The amplitude of the circadian rhythm of photosynthesis was also diminished under these conditions, and the pH compensation points in a closed system were higher in the presence of blue light and during the circadian day. These observations suggest that blue light and the circadian clock regulate the activity of a carbon acquisition system in these plants. The inhibitor of external carbonic anhydrase, acetazolamide, reduced overall rates of photosynthesis by only about 30%, but ethoxyzolamide suppressed the circadian rhythm of photosynthesis almost completely and markedly reduced the duration of responses to blue light pulses. Similar patterns were obtained when photosynthesis was measured in strongly limiting DIC concentrations (0–0.5 mol m−3). Since blue light stimulated photosynthesis under these conditions of strong carbon limitation, we suggest that blue light activates the release of CO2 from an internal CO2 store. We propose a metabolic pathway with similarities to that of CAM plants. Non-photosynthetic fixation leads to the accumulation of a storage metabolite. The circadian clock and blue light control the mobilization of CO2 at the site of decarboxylation of this metabolite. In the presence of continuous blue light the pathway is proposed to cycle and act as a pump for CO2 into the chloroplasts. This hypothesis helps to explain a number of previously reported peculiarities of brown algal photosynthesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3040.1996.tb00329.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Interactions of blue light and inorganic carbon supply in the control of light-saturated photosynthesis in brown algae (1992)
    Oxford, UK : Blackwell Publishing Ltd
    Plant, cell & environment 15 (1992), S. 0 
    Details
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Photosynthetic capacities of five species of brown algae in red light were found to be strongly limited by the inorganic carbon supply of natural sea water. Under these conditions, pH 8·2 and dissolved inorganic carbon concentration (DIG) of 2·1 mol m−3, a short pulse of blue light was found to increase the subsequent rate of photosynthesis in saturating red light. The degree of blue light stimulation varied between species, ranging from an increase of over 200% of the original rate in Colpomenia peregrins to only 10% in Dictyota dichotoma. Increasing the DIG concentration of sea water by bicarbonate addition resulted in carbon saturation of photosynthesis in all five species. Blue light stimulation was greatly reduced at these higher DIG concentrations. The response in Laminaria digitata was examined in more detail by manipulation of pH and DIG to produce solutions with different concentrations of dissolved CO2. At a CO2 concentration typical of normal sea water (12·4 mmol m−3), blue light treatment increased photosynthetic rate by approximately 50%. Blue light stimulation was increased to over 150% at CO2 concentrations below that of sea water, whereas at concentrations above that of sea water, the effect was diminished. Therefore, the effect of blue light on photosynthetic capacity appears to involve an increase in the rate of supply of carbon dioxide to the plant.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/j.1365-3040.1992.tb01478.x
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Underwater illumination (1984)
    [s.l.] : Nature Publishing Group
    Nature 309 (1984), S. 382-382 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] THERE are advantages and disadvantages in attempting to bridge the gap between two scientific subjects. Ideally, the bridge will provide a route for the two-way traffic of ideas and scientists; but if the two subjects are in very different states of development, it may result instead in a ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/309382a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Phytochrome in Red Alga, Porphyra tenera (1967)
    [s.l.] : Nature Publishing Group
    Nature 215 (1967), S. 1411-1412 
    Details
    ISSN: 1476-4687
    Source: Nature Archives 1869 - 2009
    Topics: Biology , Chemistry and Pharmacology , Medicine , Natural Sciences in General , Physics
    Notes: [Auszug] Culture methods for the conchocelis, and the techniques used for estimating growth and reproduction, have already been described2. The apparatus used for the irradiation of cultures with monochromatic light was similar to that described by Wilson and Schwabe3 for similar work with Lunularia. A set ...
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1038/2151411a0
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    A photoperiodic response mediated by blue light in the brown alga Scytosiphon lomentaria (1975)
    Springer
    Planta 125 (1975), S. 25-32 
    Details
    ISSN: 1432-2048
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The crustose phase of Scytosiphon lomentaria (Lyngb.) J. Ag. persists indefinitely in 16 h of white light per day, but produces erect, cylindrical thalli vegetatively in 8-h days. The critical daylength for this short-day (SD) response is sharply defined, and, between 12 and 13 h, differences in daylength of only 15 min produce substantial differences in response. A significant response to SD can be induced by as few as 4 SD cycles, but 10–12 cycles are required to saturate the response and induce more than 90% of the plants to form thalli. The response to SD is completely inhibited by a 1-min light-break with a low irradiance of blue light, given in the middle of a 16-h dark period, but is unaffected by longer periods and higher irradiances of red or far-red light. There is good reciprocity between the irradiance and the length of a light-break with blue light, and 50% inhibition of the response to SD is induced by about 2 nE cm-2 at 449 nm. All attempts to reverse the inhibitory effects of blue light by subsequent irradiation with another wavelength have so far failed. These results indicate that phytochrome is not the photoreceptor pigment for this response, in spite of the similarity of the response in all other respects to the photoperiodic responses of flowering plants and other algae.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00388870
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Phosphate uptake by intertidal algae in relation to zonation and season (1990)
    Springer
    Marine biology 107 (1990), S. 281-289 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The removal of phosphate from ambient seawater by whole plants of five species of fucoid algae, collected from the east coast of N. Ireland in 1988 and 1989, was followed over 6-h periods. A transient uptake pattern was observed forPelvetia canaliculata (L.) Dcne. et Thuret,Fucus spiralis L.,F. vesiculosus L. andF. serratus L., consisting of an initial period of high uptake, followed by a phase of zero uptake and then a period at an intermediate rate.Ascophyllum nodosum (L.) Le Jolis had a constant slow rate of uptake over 6 h. The initial uptake rate ofF. spiralis was significantly greater than that of any other species. Phosphate uptake over a 2-h period was measured at concentrations ranging from that of ambient seawater to 25µg-at. l−1 for whole plants ofF. spiralis andF. serratus, using a large scale batch method. A small scale batch method was used for whole plants ofP. canaliculata and sections of the other four species investigated. Uptake abilities of the algae at low concentrations of phosphate were compared using the parameterV 1 (the uptake rate at 1µg-at. l−1) and at high concentrations usingV max, the maximum uptake rate. These kinetic parameters of uptake were calculated using a method that avoids bias and permits statistical evaluation of the results. The fucoid algae studied could be divided into two distinct groups on the basis of their abilities to take up phosphate from seawater.P. canaliculata andA. nodosum had low values ofV 1 in winter, which were also correlated with their positions on the shore and did not vary between winter and summer. TheFucus species had higher values ofV 1 in winter, which were also correlated with their positions on the shore. In summer, however,V 1-values for these species decreased and no longer correlated with their shore heights. TheV max-value forF. spiralis was higher in winter than in summer but was signifcantly greater than that of any other species at all times of year. The ecological significance ofV max is discussed in relation to nutrient limitation and the possible occurrence of patches of high nutrient concentration in the intertidal environment.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01319827
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Influence of ultraviolet-radiation on chlorophyll fluorescence and growth in different life-history stages of three species of Laminaria (phaeophyta) (1996)
    Springer
    Marine biology 126 (1996), S. 183-191 
    Details
    ISSN: 1432-1793
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Zoospores, gametophytes, young sporophytes and discs cut from mature sporophytes of Laminaria digitata, L. hyperborea and L. saccharina were exposed in the laboratory to UV-radiation, with a spectral composition and irradiance similar to natural sunlight, for periods ranging from 15 min to 8 d, and were then returned to white light. Germination of zoospores and the growth of gametophytes were reduced after exposures to UV longer than 1 h, whereas UV had little effect on the growth of young or mature sporophytes unless exposure continued for more than 48 h. The variable fluorescence (F v:Fm) of all stages was strongly reduced immediately after short exposures to UV, but recovered almost completely within 24 h. However, exposure of gametophytes to UV for 〉4 h resulted in little or no recovery of F v:Fm, whereas 〉16 h of UV were required to produce this result in young sporophytes, and 〉48 h in mature sporophytes. Thus, sensitivity to UV-radiation decreased from gametophytes to sporophytes, and with increasing age of sporophytes, but, in gametophytes, growth appeared to be a more sensitive indicator of UV-damage than F v:Fm after 24 h recovery. The responses to UV of the zoospores and gametophytes of all three species were similar, but both growth and fluorescence measurements suggested that the sporophytes of L. saccharina were more sensitive to UV than those of the other two species.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00347443
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...