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
    An analysis of photosynthetic response and adaptation to temperature in higher plants: temperature acclimation in the desert evergreen Nerium oleander L (1982)
    Oxford, UK : Blackwell Publishing Ltd
    Plant, cell & environment 5 (1982), S. 0 
    Details
    ISSN: 1365-3040
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Biology
    Notes: Abstract. Factors underlying the process of photosynthetic acclimation to temperature were investigated for the shrub Nerium oleander L. Ramets of a single clone were grown under day/night temperature regimes of 20°C/15°C or 45°C/32°C. Plants grown at the lower temperature regime possessed rates of photosynthesis twice that of the high-temperature grown plants when CO2 fixation was measured at 20°C. In contrast, the plants grown at the high-temperature regime had twice the rate of CO2 fixation of the 20°C/l 5°C-grown plants at a measurement temperature of 45° C. It was determined that the ability to acclimate to changes in temperature regime was present in fully mature leaves. A reciprocal transfer of plants between the two growth regimes resulted in the appearance of the CO2 fixation characteristics appropriate to the new growth temperature after 12–14d. The response of CO2 fixation to light, temperature, and CO2 partial pressure and the temperature responses of soluble and membrane-bound photosynthetic enzyme systems were analysed to determine which components might be responsible for the superior photosynthetic performance of the 20°C/I5°C-grown plants at 20°C, and the enhanced high-temperature stability of the 45°C/32°C plants. The measured photosynthetic capacity of the 20°C/15°C plants could not be attributed to gross morphological, stomatal, or other physical changes, or to a general increase in the concentration of components of the photosynthetic process. Only a single enzyme, Fru-P2 phosphatase, was affected to an extent similar to that of photosynthesis. The enhanced thermal stability of the 45°C/32°C plants may be attributed primarily to an enhanced stability of the chloroplast membrane-bound enzymatic activities and the stability of the photosynthetic carbon metabolism enzymes which require lighl for activation.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1111/1365-3040.ep11587620
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    Photosynthetic characteristics of plants of a Californian cool coastal environment (1983)
    Springer
    Oecologia 57 (1983), S. 38-42 
    Details
    ISSN: 1432-1939
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Herbaceous perennials native to coastal bluffs in northern California all had similar photosynthetic characteristics: moderate photosynthetic capacities, light saturation at relatively low irradiances, and low photosynthetic temperature optima. They all decreased stomatal conductance in response to decreased humidity. Though the coastal habitat generally has high humidities and cool air temperatures leaf microclimatic conditions lead frequently to large vapor-concentration gradients between leaf and air. Stomatal sensitivty to the vapor-concentration gradient may result in important plant-water conservation in this summer drought habitat.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00379559
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Seasonal changes in net photosynthesis of Atriplex hymenelytra shrubs growing in Death Valley, California (1974)
    Springer
    Oecologia 17 (1974), S. 111-121 
    Details
    ISSN: 1432-1939
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Field measurements of CO2 and water vapor exchange were made on Atriplex hymenelytra (Torr.) Wats. shrubs growing in Death Valley, California during March 1971 and July 1972. Rates of CO2 uptake and leaf conductances were substantially higher in March as compared to July. In spite of the large differences in ambient temperatures in March and July, no adaptive acclimation response was apparent in the temperature dependence of photosynthesis. Photosynthesis transpiration ratios at typical midday leaf temperatures were much higher in March than in July. High water use efficiency results from a combination of the C4 photosynthetic pathway, relatively low leaf conductances, and maximum growth and photosynthetic activity during the cooler months of the year.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00346274
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    The energy balance of leaves of the evergreen desert shrub Atriplex hymenelytra (1977)
    Springer
    Oecologia 29 (1977), S. 301-310 
    Details
    ISSN: 1432-1939
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Atriplex hymenelytra is an evergreen shrub distributed in the hot deserts of parts of Mexico and the southwestern United States. The leaves of the species have a number of characteristics that are adaptive in a hot, dry environment, some of which change seasonally. Steeply angled leaves reduce midday solar interception, yet result in relatively high interception when solar angles are low and vapor pressure deficits are at a minimum. The leaves substantially reduce their absorptance of incident radiation during the hot periods of the year by changing their moisture and hence dissolved salt contents. At these times the light intensity required for saturation of photosynthesis is low and a reduction in the radiation absorbed by the leaves therefore results in a greater water-use efficiency.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00345804
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Photoinhibition of photosynthesis in intact bean leaves: role of light and temperature, and requirement for chloroplast-protein synthesis during recovery (1986)
    Springer
    Planta 168 (1986), S. 253-260 
    Details
    ISSN: 1432-2048
    Keywords: Chlorophyll fluorescence ; Light and photoinhibition ; Phaseolus (photoinhibition) ; Photoinhibition of photosynthesis (recovery) ; Temperature and photoinhibition
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Photoinhibition of photosynthesis was induced in intact leaves of Phaseolus vulgaris L. grown at a photon flux density (PFD; photon fluence rate) of 300 μmol·m-2·s-1, by exposure to a PFD of 1400 μmol·m-2·s-1. Subsequent recovery from photoinhibition was followed at temperatures ranging from 5 to 35°C and at a PFD of either 20 or 140 μmol·m-2·s-1 or in complete darkness. Photoinhibition and recovery were monitored mainly by chlorophyll fluorescence emission at 77K but also by photosynthetic O2 evolution. The effects of the protein-synthesis inhibitors, cycloheximide and chloramphenicol, on photoinhibition and recovery were also determined. The results demonstrate that recovery was temperature-dependent with rates slow below 15°C and optimal at 30°C. Light was required for maximum recovery but the process was light-saturated at a PFD of 20 μmol·m-2·s-1. Chloramphenicol, but not cycloheximide, inactivated the repair process, indicating that recovery involved the synthesis of one or more chloroplast-encoded proteins. With chloramphenicol, it was shown that photoinhibition and recovery occurred concomitantly. The temperature-dependency of the photoinhibition process was, therefore, in part determined by the effect of temperature on the recovery process. Consequently, photoinhibition is the net difference between the rate of damage and the rate of repair. The susceptibility of chilling-sensitive plant species to photoinhibition at low temperatures is proposed to result from the low rates of recovery in this temperature range.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00402971
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Remote sensing of the xanthophyll cycle and chlorophyll fluorescence in sunflower leaves and canopies (1990)
    Springer
    Oecologia 85 (1990), S. 1-7 
    Details
    ISSN: 1432-1939
    Keywords: Chlorophyll fluorescence ; Photosynthesis ; Remote sensing ; Sunflower (Helianthus annuus) ; Xanthophyll cycle
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary Sudden illumination of sunflower (Helianthus annuus L. cv. CGL 208) leaves and canopies led to excess absorbed PFD and induced apparent reflectance changes in the green, red and near-infrared detectable with a remote spectroradiometer. The green shift, centered near 531 nm, was caused by reflectance changes associated with the de-epoxidation of violaxanthin to zeaxanthin via antheraxanthin and with the chloroplast thylakoid pH gradient. The red (685 nm) and near-infrared (738 nm) signals were due to quenching of chlorophyll fluorescence. Remote sensing of shifts in these spectral regions provides non-destructive information on in situ photosynthetic performance and could lead to improved techniques for remote sensing of canopy photosynthesis.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00317336
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Pubescence and leaf spectral characteristics in a desert shrub, Encelia farinosa (1978)
    Springer
    Oecologia 36 (1978), S. 151-162 
    Details
    ISSN: 1432-1939
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Summary The effects of leaf hairs (pubescence) on leaf spectral characteristics were measured for the drought-deciduous desert shrub Encelia farinosa. Leaf absorptance to solar radiation is diminished by the presence of pubescence. The pubescence appears to be reflective only after the hairs have dried out. There are seasonal changes in leaf absorptance; leaves produced at the beginning of a growing season have high absorptances, whereas leaves produced during the growing season are more pubescent and have lower absorptances. The decrease in leaf absorptance is the result of an increase in pubescence density and thickness. Between 400 and 700 nm (visible wavelengths), pubescence serves as a blanket reflector. However, over the entire solar spectrum (400–3000 nm), the pubescence preferentially reflects near infrared radiation (700–3000 nm) over photosynthetically useful solar radiation (400–700 nm). Leaf absorptance to solar radiation (400–3000 nm) varies between 46 and 16%, depending on pubescence; whereas leaf absorptance to photosynthetically useful radiation (400–700 nm) may vary from 81 to 29%.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00349805
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Evaluation of a mobile unit for indirect calorimetry during spontaneous ventilation (1986)
    Springer
    Journal of clinical monitoring and computing 3 (1986), S. 251-257 
    Details
    ISSN: 1573-2614
    Keywords: Oxygen uptake ; oxygen consumption ; energy expenditure ; indirect calorimetry ; ventilated hood system ; canopy system ; patients ; evaluation
    Source: Springer Online Journal Archives 1860-2000
    Topics: Computer Science , Medicine
    Notes: Summary The Mijnhardt Oxycon-4 (OX-4), designed for measurements of gas exchange during exercise using a mouth-piece, was adapted for use in recumbant patients by the introduction of a transparent canopy and a suction device. This system was evaluated in laboratory models and in patients.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01724393
    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...