Staff Publications

Staff Publications

  • external user (warningwarning)
  • Log in as
  • language uk
  • About

    'Staff publications' is the digital repository of Wageningen University & Research

    'Staff publications' contains references to publications authored by Wageningen University staff from 1976 onward.

    Publications authored by the staff of the Research Institutes are available from 1995 onwards.

    Full text documents are added when available. The database is updated daily and currently holds about 240,000 items, of which 72,000 in open access.

    We have a manual that explains all the features 

Record number 415032
Title The analysis of PS II photochemical activity using single and multi- turnover excitations
Author(s) Vredenberg, W.J.; Durchan, M.; Prášil, O.
Source Journal of Photochemistry and Photobiology. B, Biology 107 (2012). - ISSN 1011-1344 - p. 45 - 54.
Department(s) Laboratory of Plant Physiology
Publication type Refereed Article in a scientific journal
Publication year 2012
Keyword(s) chlorophyll-a fluorescence - photosystem-ii - in-vivo - photoelectrochemical control - induction kinetics - electron-transfer - higher-plants - redox state - flash - yield
Abstract Paper describes chlorophyll a fluorescence measurements in algal cells, and intact plant leaves and isolated chloroplasts. It focuses on amplitude and 10 µs-resolved kinetics of variable fluorescence responses upon excitation with fluorescence-saturating pulses (SP) and with 25 µs saturating single turnover flashes (STF) which are exposed before, during and after a 100 s actinic illumination (AL) of low and high intensity. In addition to the amply documented suppression of the maximal variable fluorescence from Fm to F’m, the relative proportion of the distinguished O-J- , J-I and I-P-phases of an SP-induced response is shown to be distinctly different in dark- and light-adapted leaves. The O-J-phase in the 0.01 to 1 ms time range is much less sensitive to light adaptation than the other phases in the 1 – 200 ms range. In algae and chloroplasts, the amplitude FmSTF of the STF-induced response is hardly affected by a shift from the dark- to the light-activated steady state. The results support the hypothesis that the maximal variable fluorescence Fm induced by a multiple-turnover, fluorescence-saturating pulse (SP), is associated with the release of photochemical and photoelectrochemical quenching. It is argued that the OJIPMT- or Kautsky induction curve of variable chlorophyll fluorescence in the 0 – 100 s time range is the reflection of the release of photochemical quenching supplemented with a temporary Photosystem I (PSI)-dependent photoelectric stimulation and transient release of photoelectrochemical quenching of radiative energy loss in the Photosystem II (PSII) antennas, rather than solely of a decrease in PSII photochemical activity as is usually concluded.
There are no comments yet. You can post the first one!
Post a comment
Please log in to use this service. Login as Wageningen University & Research user or guest user in upper right hand corner of this page.