New Fluorescence Parameters for the Determination of QA Redox State and Excitation Energy Fluxes

  title={New Fluorescence Parameters for the Determination of QA Redox State and Excitation Energy Fluxes},
  author={David M. Kramer and Giles N. Johnson and Olavi Kiirats and Gerald E. Edwards},
  journal={Photosynthesis Research},
A number of useful photosynthetic parameters are commonly derived from saturation pulse-induced fluorescence analysis. We show, that qP, an estimate of the fraction of open centers, is based on a pure ‘puddle’ antenna model, where each Photosystem (PS) II center possesses its own independent antenna system. This parameter is incompatible with more realistic models of the photosynthetic unit, where reaction centers are connected by shared antenna, that is, the so-called ‘lake’ or ‘connected… 

Chlorophyll a fluorescence: beyond the limits of the QA model

This review focuses on the processes determining the fluorescence rise on a dark-to-light transition and critically analyze the experimental data and the existing models and concludes that conclusions on α/ß-centers, PSII connectivity, and the assignment of FV/FM to the maximum PSII quantum yield may require critical re-evaluations.

Parameters of photosynthetic energy partitioning.

  • D. Lazár
  • Environmental Science
    Journal of plant physiology
  • 2015

A simple chlorophyll fluorescence parameter that correlates with the rate coefficient of photoinactivation of Photosystem II

It is concluded that Fs/Fm′, the ratio of steady-state to maximum fluorescence during illumination, is a simple predictor of kpi, which represents the quantum efficiency of combined non-photochemical dissipation pathways in active PS IIs.

Chlorophyll fluorescence: a probe of photosynthesis in vivo.

  • N. Baker
  • Environmental Science
    Annual review of plant biology
  • 2008
This review examines how fluorescence parameters can be used to evaluate changes in photosystem II (PSII) photochemistry, linear electron flux, and CO(2) assimilation in vivo, and outlines the theoretical bases for the use of specificfluorescence parameters.

Chlorophyll a Fluorescence: A Bit of Basics and History

The goal is to bring to the readers the basics of Chl fluorescence, a bit of history, it's potential in understanding primary photophysical events (excitation energy transfer; charge separation), and secondary reactions (electron transport).

NPQ(T) : a chlorophyll fluorescence parameter for rapid estimation and imaging of non-photochemical quenching of excitons in photosystem-II-associated antenna complexes.

A new set of parameters, NPQ(T) , and its components are derived and characterized that can be measured in a few seconds, allowing for high-throughput and field applications, and does not require full relaxation of quenching processes and thus can be applied to photoinhibited materials.

Potential errors in electron transport rates calculated from chlorophyll fluorescence as revealed by a multilayer leaf model.

  • J. R. Evans
  • Environmental Science
    Plant & cell physiology
  • 2009
A new approximation for phiPSII is used to generate fluorescence values to be generated at each layer in a multilayer model to show that when quantum yield varies through a leaf, then fluorescence will lead to an incorrect estimate of electron transport rate.

Estimation of the relative sizes of rate constants for chlorophyll de-excitation processes through comparison of inverse fluorescence intensities.

The paper derives a simple way to calculate the linear relationships between all separable groups of rate constants for de-excitation of Chl a excitation energy. This is done by comparison of the



Using chlorophyll fluorescence to assess the fraction of absorbed light allocated to thermal dissipa

In the present study we explored the possibility of assessing the allocation of photons absorbed by photosystem II (PSII) antennae to thermal energy dissipation and photosynthetic electron transport

Model for the fluorescence induction curve of photoinhibited thylakoids.

Fluorescence analysis during steady-state photosynthesis

Photosynthetic gas exchange of attached leaves has been measured under steady-state conditions at different light intensities and correlated with simultaneous measurements of chlorophyll fluorescence

Chlorophyll fluorescence as a nonintrusive indicator for rapid assessment of in vivo photosynthesis

In the past, ecophysiologically oriented photosynthesis research has been governed by gas-exchange measurements, mainly involving sophisticated (and costly) systems for simultaneous detection of CO2

High resolution imaging of photosynthetic activities of tissues, cells and chloroplasts in leaves.

Examples of heterogeneity of the operating quantum efficiency of PSII photochemistry during the induction of photosynthesis in maize leaves and in the chloroplast populations of stomatal guard cells of a leaf of Tradescantia albifora are presented, together with analyses of the factors determining this heterogeneity.

Resolving chlorophyll a fluorescence images of photosynthetic efficiency into photochemical and non-photochemical components – calculation of qP and Fv-/Fm-; without measuring Fo-;

Imaging of chlorophyll a fluorescence from leaves has enabled the spatial resolution of the fluorescence parameter, ΔF/Fm-;. Although this parameter provides a reliable estimate of photosynthetic

Quantum yields of photosystem II electron transport and carbon dioxide fixation in C4 plants.

The results suggest that in C4 plants both the photoreduction of O2 and photorespiration are low, even at very limiting CO2 concentrations, suggesting that photochemical use of energy absorbed by PS II is tightly linked to CO2 fixation in C 4 plants.