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2. Photochemical and non-photochemical quenching coefficients of the chlorophyll fluorescence: comparison of variation and limits

Creator:
Buschmann, C.
Format:
bez média and svazek
Type:
model:article and TEXT
Subject:
pulse-amplitude-modulation
Language:
Multiple languages
Description:
There are several types of quenching coefficients currently in use which describe the decrease of the chlorophyll fluorescence: the photochemical quenching coefficients qP and q(P)rel and the non-photochemical quenching coefficients qN, q(N)rel, and NPQ. These five coefficients were calculated for a broad variety of cases of the fluorescence signals in a normal, realistic range and for determining the limits in a range with extremely low and high fluorescence values. The calculations showed that the quenching coefficients currently in use are not only numbers between 0 and 1 as one would expect when taking them as a relative measure of the quenching process. Most quenching coefficients must be regarded and interpreted carefully separated from each other. Each photochemical quenching coefficient and each non-photochemical quenching coefficient describe the same fluorescence signal in a different way. Only the relative quenching coefficients q(P)rel and q(N)rel match together and can be used to demonstrate a shift of the energy de-excitation from the photochemical to the non-photochemical route.
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public