Table 1. Description of chlorophyll-a fluorescence parameters.

Fluorescence parameters	Description
F0 = ABS/CS0	initial fluorescence obtained from measurements also denoted as ABS/CS0
F300	fluorescence at 300 μs after illumination of a dark-adapted sample
F2ms	fluorescence at 2 ms after illumination of a dark-adapted sample
F30ms	fluorescence at 30 ms after illumination of a dark-adapted sample
Fm	maximum fluorescence after illumination of a dark-adapted sample
VK = (F300 ‒ F0)/(Fm ‒ F0)	relative variable fluorescence at 300 μs after illumination of a dark-adapted sample
VJ = (F2ms ‒ F0)/(Fm ‒ F0)	relative variable fluorescence at 2 ms after illumination of a dark-adapted sample
VI = (F30ms ‒ F0)/(Fm ‒ F0)	relative variable fluorescence at 30 ms after illumination of a dark-adapted sample
ΔVIP = 1—VI	the efficiency of electron transport from PSII to PSI
M0 = 4 (F300 ‒ F0)/(Fm ‒ F0)	approximated initial slope of the fluorescence transient, expressing the rate of RCs’ closure
Fv/Fm = φPo = TR0/ABS = (Fm ‒ F0)/Fm	maximum quantum yield of PSII photochemistry
ψo = ET0/TR0 = (Fm−F2ms)/(Fm−F0)	probability that a trapped exciton moves an electron into the electron transport chain beyond QA,
δRo = RE0/ET0 = (Fm−F30ms)/(Fm−F0)	probability that an electron from the intersystem electron carriers is transferred to reduce end electron acceptors at the PSI acceptor side
RC/ABS = γRC/(1 –γRC) = φPo (VJ/M0)	QA reducing RCs per PSII antenna chlorophyll
RC/CS0 = φPo (VJ/M0) (ABS/CS0)	density of active RCs (.QA reducing RCs) per cross-sectioncross section at point 0
PIABS = RC/ABS × φPo/(1 –φPo) × ψEo/(1 –ψEo)	performance index (potential) for energy conservation from photons absorbed by PSII to the reduction of intersystem electron acceptors
PItotal = RC/ABS × φPo/(1 –φPo) × ψEo/(1 –ψEo) × δRo/(1 –δRo)	performance index (potential) for energy conservation from photons absorbed by PSII to the reduction of PSI end electron acceptors