Table A1.
Definition of selected OJIP parameters according to Strasser et al. [14] and Stirbet and Govindjee [15].
| Parameter | Definition |
|---|---|
| FO | Minimal fluorescence, when all PSII reaction centers (RCs) are open, fluorescence intensity at 20th µs |
| FM = FP | Maximal fluorescence recorded under saturating illumination at the peak P of OJIP, when all PSII RCs are closed |
| FJ (2 ms) | Fluorescence level at 2nd ms, the J-step of OJIP |
| FI (40 ms) | Fluorescence level at 40th ms, the I-step of OJIP нa гpaφикaтa e 40-тa ms |
| FV | Maximal variable fluorescence, FV = FM − FO |
| Vt | Relative variable fluorescence at time t: Vt = (Ft − FO)/(FM − FO) |
| VL | Relative fluorescence value at L-step [0.15 ms] |
| VK | Relative fluorescence value at K-step [0.3 ms] |
| N | Number indicating how many times QA is reduced until fluorescence reaches its maximal value FM (number of QA redox turnovers until FM is reached) |
| ABS | Absorbed energy flux (exited PSII antennae Chl a molecules) |
| TR0 | Trapped energy, i.e., energy, utilized for reduction of pheophytin and primary quinone acceptor QA |
| ET0 | Electron transport from QA– to the next electron acceptors between the two photosystems. |
| RE0 | Energy/electron flux for reduction of end acceptors in acceptor side of PSI—NADP and ferredoxin. |
| φEo (ET0/ABS) | Efficiency/probability for the electron in PSII to move further than QA–—quantum yield for electron transport. φEo = ET0/ABS = φPo × ψ0 = (1 − F0/FM) × ψ0 |
| ABS/RC | Absorbed energy flux in antenna chlorophylls per PSII reaction center (a measure of PSII apparent antenna size) |
| TR0/RC | Trapped energy flux per RC; TR0/RC = M0 (1/VJ) |
| ET0/RC | Electron transport flux further than QA– per PSII reaction center |
| RE0/RC | Electron flux reducing end electron acceptors at the PSI acceptor side, per PSII reaction center |
| DI0/RC | Heat dissipation of excitation energy by PSII reaction center |
| ET0/RC | Electron transport flux further than QA– per PSII reaction center |
| φPo (TR0/ABS) | Maximum quantum yield of primary photochemical reactions in PSII RC. φPo = TR0/ABS = 1 − FO/FM = FV/FM |
| φRo (RE0/ABS) | Quantum yield of the electron transport from QA– to the end electron acceptors of PSI RE0/ABS = φRo = φPo × ψ0 × δ0 |
| RC/CS0 | Density of active PSII reaction centers (RC) per cross section RC/CS0 = φPo × (VJ/M0) × (ABS/CS0) |
| PIABS | Performance index (potential) for conservation of the energy absorbed by PSII RC until the reduction of intersystem electron acceptors |
| PItotal | Performance index (potential) for conservation of the energy absorbed by PSII until the reduction of PSI end electron acceptors |