Table 2 The JIP-test parameters, along with their respective abbreviations, formulas, and definitions, are presented

BASIC PARAMETERS CALCULATED FROM THE EXTRACTED DATA

 FO \(\cong\) F50µsor \(\cong\) F20µs

fluorescence when all PSIIRCs are open (\(\cong\) to the minimal reliable recorded fluorescence) [39]

 T_FM=tF_MAX, t for F_M

Time (in ms) to reach maximal fluorescence Fm [39]

 FM(=FP)

maximal fluorescence, when all PSIIRCs are closed (=FP when the actinic light intensity is above 500 µmol (photon) m^-2 s¹ and provided that all RCs are active as QA-reducing) [39]

 FV \(\equiv\) FM – FO

maximalvariablefluorescence [39]

 SM \(\equiv\) Area/(FM – FO)=Area/FV

NormalisedArea to Fm [39]

 N =SM \(\times\) (MO/VJ)

Turnovernumber(expresseshowmanytimesQAisreducedinthetimeintervalfrom 0 to tF_M)  [39]

 V_J = (F_J – FO)/(F_M – FO)

Relative variable fluorescence at t = 2 ms [39]

 V_I = (F_I – Fo)/(F_M - Fo)

Relative variable fluorescence at t = 30 ms [39]

BIOPHYSICAL PARAMETERS DERIVED FROM THE BASIC PARAMETERS

 DeexcitationrateconstantsofPSIIantenna

  kN₌(ABS) \(\times\) kF \(\times\) (1/FM)

Nonphotochemical deexcitation rate constant (ABS: absorption flux - see below; kF: rate constant for fluorescence emission) [39]

  kP₌(ABS) \(\times\) kF \(\times\) (1/FO – 1/FM)=kN \(\times\) (FV/FO)

Photochemical deexcitation rate constant [39]

 Specific energy fluxes (perRC: QA-reducing PSII reactioncentre),inms-¹

  ABS/RC₌ MO \(\times\) (1/VJ) \(\times\) (1/φPo)

Absorption flux (exciting PSII antenna Chl a molecules) per RC (also used as a unit-less measure of PSII apparent antenna size) [39]

  TRO/RC ₌MO \(\times\) (1/VJ)

Trapped energy flux (leading to Q_A reduction), per RC [39]

  ETO/RC ₌MO \(\times\) (1/VJ) - (1-VJ)

Electron transport flux (further than Q_A^-), per RC [39]

  DIo/RC ₌ ABS/RC– TRo/RC

Dissipated energy flux per RC (at t = 0) [39]

 Phenomenologicalenergyfluxes(perCS:QA-reducingPSIIcrosssection),inms-¹

  TRO / CS_M=(Fv/F_M) (ABS/CS_M)

Trapped energy flux (leading to Q_A reduction) per RC (Tsimilli-Michael, 2020 [39])

  ETO / CS_M=(Fv/F_M) (1 - V_J) (ABS/CS_M)

Electron transport flux (further than Q_A^-) per RC (Tsimilli-Michael, 2020 [39])

  DIO / CS_M=(ABS/CSO) - (TRO/CSm)

Total energy dissipated per reaction center (RC) (Tsimilli-Michael, 2020 [39])

  ABS / CS_M=≈ Fo

Absorbed photon flux per excited PSII cross section at time zero [39]

 Quantumyieldsandefficiencies

  φPo=TR0/ABS=[1 - (FO/FM)]

Maximum quantum yield for primary photochemistry [39, 40]

  φEo=ET0/ABS=[1- (FO/FM)] (1-VJ)

Quantum yield for electron transport (ET) [41]

  ψEo=ET0/TR0=(1-VJ)

Efficiency/probability that an electron moves further than Q_A^- [41]

  ϕDo= Fo/Fm

Quantum yield (at t = 0) of energy dissipation [41]

 Performance indexes

\({PI}_{ABS}=\frac{1-({F}_{O}/{F}_{m})}{{M}_{O}/{V}_{j}}\times \frac{{F}_{m}/{F}_{o}}{{F}_{O}}\times \frac{1-{V}_{j}}{{V}_{j}}\)

Performance index for energy conservation from photons absorbed by PSII until the reduction of intersystem electron acceptors [39, 41]

\({PI}_{CS}=\frac{ABS}{CS} \times \frac{1-({F}_{O}/{F}_{m})}{{M}_{O}/{V}_{j}}\times \frac{{F}_{m}/{F}_{o}}{{F}_{O}}\times \frac{1-{V}_{j}}{{V}_{j}}\)

Performance index on cross section basis  [39, 41]