Table 5.
Summary of parameters, formulae and their descriptions using data extracted from the OJIP test
| Fluorescence parameters | Fluorescence parameters description |
|---|---|
| Extracted parameters |
|
| Ft |
Fluorescence intensity at time t after onset of actinic illumination |
| F50 μs |
Minimum reliable recorded fluorescence at 50 μs with the Handy PEA |
| Fk (F300 μs) |
Fluorescence intensity at 300 μs |
| FP |
Maximum recorded (=maximum possible) fluorescence at P-step |
| Area |
Total complementary area between fluorescence induction curve and F = Fm |
| Derived parameters |
|
| Fo ≌ F50 μs |
Minimum fluorescence, when all PSII RCs are open |
| Fm = FP |
Maximum fluorescence, when all PSII RCs are closed |
| Vj = (Fj - Fo)/(Fm - Fo) |
Relative variable fluorescence at the J-step (2 ms) |
| Vi = (Fi - Fo)/(Fm - Fo) |
Relative variable fluorescence at the I-step (30 ms) |
| WK = (Fk - Fo)/(Fj - Fo) |
Representing the damage to oxygen evolving complex (OEC) |
| Mo = 4 (Fk - Fo)/(Fm - Fo) |
Approximated initial increment (in ms-1) of the relative variable fluorescence |
| Fv/Fm = 1- (Fo/Fm) |
Maximum quantum yield of primary photochemistry at t = 0 |
| φEo = ETo/ABS = (Fm-Fj)/Fm |
Quantum yield for electron transport at t = 0 |
| RCQA = φPo × (ABS/CSm) × (Vj/Mo) | Amount of active PSII RCs (QA-reducing PSII reaction centers) per CS at t = m |