Table 1.
Photosynthetic parameters deduced by the JIP-test analysis of fluorescence transients.
| C | D | H | H+D | Definitions | |||||
|---|---|---|---|---|---|---|---|---|---|
| PI234881 | PI578718 | PI234881 | PI578718 | PI234881 | PI578718 | PI234881 | PI578718 | ||
| DATA EXTRACTED FROM THE RECORDED OJIP FLUORESCENCE TRANSIENT CURVES | |||||||||
| F0 = F20μs | 0.54b | 0.28a | 0.68a | 0.27a | 0.57b | 0.27a | 0.67a | 0.29a | Fluorescence at time t after onset of actinic illumination |
| FK | 1.17b | 0.63ab | 1.32a | 0.65a | 1.2953a | 0.60c | 1.33a | 0.61bc | Fluorescence value at 300 μs |
| FJ | 1.26b | 0.74a | 1.39a | 0.75a | 1.405a | 0.68b | 1.41a | 0.69b | Fluorescence value at the J-step (2 ms) of OJIP |
| FI | 1.73a | 1a | 1.69a | 1.02a | 1.79a | 0.89b | 1.68a | 0.88b | Fluorescence value at the I-step (30 ms) of OJIP |
| FP ≡ FM | 2.16a | 1.16a | 2.06a | 1.15a | 2.07a | 1.06b | 2.02a | 1.04b | Fluorescence value at the peak of OJIP test |
| M0 | 1.57b | 1.59b | 1.86a | 1.72a | 1.93a | 1.65ab | 1.91a | 1.72a | Approximate value of the initial slope of fluorescence transient curves |
| SPECIFIC ENERGY FLUXES (PER ACTIVE PSII REACTION CENTER) | |||||||||
| ABS/RC | 4.69b | 4.01b | 5.49a | 4.08b | 4.81b | 4.25ab | 5.48a | 4.48a | Absorbed photon flux per RC |
| TR0/RC | 3.50a | 3.04b | 3.63a | 3.13ab | 3.48a | 3.17ab | 3.57a | 3.2a | Trapped excitation flux (leading to QA reduction) per RC |
| ET0/RC | 1.94a | 1.45a | 1.77b | 1.41a | 1.54c | 1.53a | 1.66bc | 1.48a | Electron transport flux (further than QA-) per RC |
| RE0/RC | 0.93a | 0.57b | 1.04a | 0.48c | 0.65b | 0.7a | 0.93a | 0.69a | Electron flux reducing end electron acceptors at the PSI acceptor side, per RC |
| QUANTUM YIELDS AND EFFICIENCIES/PROBABILITIES | |||||||||
| φP0 ≡ TR0/ABS | 0.75a | 0.76a | 0.66b | 0.77a | 0.72a | 0.75ab | 0.65b | 0.72b | Maximum quantum yield for primary photochemistry, namely FV/FM |
| ψE0 ≡ ET0/TR0 | 0.55a | 0.48a | 0.49b | 0.45a | 0.44c | 0.48a | 0.46bc | 0.46a | Efficiency/probability with which a PSII trapped electron is transferred from QA to QB |
| φE0 ≡ ET0/ABS | 0.41a | 0.36a | 0.33b | 0.35ab | 0.32b | 0.36ab | 0.3b | 0.33b | Quantum yield of the electron transport flux from QA to QB |
| δR0 ≡ RE0/ET0 | 0.48b | 0.39b | 0.59a | 0.34c | 0.42b | 0.46a | 0.56a | 0.47a | Efficiency/probability with which an electron from QBis transferred until PSI acceptors |
| φR0 ≡ RE0/ABS | 0.2a | 0.14b | 0.19a | 0.12c | 0.136c | 0.16ab | 0.17b | 0.17a | Quantum yield for reduction of end electron acceptors at the PSI acceptor side |
| γRC | 0.18a | 0.2a | 0.15b | 0.19a | 0.17a | 0.19ab | 0.15b | 0.18b | Probability that a PSII Chl molecule functions as RC |
| RC/ABS | 0.21a | 0.25a | 0.18b | 0.25ab | 0.20a | 0.24ab | 0.18b | 0.23b | Number of QA reducing RCs per PSII antenna Chl |
| PERFORMANCE INDEXES (PI, COMBINATION OF PARAMETERS) | |||||||||
| PIABS | 0.79a | 0.73a | 0.36b | 0.67ab | 0.44b | 0.66ab | 0.30b | 0.52b | PI (potential) for energy conservation from exciton to the reduction of intersystem electron |
| PItotal | 0.72a | 0.48a | 0.50b | 0.35b | 0.33c | 0.56a | 0.38c | 0.44ab | PI (potential) for energy conservation from exciton to the reduction of PSI end acceptors |
The calculation of each parameter is based on the method described by Yusuf et al. (2010). Subscript “0” indicates that the parameter refers to the onset of illumination. Values are given as the average of 4 replicates, and different letters indicate statistical difference significance at P < 0.05 among the treatments by Duncan's multiple range tests.