Table 3. OJIP parameters calculated from the P&P imaging and nonimaging measurements

Values represent medians ± se (n = 5 different plants). Asterisk signs denote significant differences between the two groups according to the Mann-Whitney test (*P < 0.05), which was done as a comparison of two methods: P&P imaging and nonimaging. Parameter definitions according to Stirbet and Govindjee (2011): VI/J, relative variable fluorescence at the I/J step; Mo, approximate value of the initial slope of relative variable Chl fluorescence curve Vt; ΦPo, maximum quantum yield of primary PSII photochemistry (equals Fv/Fm); ABS/RC, absorption flux/effective antenna size of an active reaction center; TRo/RC, trapped energy flux leading to a reduction of QA; ET2o/RC, electron transport flux further than QA; DIo/RC, dissipation flux.

ParameterP&P ImagingNonimaging
Vj0.46 ± 0.0080.478 ± 0.005
Vi0.9 ± 0.010.854 ± 0.005*
Mo1.11 ± 0.0231.412 ± 0.031*
ΦPo0.820 ± 0.0020.830 ± 0.001
ABS/RC3.000 ± 0.0273.527 ± 0.047*
TRo/RC2.450 ± 0.0192.935 ± 0.037*
ET2o/RC1.310 ± 0.0231.526 ± 0.013*
DIo/RC0.530 ± 0.0110.592 ± 0.010*