Table 1. OJIP parameters calculated from the direct fast imaging and P&P imaging 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, **P < 0.01), which was done as a comparison of two methods: Direct fast imaging and P&P imaging. Parameter definitions according to Stirbet and Govindjee (2011): V_I/J, relative variable fluorescence at the I/J step; M_o, approximate value of the initial slope of relative variable Chl fluorescence curve V_t; Φ_Po, maximum quantum yield of primary PSII photochemistry (equals F_v/F_m); ABS/RC, absorption flux/effective antenna size of an active reaction center; TRo/RC, trapped energy flux leading to a reduction of Q_A; ET2o/RC, electron transport flux further than Q_A; DIo/RC, dissipation flux.

Parameter	Direct Fast Imaging	P&P Imaging
Vj	0.510 ± 0.005	0.46 ± 0.008**
Vi	0.830 ± 0.004	0.9 ± 0.01*
Mo	1.400 ± 0.028	1.11 ± 0.023*
ΦPo	0.820 ± 0.002	0.820 ± 0.002
ABS/RC	3.37 ± 0.048	3.000 ± 0.027*
TRo/RC	2.780 ± 0.035	2.450 ± 0.019*
ET2o/RC	1.37 ± 0.009	1.310 ± 0.023
DIo/RC	0.600 ± 0.015	0.530 ± 0.011*