Fig. 5

Maps of chlorophyll fluorescence kinetics parameters before and after the µXRF experiment in vivo. A 5 × 5 mm area of a pepper (C. annuum, cultivar ‘Kozy Roh’) leaf was measured in a single cycle with 600 ms integration time per point and 15 µm point distance. This resulted in an approx. 20 h total measuring time. The µXRF measurements for these leaves are shown in Fig. 8. Φ_Po—maximum quantum yield of primary PSII photochemistry, Φ_ET2o—quantum yield of the electron transport flux from Q_A to Q_B, and Φ_RE1o—quantum yield of the electron transport flux until PSI electron acceptors, NPQ_{_i1} complete non-photochemical quenching (NPQ = (F_m − \( {\text{F}}_{\text{m}}^{{\prime }} \))/\( {\text{F}}_{\text{m}}^{{\prime }} \)) at the onset of irradiance