Fig. 1.
Effects of mechano-stimulation on chlorophyll a fluorescence transient of dark adapted leaves (the latest fully expanded leaves) in winter wheat exposed to cold stress at jointing. (a & c) fluorescence intensity on logarithmic time scale; b & d WIP = (Ft-FI)/(FP-FI), ratio of variable fluorescence Ft-FI to the amplitude FP-FI; (e & g) WOP = (Ft-FO)/(FP-FO), ratio of variable fluorescence Ft-FO to the amplitude FP-FO; (f & h) WOI = (Ft-FO)/(FI-FO), ratio of variable fluorescence Ft-FO to the amplitude FI-FO