Fig. 3

a Chl a fluorescence OJIP curves presented by treatments and environments (mean of replicates (24 ≤ n ≤ 45)). b F_V/F_M values results calculated from Chl a fluorescence curves under different spraying treatments, and standard error over replicates are plotted with error bar. Finally, the plot (c) shows the Mn concentration in μg.g⁻¹ of DW leaf tissue. In green, barley plants as controls did not receive any treatment application; in red, plants were sprayed with MnSO₄ solution