Figure 4. Element concentration ratios (means at different developmental stages divided by seed grain) as functions of developmental stage (BBCH) in winter wheat field-grown in monoculture in Central Sweden during the two growing seasons (2013 open symbols; and 2014 closed symbols; for graphical clarity, only the means for each developmental stage and year are reported).

Quadratic functions were fitted to most of the data, except Fe for which a power function was fitted. Note the different y-axis scales.