Fig. 1.

Sulphate content in the flow-through solution during sulphur depletion treatment. Before starting sulphur depletion treatment, each plant pot was flushed three times with 1/10 diluted sulphur depletion medium (0 d). Solid (control) and dashed (sulphur depletion treatment) lines indicate approximated sulphate contents in the flow-through solution after watering the pots with full nutrient solution (filled triangle) or sulphur-free media (white circles), respectively. Each symbol represents one measurement which was collected as a mixture from the flow-through solution of five plants standing together in one tray.