Figure 3.

Split-root experiment analyzing the root specific effect of addition of a pulse of 500 μM P on Mn net uptake in a 53-day-old plant of the Mn-efficient genotype Vanessa as measured by on-line ICP-MS. Both root compartments were given a Mn pulse, followed by addition of a 500-μM P pulse to only one of the compartments. The experiment was repeated several times with similar results. The shoot weight was 6.93 g DW. The root weight was 1.36 g DW for the compartment pulsed with Mn only (circles) and 0.71 g DW of the other compartment receiving additional P. The two curves were normalized to equal root weight.