Table I.

Fe(III) reduction activity and transfer cell frequency in split-root tomato wild-type plants

Root Treatment	Fe(III) Reduction	Transfer Cells
Iron-supplied split roots	1.63 ± 0.26	6.3 ± 1.2
Iron-deficient split roots	0.56 ± 0.30	28.1 ± 3.2

The reduction activity and the no. of transfer cells was determined 4 d after onset of the treatments. Reduction activity is expressed as μmol g⁻¹ fresh wt h⁻¹ ± sd, n = 5; transfer cell frequency is given as a percentage of the total rhizodermal cells ± sd.