Figure 2.

frd3 mutant roots can appropriately regulate their iron deficiency responses in the absence of a shoot signal. Seedlings had the shoot portion removed prior to transfer to iron-sufficient (+Fe) or iron-deficient (−Fe) media with added Suc. The ferrozine method was used to quantitate root ferric chelate reductase 5 d after transfer. This experiment was repeated three times; a representative experiment is shown.