(A) Enzymatic assay and (B) Northern Blot analysis of cytosolic ICDH in roots and leaves of cucumber plants during the progression of Fe deficiency treatment. Sampling was performed at 0, 1, 3, 7 days after Fe withdraw. ICDH control activity was 92 and 98 nmol NADPH mg-1 prot min-1, respectively for root and leaf (complete activity data are reported in Additional file 1). The meaning of the columns and the measurement units of enzymatic activities are as reported in Figure 2. Data are means ± SE (n = 4). In the case of significant difference (P<0.05) values with different letters are statistically different.