Figure 1.

Detection of nitric oxide (NO) in maize roots using confocal microscopy. The effect of exogenously applied NO (10 μM DETA/NO) and salt stress (150 mM NaCl) on maize root NO content were measured. Bright field (A and A1–A7), fluorescence (B1–B7) and merged (C and C1–C7) micrographs of later root sections (100 μm) are shown. Root sections were obtained 21 d after treatment with NO and salt stress. DAF-2 DA fluorescent triazole derivative fluorescence was measured following pre-incubation with 400 μM cPTIO (B2), treatment with 10 μM DETA (B3), 10 μM DETA/NO (B4), 150 mM NaCl (B5), 10 μM DETA + 150 mM NaCl (B6), 10 μM DETA/NO + 150 mM NaCl (B7). As a control, autofluorescence at the same settings was also measured from roots, obtained from untreated plants, which were not stained with DAF-2 DA (B1). Micrographs are representative of three independent experiments. Red bar = 100 μm.