Figure 5.

The levels of reactive oxygen species (ROS) were measured in leaves of wild‐type and transgenic lines OE‐2 and OE‐5 inoculated with TMV‐green fluorescent protein (GFP) (at 3 days postinoculation, dpi). (a) The levels of ${\mathrm{O}}_2^{\bullet ‐}$ and H₂O₂ were determined by nitroblue tetrazolium (NBT) and 3,3′‐diaminobenzidine (DAB) staining of WT and transgenic lines OE‐2 and OE‐5 after TMV‐GFP infection. (b) H₂O₂ content was measured using a sensitive quantitative Amplex red hydrogen peroxide/peroxidase assay kit. (c) ${\mathrm{O}}_2^{\bullet ‐}$ content was examined by the hydroxylamine oxygenation reaction method. WT, nontransformed wild‐type Nicotiana benthamiana plants inoculated with 0.02 M phosphate‐buffered saline (PBS); OE‐2, α‐MMC‐transgenic N. benthamiana line 2 inoculated with 0.02 M PBS; OE‐5, α‐MMC‐transgenic N. benthamiana line 5 inoculated with 0.02 M PBS; WT + TMV‐GFP, leaves of nontransformed WT N. benthamiana plants inoculated with TMV‐GFP (at 3 dpi); OE‐2 + TMV‐GFP, leaves of α‐MMC‐transgenic N. benthamiana line 2 inoculated with TMV‐GFP (at 3 dpi); OE‐5 + TMV‐GFP, leaves of α‐MMC‐transgenic N. benthamiana line 5 inoculated with TMV‐GFP (at 3 dpi). Bars represent mean and SD of values obtained from three biological replicates. Significant differences (p < .05) are denoted by different lowercase letters