Histochemical staining by nitro blue tetrazolium (NBT) and diaminobenzidine (DAB) to reveal accumulation of O
- and H
in leaves of wild type (WT), transgenic lines (#4 and #19) subjected to 90-min dehydration or 21-d water stress. (A-B) Representative photos showing accumulation of O2- (A) and H2O2(B) in leaves before (0) and after 90-min (90) dehydration. (C) Representative photos showing accumulation of O2- (upper panel) and H2O2(lower panel) in leaves of plants after 21- d water stress.