Fig. 5

Antioxidant enzymatic activities during pathogen stress. Nicotiana tabacum plants were grown for 60 days in the greenhouse, thereafter, the plants were treated with either the plant pathogen Pseudomonas syringae pv tabaci (Pst) which is virulent in Nicotiana tabacum, the avirulent strain Pseudomonas syringae pv phaseolicola (Psp), mechanical wounding, MgCl₂ as a control or untreated plants. Leaves were harvested at 2, 8, 24 and 48 h after treatment and the enzymatic activities of the ten antioxidant scavenging enzymes were tested and normalized by fresh weight. Bars indicate standard deviations of three independent biological replicates