The activities of five enzymatic antioxidant agents, including the superoxide dismutase (SOD), Catalase (CAT), Guaiacol peroxidase (GPX), Ascorbate peroxidase (APX), and Glutathione reductase (GR) were also investigated during infection with IPO323 and ΔAvrStb6#33. The gene discussed is CAT; the disease is infection.