CAT and infection: Khajuria and Ohri [63] also observed that nematode infection of tomato plants increased the activity of SOD, CAT, POD, GPOX, etc. During the present study, the antioxidant enzymes and non-enzymatic antioxidants of tomato plants increased following infection with M. enterolobii at an inoculum density ranging from 500 to 2000 J2s per plant.