Analysis Function of Different Defense Enzymes on Maize

The activities of peroxidase(POD), phenylalanine ammonia lyases(PAL), Ascorbate Peroxidase, superoxide dismutase(SOD) and catalase(CAT) were measured in R15 and 478 both in sheathes and leaves inoculated with AG1- IA or not inoculated. The results showed that as to resistant material(R15), the activities of POD, CAT, SOD, APX increased and PAL kept stable in sheaths, in leaves the activity of POD, CAT and APX increased, SOD, PAL decreased. As to high susceptible material(478), the activities of POD and CAT increased in both sheaths and leaves, SOD increased in leaves but decreased in sheathes, both PAL and APX had no striking change. Generally speaking, the POD and CAT activities of maize were positively related to its resistance. Experimental results suggested that these defense enzymes functioned in differential areas and courses in plant accomplished defense reactions.