Studies on the Changes of Superoxide Dismutase,Peroxidase and Polyphenoloxidase in Seed Coat of Soybeans after Infected with Soybean Mosaic Virus

Resistant and susceptible soybean varieties were inoculated with Soybean Mosaic Virus(SMV). The seeds were taken for biochemical analysis . The results showed that both peroxidase (POD) and polyphenoloxidase (PPO) activities in seed coat of uninoculated resistant varieties were much higher than those of uninoculated susceptible varieties. Superoxide dismutase (SOD) activity in seed coat of uninoculated resistant varieties was a little stronger than that of susceptible varieties. There were two more bands of PPO and three more bands of POD in uninoculated resistant varieties than those in susceptible varieties. After inoculated with SMV,POD activity was increased a little in susceptible varieties. Both POD and PPO activities were rapidly decreased in seed coat of resistant varieties after inoculated with SMV and one band was vanished. SOD activity was increased in susceptible varieties after inoculated with SMV, while it remained stable in resistant varieties.