[Effect of total ginsenosides on protective enzymes of Mythimna separata larvae]

Under indoors simulating natural growing condition, the 4th-instar Mythimna separata larvae were fed by using poi- son leaf disk method. The effect of total ginsenosides on the protective enzymes (PPO, T-SOD, CAT and POD) of M. separata larvae was studied. The total ginsenosides could influence the protective enzymes of 4th-instar M. separata larvae significantly. After treated by total ginsenosides, the PPO activities increased firstly then decreased, and tended to equilibrium, and reached the maximum after 48 h. Furthermore, the total ginsenosides disturbed the dynamic balance of SOD, CAT and POD of M. separata larvae, and the yield of O2-* speeded. The results suggest that the total ginsenosides influence the protective enzymes of 4th-instar M. separata larvae, and disturb the original dynamic balance of protective enzymes. Consequently the insect suffers from the harm of O2-*.