Changes of Related Defense Enzyme Activity in Resistance to Melon Powdery Mildew
Zhao Guangwei, Xu Yongyang, Xu Zhihong, Zhang Jian, Kong Weihu(Zhengzhou Fruit Research Institute, Chinese Academy of Agricultural Sciences, Zhengzhou 450009)
The change of defense enzyme activity in the resistant reaction to melon powdery mildew were studied through determined the perroxidase(POD), catlase(CAT)and Polyphenoloxidase(PPO) activity after artificial inoculation. The results showed that the activity of POD、CAT and PPO had no obvious difference between resistance and susceptible control. Activity of the three kind enzymes had increased after inoculating compared with their control. CAT activity of the resistant variety was higher than the susceptible variety. The case of POD activity is opposite to CAT. PPO activity of resistant variety was exceeded than susceptible variety until five days after inoculation.