Study On The Relationship Between The Host Defensive Enzymes And Poplar Canker In The Extreme Climate

In this study,seven kinds of the host defense enzyme in the Populus simonii×Pnigra and the healthy were determined by UV spectrophotometry.The results showed that:(1)Under the two treatments,the activities of CAT were the highest one at 9 h,and the activity of CAT was 30.7%lower than that of healthy black poplar.(2)The activities of SOD in the leaves of Populus simonii×Pnigra were the highest at 9 h after low temperature induction,and the activity of Populus simonii×Pnigra was decreased by 26.7%.After high temperature ltreatment,the activities of SOD in the infected one were the highest at 7 h,and the activity of Populus simonii×PRnigra was 51.5%lower than that of the healthy.(3)The activity of PPO reached the highest at 3 h after the induction of low temperature,and the activity of Populus simonii×P.nigra was increased by 148%compared with the activity.After high temperature treatment,the activity of PPO reached the maximum at 7 h,and the activity of Populus simonii×P.nigra was increased by 1488%.(4)After inoculation,the activity of TI in the larvae of Populus simonii×P.nigra reached the maximum at 5 h,and the activity of Populus simonii xP.nigra was increased by 48.37%.After high temperature treatment,the activity of TI in the larvae of Populus simoniivP.nigra reached the maximum at 3 h,and the activity of Populus simonii×P.nigra was increased by 33.34%.(5)After inoculation,the activity of CI was the highest at 1 h,and the activity of Populus simonii×P.nigra was increased by 21.43%.After high temperature treatment,the activity of CI in the larvae of Populus simonii×P.nigra reached its maximum at 3 h,and the activity of Populus simonii×P.nigra increased by 22.71%.