Abstract: 【Objective】The objective of this study is to compare the activities of defense enzymes in different tissues of winter jujube induced by the damage of Apolygus lucorum and artificial needling, and to observe the changes of stress defense activities of enzymes in leaves, buds, flowers and young fruits with different levels of damage by A. Lucorum. 【Method】The experiments were conducted with vulnerable jujube tissues inoculation, artificial simulated needling, counting damage spots after 24 hours, then the damaged tissues were sampled. The activities of SOD, POD and CAT were determined by nitroblue tetrazolium method, guaiacol method and ultraviolet absorbance method, respectively.【Result】The activity of defense enzymes was changed with different damages. The activities of SOD, POD and CAT in leaves induced by the damage of A. lucorum and artificial needling were significantly higher than the leaves without damage, and the activities of SOD and CAT induced by A. lucorum damage were significantly higher than the artificial needling. There was not significant difference among the SOD activities in buds without damage, and those damaged by A. lucorum and artificial needling, while POD activities were significantly increased with the damage of A. lucorum and artificial needling. CAT activity in buds induced by A. lucorum damage was significantly higher than needling ones. At the flowering stage, SOD and CAT activities had no significant difference while POD was significantly increased with the damage stress, and that induced by A. lucorum damage was significantly higher than needling ones. At the young fruiting stage, the POD activities which were induced by A. lucorum damage and artificial needling were significantly higher than those without damage. At the same time, SOD activity was significantly higher in A. lucorum damaged fruit, while CAT activity was statistically indifferent. These results indicated that the defense enzymes in the tissues of winter jujube varied at the damage stress. Stress defense enzyme activities of winter jujube differed to varied damage levels of A. lucorum. With increasing damage, SOD activities in leaves and flowers increased initially and then decreased, while the activities of POD and CAT increased. With the increase of damage level, SOD activity in buds was statistically indifferent, while that of POD and CAT increased significantly. With the increasing damage, SOD activity of young fruits decreased initially, and then increased, however, that of POD increased initially and then decreased. 【Conclusion】The damage of A. lucorum could induce a series of biochemical reactions in host-plants. The activities of SOD, CAT and POD in leaves and the activity of POD in the reproductive organs (buds, flowers and fruits) were much higher under the damage stress. Both physical and chemical damages of A. lucorum induced more defense enzymes than the artificial needling. Defense enzymes in different tissues of winter jujube showed variations with the increasing levels of damage.

Key words: Apolygus lucorum , winter jujube , damage , defensive enzymes