关键词: 模拟酸雨, 芭蕉, 美人蕉, 抗氧化酶, 抗性机理

Abstract: [Objective] The objective of this study was to investigate the effects of simulated acid rain on visible damage and physiological traits of C. indica and M. basjooleaves.[Method] This experiment had four pH treatments,including pH 2.0,3.0,4.0 and 5.6 (control).Foliage damage was observed and malondialdehyde (MDA) content,superoxide dismutase (SOD),peroxidase (POD) and catalase (CAT) activities were analyzed after six stresses.[Results] Simulated acid rain of pH 2.0 had no significant influence on M. basjoo seedlings and no visible damage was observed.However,compared with M. basjoo,the injury symptoms in leaves of C. indica were much clearer.There were significant differences in MDA between treatments (pH 4.0 and pH3.0) and control irrespective of the species and effect size was greater for C. indica relative to M. basjoo.Antioxidative enzymes activities (SOD,POD and CAT) of M. basjoo and POD of C. indica increased with treatment time.There was pronounced difference in resistance to acid rain stress between the two species.M. basjoo and C. indica had different resistance and adjusting mechanisms.M. basjoo had advantageous anti-active oxygen systems,which can scavenge free radicals effectively to avoid injuring membrane lipid.[Conclusion] M. basjoo had higher resistance to acid rain when pH ≤ 3.0.Under the acid rain stresses,the main removal enzyme of reactive oxygen species was only POD.Therefore,a single enzyme activity was increased by acid rain,which may be responsible for small resistance of C. indica.

Key words: simulated acid rain, Musa basjoo, Canna indica, antioxidant enzymes, resistance mechanisms