Coordinative Effects of Salt and Alkali Stresses on Sunflower Antioxidative Enzymes
- VernacularTitle:盐碱协同胁迫对向日葵抗氧化酶系统的影响
- Author:
Yanmin SHENG
;
Jinzhi YIN
;
Decheng SHI
;
Deli WANG
- Publication Type:Journal Article
- Keywords:
alkali stress;
antioxidant enzyme;
salt stress;
salt alkaline mixed stress;
sunflower
- From:
Chinese Journal of Biochemistry and Molecular Biology
2008;24(8):704-711
- CountryChina
- Language:Chinese
-
Abstract:
Based on the characteristics of salt.alkalinized soil in northeastem China,twenty-five kinds of salt alkaline conditions with different salinities and pH were simulated by mixing NaCl,NaHCO3,Na2SO4,and Na2CO3,in various proportions and applied to sunflower (Helianthus annuus L.) seedlings to investigate the coordinative effects of salt and alkali stresses on its antioxidant enzyme system.The soil was conditioned with a salt concentration range between 50 to 250 mmol/L and pH values from 7.12 to 10.46.Several physiological indexes of stressed seedlings were measured,including the activities of superoxide dismutase (SOD),catalase (CAT),and pemxidase (POD),as well as the content of malondialdehyde (MDA).The results showed that the responses of the antioxidant enzyme system in sunflowers were influenced by salinity and alkalinity,which all three antioxidant enzymes exhibited a rise-drop pattern as salinity increased,whereas their responses to alkalinity appeared to be diverse:decreased for SOD and CAT,and increase for POD along when increasing alkalinity.A two-way analysis of variance (ANOVA) showed that the effects of salinity and alkalinity on the activities of the three enzymes were significant (P＜0.001).The effect of salinity on POD and SOD was greater than that of alkalinity,whereas the effect of alkalinity on CAT was greater than that of salinity.The interrelation of salinity and alkalinity on each antioxidant enzyme was significant (P＜0.001) except for SOD.The correlation and stepwise regression analyses between the activity of the antioxidant enzyme system and the MDA content were significant to difierent extend,SOD was a dominant factor,and POD was neglectable.
