| 摘要: |
| 【目的】探讨等渗盐胁迫下外源亚精胺(Spd)对番茄幼苗抗氧化系统的影响。【方法】采用水培法，以盐敏感型番茄品种‘中杂9号’为材料，以150 mmol/L NaCl和100 mmol/L Ca(NO3)2模拟等渗盐胁迫环境，设置5个处理，分别为：对照.1/2倍Hoagland营养液+叶面喷水；单独NaCl处理.150 mmol/L NaCl溶液+叶面喷水；单独Ca(NO3)2处理.100 mmol/L Ca(NO3)2溶液+叶面喷水；NaCl+Spd处理.150 mmol/L NaCl溶液+叶面喷0.25 mmol/L Spd；Ca(NO3)2+Spd处理.100 mmol/L Ca(NO3)2溶液+叶面喷0.25 mmol/L Spd，研究等渗盐胁迫下外源Spd对番茄幼苗生物量,超氧阴离子自由基（O-·2）、过氧化氢（H2O2）、丙二醛（MDA）含量,相对质膜透性及抗氧化酶（SOD、POD、CAT、APX）活性的影响。【结果】与对照相比，等渗NaCl、Ca(NO3)2胁迫下，番茄幼苗生物量和SOD、POD、CAT、APX活性均显著降低，相对质膜透性、MDA、O-·2和H2O2含量均显著增加。与单独NaCl或Ca(NO3)2胁迫相比，2种盐胁迫下再喷施Spd后明显增加了番茄幼苗生物量和抗氧化酶活性，显著降低了相对质膜透性、MDA、O-·2和H2O2含量，且外源Spd对NaCl胁迫的调控效应更为显著。【结论】外源Spd可通过提高抗氧化酶活性来增强番茄幼苗清除体内活性氧（ROS）及降低膜透性的能力，缓解盐胁迫对番茄幼苗生长的抑制作用，从而提高番茄抗盐性。单独Ca(NO3)2胁迫下植物受到的氧化伤害程度低于单独NaCl胁迫。 |
| 关键词: 亚精胺 等渗盐胁迫 番茄 抗氧化系统 |
| DOI： |
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| 基金项目:国家自然科学基金青年科学基金项目（31101581）；山西农业大学引进人才博士科研启动费项目（2014YJ21） |
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| Effects of exogenous spermidine on antioxidant system of tomato seedlings under isotonic salt stress |
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PAN Yuanyuan,ZHANG Yi,SHI Yu,et al
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| Abstract: |
| 【Objective】This study aimed to investigate the regulation effects of exogenous spermidine (Spd) on antioxidant system of tomato (Solanum lycopersicum L.) seedlings under isotonic salt stress.【Method】The salt sensitive tomato variety (‘Zhongza 9’) was treatment with isotonic saline stress simulated by 150 mmol/L NaCl and 100 mmol/L Ca(NO3)2.Five treatments were set including the control (half-strength Hoagland’s nutrient solution cultivation and sprayed with distilled water),single NaCl treatment (seedlings were exposed to half strength Hoagland’s nutrient solution containing 150 mmol/L saline solution and sprayed with distilled water),single Ca(NO3)2 treatment (seedlings were exposed to half-strength Hoagland’s nutrient solution containing 100 mmol/L saline solution and sprayed with distilled water),NaCl+Spd treatment (seedlings were exposed to half-strength Hoagland’s nutrient solution containing 150 mmol/L saline solution and sprayed with 0.25 mmol/L Spd) and Ca(NO3)2+Spd treatment (seedlings were exposed to half-strength Hoagland’s nutrient solution containing 100 mmol/L saline solution and sprayed with 0.25 mmol/L Spd).Then,the effects of foliar-spraying Spd on biomass,contents of superoxide anion radica (O-·2),hydrogen peroxide (H2O2) and malondialdehyde (MDA),relative plasma membrane permeability and activities of antioxidant enzymes (SOD,POD,CAT,and APX) were analyzed.【Result】Compared with the control,the biomass and activities of SOD,POD,CAT and APX of tomato seedlings decreased significantly, while the relative plasma membrane permeability and contents of MDA,O-·2 and H2O2 increased significantly under isotonic NaCl and Ca(NO3)2 stress.In comparison with the single NaCl treatment or Ca(NO3)2 treatment,spraying Spd increased the biomass and antioxidant enzyme activities of tomato seedlings significantly but reduced the relative plasma membrane permeability and contents of MDA,O-·2 and H2O2 significantly.The effect of exogenous Spd on regulation of NaCl stress was more significant.【Conclusion】Exogenous Spd could improve antioxidant enzyme activities to enhance the scavenging ability of reactive oxygen species (ROS) and decrease membrane permeability of tomato seedlings.Thus,the inhibitory of salt stress on growth was alleviated and the salt resistance of tomato seedlings was improved.The oxidative damage degree of plants under single Ca(NO3)2 stress was lower than under single NaCl stress. |
| Key words: exogenous spermidine isotonic salt stress tomato antioxidant system |
