外源钙和NO对盐胁迫下梨保护酶的影响

Effects of exogenous calcium and nitric oxide on pear protective enzymes under salt stress

【目的】为探明提高梨对盐生环境适应性的途径。【方法】以组织培养愈伤组织为试材,进行NaCl胁迫处理,检测保护酶活性的变化,并用外源CaCl_2和NO处理耐盐性弱的愈伤组织材料分析其对盐胁迫下保护酶活性的影响。【结果】在NaCl胁迫下,杜梨的SOD、POD和APX酶活性均为先上升后下降的趋势,CAT酶活性在处理6h时虽下降但之后快速上升;雪花梨四种酶活性均呈下降趋势。外源CaCl_2和SNP处理可以显著提高NaCl胁迫下雪花梨SOD、POD和CAT酶活性,而对APX酶活性影响不显著。【结论】与杜梨相比,雪花梨保护酶系统对NaCl胁迫的响应不敏感,而外源钙和一氧化氮可以通过激活特定的保护酶系统以增强其耐盐性。

【Objective】To explore the regulation of exogenous CaCl2 and NO on pear of salt tolerance.【Methods】The callus in tissue culture was used as materials,the changes of protective enzymes activities triggered by NaCl stress were determined.Then the salt-sensitive callus was treated with exogenous CaCl2 and NO to investigate their effects on protective enzymes activities.【Results】The activities of SOD,POD and APX in Pyrus betulaefolia Bunge showed the tendency of rising followed by falling under NaCl stress,the activities of CAT decreased after 6 hours of treatment,then increased rapidly.The activities of all four protective enzymes in Pyrus bretschneideri (‘Xuehua’ pear) decreased gradually.The SOD,POD and CAT activities of ‘Xuehua’ pear were significantly increased when exogenous CaCl2 and SNP were added under NaCl stress,APX activities was no significantly affected.【Conclusion】The Pyrus betulaefolia Bunge had stronger protective enzyme system compared with ‘Xuehua’ pear.Exogenous calcium and nitric oxide could enhance salt tolerance of ‘Xuehua’ pear by activating its specific protective enzyme system.