以盐生植物黄花补血草幼苗为供试材料，研究了不同浓度NaCl（0，25，50，100，150 mmol・L －1）胁迫下叶片抗坏血酸‐谷胱甘肽（AsA‐GSH）循环中抗氧化物质含量和抗氧化酶活性的变化。结果显示：150 mmol・L －1 NaCl处理诱导幼苗叶片AsA和总抗坏血酸含量增加；所有盐浓度诱导脱氢抗坏血酸（DHA）含量、GSH／氧化型谷胱甘肽（GSSG）比值升高，谷胱甘肽还原酶（GR）、抗坏血酸酶（AAO）和脱氢抗坏血酸还原酶（DHAR）活性增强，而AsA／DHA比值、GSSG含量和单脱氢抗坏血酸还原酶（MDHAR）活性降低。此外，低浓度盐胁迫下幼苗叶片GSH含量升高，而高浓度盐处理诱导叶片GS H含量降低。表明盐胁迫下黄花补血草幼苗叶片提高了非酶抗氧化物质含量和抗氧化酶活性，增强了幼苗清除活性氧的能力，增强了对盐胁迫的耐受能力。%Halophyte Limonium aureum (L ) Hill seedlings are used to investigate the changes of antioxidant substance contents and antioxidant enzyme activities associated with ascorbate‐glutathione (AsA‐GSH) cycle in respones to different NaCl concentrations (0 ,25 ,50 ,100 ,150 mmol・L -1 ) . The amount of ascorbic acid (AsA ) and total ascorbic acid contents rise due to only 150 mmol・L -1 NaCl . Differently ,all salinity concentrations lead to the increases of dehydroascorbate(DHA) content ,GSH/oxidized glutathione(GSSG) and glutathione reductase(GR) , ascorhic oxidas(AAO) and dehydroascorbate reductase(DHAR) activities ,but the decreases of AsA/DHA , GSSG level and monodehydroascorbate reductase ( MDHAR ) activities . In addition , GSH content increases in response to low NaCl concentrations but decreases to high salinity in the leaves of Limonium aureum(L) Hill seedlings . Taken together , salinity stress results in the increases of non‐enzymatic antioxidant levels and antioxidant enzyme activities in the leaves of Limonium aureum(L) Hill seedlings ,which might enhance the ability of reactive oxygen species scavenging and strengthen seedling resistance to salt stress .
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