NaCl处理下黄花补血草幼苗生理特性的变化

以荒漠盐生植物黄花补血草(Limonium aureum(Linn.) Hill)为材料,研究不同浓度NaCl处理下渗透调节物含量、活性氧产生和抗氧化酶活性的变化。结果显示：NaCl处理诱导黄花补血草幼苗脯氨酸、可溶性糖和H2O2含量升高及超氧阴离子（O₂^-·）产生速率增大，可溶性蛋白含量在25和50 mmol·L^-1 NaCl处理时低于对照,而100和150 mmol·L^-1 NaCl处理时显著增加；不同浓度NaCl处理下，黄花补血草超氧化物歧化酶(SOD)和抗坏血酸过氧化物酶(APX)活性显著升高,过氧化物酶活性与对照比呈现先增加后减小的变化,而过氧化氢酶活性表现为先降低后升高的变化趋势,但均低于对照。结果表明，黄花补血草在盐胁迫下通过积累渗透调节物和提高SOD、APX活性,使其具有较强的渗透调节能力和抗氧化能力,从而增强对盐环境的适应性。

Changes of Physiological Properties in Limonium aureum(Linn.) Hill Seedlings under Salt Stress

In this study, desert halophyte Limonium aureum(Linn.) Hill was used to investigate the changes of osmolyte content, reactive oxygen species production and antioxidant enzyme activities in the leaves of seedlings under different NaCl concentrations. The levels of proline, soluble sugar and H₂O₂ as well as the rate of O₂^-· production increased in the seedlings treated with different NaCl concentrations. Compared with the control, the amount of soluble protein decreased in the leaves of seedlings treated with 25 and 50mmol·L^-1 NaCl, but enhanced under 100 and 150 mmol·L^-1 NaCl treatments. Additionally, all applied NaCl concentrations resulted in the enhancement of superoxide dismutase (SOD) and ascorbate peroxidase (APX) activities. In contrast, the activity of peroxidase increased at first and then decreased, but significant decrease in catalase activity was observed in the leaves of L.aureum treated with NaCl, as compared with the untreated seedlings. These results indicated that the accumulation of osmoregulation substances and the enhancements of SOD and APX activities in response to salt stress elevated the osmotic adjust action and the oxidation resistance ability in the leaves of L.aureum, which might be associated with the elevation of plant tolerance to salt condition.