盐碱胁迫下外源H2O2对毛白杨生理特性的影响

研究外源H₂O₂对盐碱胁迫下毛白杨生理特性的影响规律,为提高毛白杨盐碱地造林效果提供理论依据。在盆栽条件下,设置营养液（对照,H1）、营养液+NaHCO₃+NaCl(H2)、营养液+NaHCO₃+NaCl+H₂O₂(H3)、营养液+H₂O₂(H4)4个处理,3次重复。结果表明,H2与H1相比显著提高了毛白杨超氧阴离子、过氧化氢、MDA含量及相对电导率,H3与H2相比显著降低了超氧阴离子、过氧化氢含量,相对电导率和MDA含量降低不显著,H4与H1之间无显著差异;H2与H1相比显著提高了SOD、POD、CAT、APX活性,提高了AsA和GSH含量,H3与H2相比提高了毛白杨保护酶活性和H₂O₂清除系统活性,H4与H1相比显著提高了毛白杨AsA含量;H2与H1相比显著提高了毛白杨可溶性糖含量,H3与H2相比降低了可溶性糖含量;H1与H2相比、H3与H2相比均提高了毛白杨可溶性蛋白和游离脯氨酸含量。综合分析认为,外源H₂O₂会激发毛白杨生理响应机制并缓解盐碱胁迫效果显著。

Effects of Exogenous H2O2 on Physiological Characteristics of Populus tomentosa Under Saline-alkali Stress

By studying the influence of exogenous H₂O₂ on physiological characteristics of Populus tomentosa under saline-alkali stress, the paper aims to provide a theoretical basis to improve the afforestation of P. tomentosa in saline-alkali land. Under potted condition, four treatments were set including nutrient solution (control, H1), nutrient solution+NaHCO₃+NaCl (H2), nutrient solution+NaHCO₃+NaCl+H₂O₂(H3), and nutrient solution+H₂O₂ (H4), which were repeated for 3 times. The results showed that: the content of superoxide anion, hydrogen peroxide, MDA and conductivity of P. tomentosa of H2 was significantly higher than those of H1, and the content of superoxide anion and hydrogen peroxide of H3 was significantly lower than those of H2, while the decrease of conductivity and MDA content was not significant, and there was no significant difference between H4 and H1; the activity of SOD, POD, CAT and APX of H2 was significantly higher than those of H1, increasing the content of AsA and GSH, H3 had an increase in the activity of protective enzyme and the activity of H₂O₂ scavenging system of P. tomentosa compared with H2, while H4 significantly increased the AsA content of P. tomentosa compared with H1; H2 significantly increased the content of soluble sugar of P. tomentosa compared with H1, while H3 decreased the soluble sugar content compared with H2; the content of soluble protein and free proline of P. tomentosa were increased by H1 compared with H2 and by H3 compared with H2. Through the comprehensive analysis, it is believed that exogenous H₂O₂ can stimulate the physiological response mechanism of P. tomentosa and alleviate salinity stress significantly.