水涝胁迫下烟草对水杨酸和硝普钠的生理响应

Physiological Responses of Tobacco to Salicylic Acid and Sodium Nitroprusside under Waterlogging Stress

【目的】为了探明涝害胁迫下烟草对水杨酸(SA)和硝普钠(SNP)的生理响应,揭示SA和SNP对提高烟草耐涝性的生理机制。【方法】通过人工模拟水涝胁迫,研究SA和SNP单独和复合处理对烟草根冠比、根系活力、叶绿素含量、渗透调节物质及膜脂过氧化系统的影响。【结果】水涝胁迫下,SA和SNP可提高根冠比和根系活力,减缓叶绿素和类胡萝卜素含量的下降幅度;使叶片积累更多的可溶性糖、可溶性蛋白质和游离脯氨酸,增强细胞的渗透调节能力。SA和SNP还能提高涝害短期胁迫下SOD和POD的活性,延缓长期胁迫下酶活性的下降,降低过氧化氢的含量和氧自由基产生速率,进而降低丙二醛含量和相对电导率,增强烟草对水涝胁迫的适应性。【结论】生产上可用SA和SNP复合处理来缓解水涝胁迫对烟草的伤害,SA和SNP复合处理的效果最佳。

[Purpose]The physiological response of tobacco to salicylic acid(SA)and sodium nitroprusside(SNP)under waterlogging stress was investigated,and the physiological mechanism of SA and SNP to improve the waterlogging tolerance of tobacco was revealed.[Method]Through artificial simulation of waterlogging stress,the effect of SA and SNP only and combined treatments on the tobacco root shoot ratio,root activity,chlorophyll content,osmolytes and lipid peroxidation system were studied.[Result]Under waterlogging stress,SA and SNP could improve the root shoot ratio and root vigor and slow down the decrease of chlorophyll and carotenoid contents;it could increase the cumulation of soluble sugar,soluble protein and free proline,and enhance the osmotic adjustment ability.SA and SNP could improve SOD and POD activities under short-term waterlogging stress,delay the decrease of the enzyme activities under long-term stress,reduce the content of hydrogen peroxide and oxygen free radical production rate,and further decrease MDA content and relative conductivity,enhance tobacco to waterlogging stress adaptability.[Conclusion]The production is available on the SA and SNP combined treatment to alleviate the waterlogging stress on tobacco harm,SA and SNP combined treatment has the best effect.