摘要： 为探明外源H₂S和H₂O₂对NaCl胁迫下加工番茄幼苗的生理调节作用，以耐盐性弱的KT-32和耐盐性强的KT-7这2个加工番茄品系为材料，采用盆栽法，设置0.5，1.5，3.0 mmol/L 3个H₂O₂浓度水平，研究50 μmol/L H₂S和H₂O₂共处理对250 mmol/L NaCl胁迫下加工番茄幼苗的生长、渗透调节、物质积累和活性氧代谢的影响。结果表明，外源H₂S和H₂O₂共处理缓解了NaCl胁迫对加工番茄幼苗生长的抑制作用，使加工番茄幼苗仍保持较强的光合色素含量、较高的相对含水量和根系活力，降低了电解质渗出率、MDA含量、H₂O₂含量和O₂^·产生速率，增强了加工番茄幼苗叶片中抗氧化酶SOD、POD和CAT活性，其中在2个品系中，50 μmol/L H₂S和1.5 mmol/L H₂O₂共处理时可溶性糖分别比单独50 μmol/L H₂S处理提高了24.0%和29.4%，脯氨酸含量分别提高了25.8%和21.3%，缓解盐胁迫效果最为显著。综上，外源H₂S和H₂O₂之间存在着一定程度的协同作用，可以诱导增强NaCl胁迫下加工番茄幼苗植株渗透调节能力、提高清除活性氧的酶促系统的防御能力，从而减弱加工番茄细胞内活性氧自由基对质膜的伤害，进而提高加工番茄幼苗对盐胁迫的适应性。其结果可为探讨H₂S和H₂O₂ 这2种信号分子协同作用、缓解加工番茄幼苗盐胁迫的生理机制提供理论依据。

关键词: H₂O₂, H₂S, NaCl胁迫, 加工番茄幼苗

Abstract: The effects of exogenous H₂S and H₂O₂ physiological regulation on the processing tomato seedlings under NaCl stress were investigated,KT-32 with weak salt tolerance and KT-7 with strong salt tolerance as the materia. Research of 50 μmol/L H₂S and H₂O₂ were determined by pot culture under the conditions of 0.5,1.5,3.0 mmol/L. Effects of cotreatment on the growth,osmoregulation,material accumulation and reactive oxygen metabolism of seedlings of processed tomato under 250 mmol/L NaCl stress.The results showed that the cotreatment of exogenous H₂S and H₂O₂ alleviated the inhibitory effect of NaCl stress on the growth of seedlings of processed tomato seedlings,and maintained a strong photosynthetic pigment content,relatived water content and root activity in processed tomato seedlings.And decreased the electrolyte leakage rate,the content of MDA,the content of H₂O₂ and the production rate of O₂^· free radical and enhanced the activities of antioxidant enzymes SOD,POD and CAT activity. Among the two strains,soluble sugar increased 24.0% and 29.4% by compared with 50 μmol/L H₂S treatment alone at 50 μmol/L H₂S and 1.5 mmol/L H₂O₂ ,proline content increased by 25.8% and 21.3%,respectively,and the effect of salt stress alleviation was the most significant.In summary,there were a certain degree of synergy between exogenous H₂S and H₂O₂,which could enhance the osmotic regulatory capacity of plants under enhanced NaCl stress in tomato seedling plants to enhance the removal of reactive oxygen species H₂S and H₂O₂ in the tomato seedlings,and then weakened the injury of reactive oxygen species on the plasma membrane in processed tomato cells and then increased the adaptability of tomato seedlings to salt stress. The synergistic effect of the two signaling molecules will provide the theoretical basis for alleviating the physiological mechanism of salt stress in tomato seedlings.

Key words: H₂O₂, H₂S, NaCl stress, Processing tomato seedlings

中图分类号: 

• S641.01