外源硫化氢对盐胁迫下加工番茄幼苗生理生化特性的影响

为明确盐胁迫下外源硫化氢(H2S)对加工番茄幼苗的缓解作用,以耐盐性不同的2个加工番茄KT-7和KT-32为材料,采用盆栽法,研究了不同浓度(20,50,100,150μmol/L)的H2S供体硫氢化钠(Na HS)对250 mmol/L Na Cl胁迫下加工番茄幼苗生物量、叶片光合色素含量、相对含水量、根系活力、游离脯氨酸含量、抗氧化酶活性及膜质过氧化水平和丙二醛含量的影响。结果表明:低浓度的Na HS处理在一定程度上提高了盐胁迫下加工番茄幼苗的生物量、光合色素含量、相对含水量、根系活力、脯氨酸含量以及抗氧化物酶(SOD、POD、CAT)活性,而降低了电解质渗出率和丙二醛含量,其中以50μmol/L的Na HS处理效果最佳,与单独盐胁迫处理相比50μmol/L的Na HS使KT-7的生物量、叶绿素a、叶绿素b、类胡萝卜素含量、SOD活性分别增加30.8%~66.7%,61.8%,56.3%,57.0%,9.1%,而使电解质渗出率和丙二醛含量分别下降15.0个百分点和23.7%;使KT-32的生物量、叶绿素a、叶绿素b、类胡萝卜素含量、SOD活性,分别增加24.0%~96.4%,49.8%,52.0%,46.7%,10.2%,而使电解质渗出率和丙二醛含量分别下降12个百分点和24.2%。综上,外源H2S处理通过提高幼苗的抗氧化水平,减少盐胁迫对加工番茄幼苗造成的氧化损伤,在一定程度上提高了加工番茄幼苗对盐胁迫的适应能力。为进一步探索H2S缓解加工番茄盐胁迫的机理提供了理论依据。

Effect of Exogenous Hydrogen Sulfide on the Physiological and Biochemical Characteristics of Processing Tomato Seedlings under NaCl Stress

To investigate the alleviation effect of exogenous hydrogen sulfide on processing tomato seedling growth under salt stress,two processing tomato cultivars (KT-7 and KT-32) with different salt tolerances and treated with different concentrations (20,50,100,150 μmol/L) sodium hydrosulfide processing tomato seedling under 250 mmol/L NaCl stress.The low concentrations of sodium hydrosulfide were used to spray on the leaves of seedling,and to study the seedling biomass,photosynthetic pigment content,relative water content,root activity,free proline accumulation,autioxidant enzyme(SOD,POD,CAT) activities,electrolytic leakage and malondialdehyde (MDA) contents.According to the results,under the salt stress,exogenous H2S treatment significantly improved the processing tomato seedling biomass,photosynthetic pigment content,relative water content,root activity,proline content and autioxidant enzyme activities.However,electrolytic leakage and MDA contents had a significantly drop.Among them,50 μmol/L concentration had the best effect.Compared with salt stress alone,50 μmol/L NaHS increased seedling biomass,chloro phyll a content,chlorophyll b content,carotenoids content,SOD activities by 30.8％-66.7％,61.8％,56.3％,57.0％,9.1％,respectively,however,the electrolytic leakage and MDA contents descend 15 percentage points and 23.7％,in KT-7.50 mmol/L NaHS increased seedling biomass,chlorophyll a content,chlorophyll b content,carote noids content,SOD activities by 24.0％-96.4％,49.8％,52.0％,46.7％,10.2％,respectively,however,the electrolytic leakage and MDA contents descend 12 percentage points and 24.2％,in KT-32.These illustrated that the exogenous H2 S regulated the antioxidant levels in leaves to reduce oxidative damage on processing tomato seedling during salt stress that improved the processing tomato seedling adaptability to salt stress.This study provided the basis for the further study of H2S function on processing tomato salt stress response mechanism.