H2S对Cd胁迫下大麦幼苗逆境生理及光合作用的影响  

Effects of Hydrogen Sulfide on Physiology and Photosynthesis of Barley Seedlings under Cd-stress

作　　者：李晓科[1] 武玉珍[1] 张谨华[1] 张义贤[2] LI Xiaoke;WU Yuzhen;ZHANG Jinhua;ZHANG Yixian(School of Biology Science and Technology,Jinzhong College,Jinzhong,Shanxi 030619,China;School of Life Science,Shanxi University,Taiyuan,Shanxi 030006,China)

机构地区：[1]晋中学院生物科学与技术学院,山西晋中030619 [2]山西大学生命科学学院,山西太原030006

出　　处：《福建农业学报》2020年第10期1131-1137,共7页Fujian Journal of Agricultural Sciences

基　　金：山西省自然科学基金项目(201701D121083);晋中学院2015年博士基金项目(2015006)。

摘　　要：【目的】为揭示H2S对Cd胁迫下大麦幼苗生长的胁迫效应规律,探讨H2S提高大麦幼苗耐镉的作用机制,并为大麦种植区镉污染防治提供一定的科学依据。【方法】采用室内水培法,以晋科571大麦品种为研究对象,设置以CdCl2(0.2 mmol·L^-1,处理中简称Cd)、外源H2S供体NaHS(50.0μmol·L^-1,处理中简称NaHS)和H2S生成抑制剂羟胺HA(1.0 mmol·L^-1,处理中简称HA)形成的不同处理组:Cd、NaHS、HA、Cd+NaHS、Cd+HA。测定不同处理组对大麦幼苗生长、叶片损伤、渗透调节物质、抗氧化酶活性、叶绿素含量及光合特性的影响。【结果】与Cd组相比,外源H2S缓解了Cd对幼苗生长的抑制和对叶片的损伤,表现为大麦幼苗根长、苗长、生物量增加,叶片相对电导率、丙二醛(MDA)及超氧阴离子(O2-)含量降低;促进了光合作用,表现为叶绿素含量和净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)增加;提高了大麦幼苗抵抗外界不良环境的能力,表现为渗透调节物质(可溶性糖、脯氨酸、可溶性蛋白)含量和抗氧化酶(SOD、POD、CAT)活性增加。【结论】在外源H2S供体NaHS溶液浓度为50.0μmol·L^-1时,Cd胁迫对大麦幼苗造成的伤害得到了一定程度的缓解,外源H2S能够增强大麦在Cd污染逆境中的适应能力。【Objective】 Rule of H2 S played on the growth of barley seedlings under Cd-stress was investigated to understand the mechanism and means to improve Cd-tolerance of the plants.【Method】 Treatment groups of Cd, NaHS, HA, Cd+NaHS,and Cd+HA with addition of CdCl2 at 0.2 mmol·L^-1, exogenous H2S donor NaHS at 50 μmol·L^-1 or H2 S synthesis inhibitor hydroxylamine HA at 1 mmol·L^-1 in medium were made for an indoor hydroponic barley seedling growth experiment. Effects of the treatments on the growth, leaf damage, osmotic regulator, antioxidant enzyme activity, chlorophyll content, and photosynthetic characteristics of the seedlings of Jinke 571 barley were monitored.【 Result】 The H2S addition in the hydroponic medium lessened the growth inhibition and leaf damage on the seedlings induced by Cd-stress. It increased the root length, plant height, and seedling biomass;decreased the leaf relative conductivity, malondialdehyde(MDA) and superoxide anion(O2-) contents;enhanced the photosynthesis with increased chlorophyll content, net photosynthetic rate, stomatal conductance, and transpiration rate;and, improved the resistance to the external adversity imposed on them with increased osmotic regulatory substances(e.g., soluble sugar, proline, soluble protein) and antioxidant enzymatic activities on SOD, POD,CAT.【Conclusion】 Addition of H2 S donor NaHS at 50 μmol·L^-1 in hydroponic medium partially alleviated the ill-effects of Cd-stress on the barley seedlings suggesting its potential field application for barley farming to combat the pollution.

关 键 词：CD胁迫 外源H2S 大麦 生理指标 

分 类 号：X171.5[环境科学与工程—环境科学]