Salt stress is a major abiotic stress limiting plant growth and yield. In the present study, the effects of exogenous H_(2)O_(2) on the reactive oxygen species(ROS) metabolism and the antioxidant system in leaves of N...Salt stress is a major abiotic stress limiting plant growth and yield. In the present study, the effects of exogenous H_(2)O_(2) on the reactive oxygen species(ROS) metabolism and the antioxidant system in leaves of Nitralia tangutorum Bobr. under salt stress were studied. N. tangutorum seedlings were subjected to 200 mmol·L^(-1) NaCl treatment with or without the exogenous application of H_(2)O_(2) for 7 days. The results showed that NaCl stress significantly increased the relative conductivity, the contents of thiobarbituric acid reactive substances(TBARS) and ROS(H_(2)O_(2) and O_(2)^(·-)), as well as promoted the activities of antioxidant enzymes including superoxide dismutase(SOD), peroxidase(POD), catalase(CAT), and ascorbate peroxidase(APX) in N. tangutorum leaves. In addition, exogenous H_(2)O_(2) decreased the relative conductivity, the contents of TBARS, H_(2)O_(2) and O_(2)^(·-), while further enhanced the activities of antioxidant enzymes. These results indicated that H_(2)O_(2) effectively alleviated the adverse effects of NaCl stress on N. tangutorum through the regulation of ROS metabolism.展开更多
Nitraria tangutorum Bobr.,a typical xero-halophyte,can be used for vegetation restoration and reconstruction in arid and semiarid regions affected by salinity.However,global climate change and unreasonable human activ...Nitraria tangutorum Bobr.,a typical xero-halophyte,can be used for vegetation restoration and reconstruction in arid and semiarid regions affected by salinity.However,global climate change and unreasonable human activity have exacerbated salinization in arid and semi-arid regions,which in turn has led to the growth inhibition of halophytes,including N.tangutorum.Arbuscular mycorrhizal fungi(AMF)and plant growth-promoting rhizobacteria(PGPR)have the potential to improve the salt tolerance of plants and their adaptation to saline soil environments.In this study,the effects of single and combined inoculations of AMF(Glomus mosseae)and PGPR(Bacillus amyloliquefaciens FZB42)on N.tangutorum were evaluated in severe saline soil conditions.The results indicate that AMF and PGPR alone may not adapt well to the real soil environment,and cannot ensure the effect of either growth promotion or salt-tolerance induction on N.tangutorum seedlings.However,the combination of AMF and PGPR significantly promoted mycorrhizal colonization,increased biomass accumulation,improved morphological development,enhanced photosynthetic performance,stomatal adjustment ability,and the exchange of water and gas.Co-inoculation also significantly counteracted the adverse effect of salinity on the soil structure of N.tangutorum seedlings.It is concluded that the effectiveness of microbial inoculation on the salt tolerance of N.tangutorum seedlings depends on the functional compatibility between plants and microorganisms as well as the specific combinations of AMF and PGPR.展开更多
基金Supported by the Natural Science Foundation of Heilongjiang Province(LH2019C021)。
文摘Salt stress is a major abiotic stress limiting plant growth and yield. In the present study, the effects of exogenous H_(2)O_(2) on the reactive oxygen species(ROS) metabolism and the antioxidant system in leaves of Nitralia tangutorum Bobr. under salt stress were studied. N. tangutorum seedlings were subjected to 200 mmol·L^(-1) NaCl treatment with or without the exogenous application of H_(2)O_(2) for 7 days. The results showed that NaCl stress significantly increased the relative conductivity, the contents of thiobarbituric acid reactive substances(TBARS) and ROS(H_(2)O_(2) and O_(2)^(·-)), as well as promoted the activities of antioxidant enzymes including superoxide dismutase(SOD), peroxidase(POD), catalase(CAT), and ascorbate peroxidase(APX) in N. tangutorum leaves. In addition, exogenous H_(2)O_(2) decreased the relative conductivity, the contents of TBARS, H_(2)O_(2) and O_(2)^(·-), while further enhanced the activities of antioxidant enzymes. These results indicated that H_(2)O_(2) effectively alleviated the adverse effects of NaCl stress on N. tangutorum through the regulation of ROS metabolism.
基金the National Key Research and Development Program of China(No.2017YFE0119100)the National Natural Science Foundation of China(No.42107513)the Key Research and Development Program of Gansu(No.21YF5FA151)。
文摘Nitraria tangutorum Bobr.,a typical xero-halophyte,can be used for vegetation restoration and reconstruction in arid and semiarid regions affected by salinity.However,global climate change and unreasonable human activity have exacerbated salinization in arid and semi-arid regions,which in turn has led to the growth inhibition of halophytes,including N.tangutorum.Arbuscular mycorrhizal fungi(AMF)and plant growth-promoting rhizobacteria(PGPR)have the potential to improve the salt tolerance of plants and their adaptation to saline soil environments.In this study,the effects of single and combined inoculations of AMF(Glomus mosseae)and PGPR(Bacillus amyloliquefaciens FZB42)on N.tangutorum were evaluated in severe saline soil conditions.The results indicate that AMF and PGPR alone may not adapt well to the real soil environment,and cannot ensure the effect of either growth promotion or salt-tolerance induction on N.tangutorum seedlings.However,the combination of AMF and PGPR significantly promoted mycorrhizal colonization,increased biomass accumulation,improved morphological development,enhanced photosynthetic performance,stomatal adjustment ability,and the exchange of water and gas.Co-inoculation also significantly counteracted the adverse effect of salinity on the soil structure of N.tangutorum seedlings.It is concluded that the effectiveness of microbial inoculation on the salt tolerance of N.tangutorum seedlings depends on the functional compatibility between plants and microorganisms as well as the specific combinations of AMF and PGPR.
