Oxidative stress occurs when crop plants are exposed to extreme abiotic conditions that lead to the excessive production and accumulation of reactive oxygen species(ROS).Those extreme abiotic conditions or stresses in...Oxidative stress occurs when crop plants are exposed to extreme abiotic conditions that lead to the excessive production and accumulation of reactive oxygen species(ROS).Those extreme abiotic conditions or stresses include drought,high temperature,heavy metals,salinity,and ultraviolet radiation,and they cause yield and quality losses in crops.ROS are highly reactive species found in nature that can attack plant organelles,metabolites,and molecules by interrupting various metabolic pathways until cell death occurs.Plants have evolved defense mechanisms for the production of antioxidants to detoxify the ROS and to protect the plant against oxidative damage.Modern researches in crop plants revealed that low levels of ROS act as a signal which induces tolerance to environmental extremes by altering the expression of defensive genes.In this review,we summarized the processes involved in ROS production in response to several types of abiotic stress in cotton plants.Furthermore,we discussed the achievements in the understanding and improving oxidative stress tolerance in cotton in recent years.Researches related to plant oxidative stresses have shown excellent potential for the development of stress-tolerant crops.展开更多
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
文摘Oxidative stress occurs when crop plants are exposed to extreme abiotic conditions that lead to the excessive production and accumulation of reactive oxygen species(ROS).Those extreme abiotic conditions or stresses include drought,high temperature,heavy metals,salinity,and ultraviolet radiation,and they cause yield and quality losses in crops.ROS are highly reactive species found in nature that can attack plant organelles,metabolites,and molecules by interrupting various metabolic pathways until cell death occurs.Plants have evolved defense mechanisms for the production of antioxidants to detoxify the ROS and to protect the plant against oxidative damage.Modern researches in crop plants revealed that low levels of ROS act as a signal which induces tolerance to environmental extremes by altering the expression of defensive genes.In this review,we summarized the processes involved in ROS production in response to several types of abiotic stress in cotton plants.Furthermore,we discussed the achievements in the understanding and improving oxidative stress tolerance in cotton in recent years.Researches related to plant oxidative stresses have shown excellent potential for the development of stress-tolerant crops.
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.
