This study assessed the influence of exogenous ME in the mitigation of cold damage in pepper seedlings. Melatonin(ME) is a dynamic molecule that helps plants cope with stress in several ways. Cold stress(CS) is one of...This study assessed the influence of exogenous ME in the mitigation of cold damage in pepper seedlings. Melatonin(ME) is a dynamic molecule that helps plants cope with stress in several ways. Cold stress(CS) is one of the most important environmental factors that restrict plant growth and yield. Pepper(Capsicum annuum L.) is a valuable commercial crop, highly sensitive to CS. Thus, identifying an efficient strategy to mitigate cold damage is critical for long-term pepper production. For this purpose, the roots of pepper seedlings were pretreated with ME(5 μmol · L^(-1)) and exposed to CS for 7 d. The results indicated that CS suppressed pepper growth, hampered photosynthetic capacity, and damaged root architecture in pepper plants. In contrast, the production of reactive oxygen species(ROS), malondialdehyde(MDA), electrolyte leakage(EL), proline, and soluble sugars were enhanced in plants under CS. ME(5 μmol · L^(-1)) pretreatment reduced the negative effects of CS by recovering plant growth, root traits, gas exchange elements, and pigment molecules compared to CS control treatment. Furthermore, ME application efficiently reduced oxidative stress markers [hydrogen peroxide(H_(2)O_(2)), superoxide ion(O_(2)^(·-)), EL, and MDA] while increasing proline and soluble sugar content in pepper leaves. ME application combined with CS further increased antioxidant enzymes and related gene expression. Collectively, our results confirmed the mitigating potential of ME supplementation for CS by maintaining pepper seedling growth,improving the photosynthesis apparatus, regulating pigments, and osmolyte content.展开更多
Salinity is one of the major constraints reducing plant growth and yield.Irrigation with poor quality and brackish water to orchards is a major cause of stunted growth and low yield.The salt tolerance mechanism is one...Salinity is one of the major constraints reducing plant growth and yield.Irrigation with poor quality and brackish water to orchards is a major cause of stunted growth and low yield.The salt tolerance mechanism is one of the complicated genomic characters that is very problematic to develop in fruit trees and becomes much more severe at any growth and developmental stage.Osmotic stress and hormonal imbalances are major constraints causing low biomass production.Fruit tree tolerance/sensitivity is chiefly based on the activation of a defense system comprised of super-oxidase dismutase(SOD),peroxidase(POD)and catalases(CAT),non-enzymatic compounds including ascorbic acid,phenolics,flavonoids,stress indicators[i.e.,hydrogen peroxide(H2O2),lipid peroxidation,malondialdehyde(MDA),reactive oxygen species(ROS)and osmolytes containing proline,glycine-betaine(GB),ascorbates(APX),glutathione peroxidase(GPX)and glutathione reductase(GR)].Tolerant genotypes must have higher antioxidant assays to cope with the adverse effects of salinity stress because their defense system had the potential to scavenge toxic ROS and protect from membrane leakage.Some work is conducted on agronomic and horticultural crops;however,underutilized fruit crops are still neglected and need serious consideration from plant researchers.Minor fruit crops especially Zizyphus had excellent nutritional aspects.The current study provides detailed insights into the physiological and biochemical mechanisms of Zizyphus species to cope with the adverse effects of salinity by improving their plant defense system.The development of salt-tolerant germplasm is a requisite and can be developed by utilization of physiological,biochemical,and molecular mechanisms.Application of different molecular approaches(i.e.,genome mapping,genome editing,genetic transformation,proteomics,transcriptomics,and metabolites)are effective for higher yield by improving tolerance mechanisms.展开更多
基金supported by the Major Science and Technology Plan of Hainan Province (Grant No.ZDKJ2021010),ChinaNational Key Research and Development Program,(Grant No.2018YFD1000800) Chinathe National Natural Science Foundation (Grant No.31660091),China。
文摘This study assessed the influence of exogenous ME in the mitigation of cold damage in pepper seedlings. Melatonin(ME) is a dynamic molecule that helps plants cope with stress in several ways. Cold stress(CS) is one of the most important environmental factors that restrict plant growth and yield. Pepper(Capsicum annuum L.) is a valuable commercial crop, highly sensitive to CS. Thus, identifying an efficient strategy to mitigate cold damage is critical for long-term pepper production. For this purpose, the roots of pepper seedlings were pretreated with ME(5 μmol · L^(-1)) and exposed to CS for 7 d. The results indicated that CS suppressed pepper growth, hampered photosynthetic capacity, and damaged root architecture in pepper plants. In contrast, the production of reactive oxygen species(ROS), malondialdehyde(MDA), electrolyte leakage(EL), proline, and soluble sugars were enhanced in plants under CS. ME(5 μmol · L^(-1)) pretreatment reduced the negative effects of CS by recovering plant growth, root traits, gas exchange elements, and pigment molecules compared to CS control treatment. Furthermore, ME application efficiently reduced oxidative stress markers [hydrogen peroxide(H_(2)O_(2)), superoxide ion(O_(2)^(·-)), EL, and MDA] while increasing proline and soluble sugar content in pepper leaves. ME application combined with CS further increased antioxidant enzymes and related gene expression. Collectively, our results confirmed the mitigating potential of ME supplementation for CS by maintaining pepper seedling growth,improving the photosynthesis apparatus, regulating pigments, and osmolyte content.
文摘Salinity is one of the major constraints reducing plant growth and yield.Irrigation with poor quality and brackish water to orchards is a major cause of stunted growth and low yield.The salt tolerance mechanism is one of the complicated genomic characters that is very problematic to develop in fruit trees and becomes much more severe at any growth and developmental stage.Osmotic stress and hormonal imbalances are major constraints causing low biomass production.Fruit tree tolerance/sensitivity is chiefly based on the activation of a defense system comprised of super-oxidase dismutase(SOD),peroxidase(POD)and catalases(CAT),non-enzymatic compounds including ascorbic acid,phenolics,flavonoids,stress indicators[i.e.,hydrogen peroxide(H2O2),lipid peroxidation,malondialdehyde(MDA),reactive oxygen species(ROS)and osmolytes containing proline,glycine-betaine(GB),ascorbates(APX),glutathione peroxidase(GPX)and glutathione reductase(GR)].Tolerant genotypes must have higher antioxidant assays to cope with the adverse effects of salinity stress because their defense system had the potential to scavenge toxic ROS and protect from membrane leakage.Some work is conducted on agronomic and horticultural crops;however,underutilized fruit crops are still neglected and need serious consideration from plant researchers.Minor fruit crops especially Zizyphus had excellent nutritional aspects.The current study provides detailed insights into the physiological and biochemical mechanisms of Zizyphus species to cope with the adverse effects of salinity by improving their plant defense system.The development of salt-tolerant germplasm is a requisite and can be developed by utilization of physiological,biochemical,and molecular mechanisms.Application of different molecular approaches(i.e.,genome mapping,genome editing,genetic transformation,proteomics,transcriptomics,and metabolites)are effective for higher yield by improving tolerance mechanisms.
