Effects Of NaHS On Root Ion Flow And Related Gene Expression In M Hupehensis Under NaCl Stress

In this test,M hupehensis seedlings were used as the test material.The H₂S donor sodium sulfide?NaHS?was used to pretreat the M hupehensis seedlings and then treated with 100mmol·L^-1 NaCl.Focus on the effects of lower and higher concentrations of H₂S pretreatment on antioxidant enzyme activity,oxidative damage,root ion content,flow rate,ion transporter activity and gene expression,cell death,and root morphology and configuration of H₂S.The effects of the antioxidant properties,ion movement,cell death and root growth of the lower fruit tree roots.The results show that:1.Low concentration of H₂S(0.1 mmol·L^-1 NaHS)increases the antioxidant enzyme activity of the roots,induces M hupehensis roots to enhance the antioxidant performance,maintains the root redox balance under salt stress,reduces electrolyte permeability and MDA content under NaCl treatment,and reduces Oxidative damage caused by salt stress,while high concentration of H₂S(1.0 mmol·L^-1 NaHS)decreased the antioxidant capacity of the root system and aggravated oxidative damage caused by ROS under salt stress.2.Low concentration of H₂S increases the H⁺-ATPase gene expression and enzyme activity in the plasma membrane of the root system,activates the SOS salt resistance pathway and regulates K⁺channel protein gene expression.By limiting Na⁺inflow and K⁺outflow under salt stress,it reduces Na⁺content and increases K⁺content.And low concentration of H₂S increased the content of H⁺and Ca²⁺in the root system,maintaining the balance of Na⁺/K⁺and ion homeostasis under salt stress,while high concentration of H₂S inhibited the expression of Na⁺and K⁺ion transporter genes and plasma membrane proton pump genes in the root system,causing Ion extravasation in the meristematic zone of the root system,and excessive Na⁺in the salt stress environment flows into the root system,destroying the root ion homeostasis.3.Low concentration H₂S maintains stable active oxygen and ion content in the root system under salt stress,reduces root cell mortality under NaCl treatment,inhibits root cell death caused by NaCl,and increases root fresh weight,root length,root surface area under salt stress,and it also weakened the inhibitory effect of NaCl stress on root growth;high concentration of H₂S destroys the redox balance and ion homeostasis of roots,promotes root cell death,and exacerbates the inhibition of root growth by NaCl.