Physiological Regulation Effects Of Different NO₃^-Supply And Rhizobium Inoculation On Glycine Max And Glycine Soja Seedlings Under Salt Stress

In this study,Glycine max Lee68(the salt tolerant cultivar)and Jackson(the salt sensitive cultivar),and Glycine soja BB52(the salt tolerant population)and N23227(the salt sensitive population)populations were used as the experimental materials.By measuring the contents of Cl-NO3-?Na+?K+ and other indexes,the physiological mechanisms of alleviating the salt stress by improving the NO3-levels in vitro of plant and rhizobium inoculation on soybean seedlings were investigated.The results showed as follows:When the NO3-levels were improved in vitro of Glycine max Lee68 and Jackson under salt stress,the NO3-contents in vivo of two soybean seedlings can be increased,reducing Na+/K+ ratio and Cl-/NO3 ratio in leaves of two materials,inhibiting the increase of MDA contents and relative electrolytic leakage in roots and leaves,the root activity of two soybean seedlings were increased;in addition,correlation analysis founding that the root activity of Lee68 and Jackson and Cl-/NO3-ratio and Na+/K+ in roots was significantly negative,MDA contents and relative electrolytic leakage in roots and leaves and Cl-/NO3-and Na+/K+ were significantly positive.The contents of NO3-in roots of Lee68 and Jackson and K+ contents in leaves of Lee68 can be increased significantly by rhizobium inoculation on soybean seedlings of Glycine max Lee68 and Jackson under salt stress,reducing Na+ contents in stems both of two materials and Cl-contents,Na+ contents,Na+/K+ ratio and Cl-/NO3-ratio in leaves of Lee68,so the ameliorating effects is more obvious in Lee68 than Jackson.When the NO3-levels were improved in vitro of Glycine soja BB52 and N23227 under salt stress,the contents of NO3-in both of two materials and K+ contents in BB52 can be increased,reducing Na+ contents and Cl-contents and Na+/K+ ratio and Cl-/NO3-ratio in roots,stems and leaves both of two soybean materials,inhibiting the increase of relative electrolyte leakage in roots and leaves,restored growth of two soybean material;in addition,correlation analysis founding that the relative electrolytic leakage in roots and leaves of Glycine soja BB52 and N23227 population and Cl-/NO3-ratio and Na+/K+ ratio was significantly positive,plant height and fresh weight of Glycine soja BB52 and N23227 population and Cl-/NO3-ratio and Na+/K+ ratio in roots were significantly negative.The contents of NO3-in vivo of Glycine soja BB52 and N23227 can be increased by rhizobium inoculation under salt stress,reducing Cl-contents and Na+ contents in roots and stems of two materials,and the Na+/K+ ratio and Cl-/NO3-ratio were decreased in both of two materials,the contents of chlorophyll and root activity were increased in both of two materials,and the ameliorating effects on Cl-contents and Cl-/NO3-ratio is more obvious in leaves of BB52.Above all,the Cl-/NO3-and Na+/K+ ratio can be reduced in varying degrees in vivo of four kinds of soybean materials which have different salt tolerance by improving the NO3-levels in vitro of plant and rhizobium inoculation on soybean seedlings,alleviating the damage of salt stress on the soybean seedlings.