Effects of salt stress on the metabolism of active oxygen in seedlings of annual halophyte Glycine soja

In contrast with the annual Glycine max(Lee68,the salttolerant) and Glycine soja (N23232,the saltsensitive),the changes in producing rate of O-·2,contents of MDA,ascorbic acid(AsA),carotenoid(Car) and glutathione(GSH),the activities of superoxide dismutase (SOD),catalase(CAT),peroxidase(POD) and ascorbic acid peroxidase(APX)in halophyte BB52 (Glycine soja) seedlings were investigated under 150 and 300 mmol·L-1 NaCl stresses for 2 d.The results showed that,the producing rate of O-·2 in roots and leaves of BB52 seedlings all decreased,the SOD and the leaf APX activities all increased,as compared to the control plants.Under different concentrations of NaCl,the MDA content in roots showed no obvious ascent,and that in leaves increased slightly.The contents of AsA,Car and GSH in leaf of BB52,N23232 and Lee68 seedlings were all increased,and the increases in BB52 were higher.