Abstract: The effect of SA on physiological indexes and gene expression were studied in tomato seedlings under low potassium stress in order to provide an important theoretical basis for the relationship between SA and low potassium stress. In this study,the different concentrations of salicylic acid (SA) (0.10,0.25,0.50,1.00 mmol/L) affect antioxidant enzyme activities and gene expression in tomato seedlings under low-potassium stress were investigated.The results showed that the chlorophyll (Chl) and proline (Pro) contents,as well as catalase (CAT),ascorbate peroxidase (APX),peroxidase (POD) and superoxide dismutase (SOD) activities,were significantly increased,and malondialdehyde (MDA) concentration decreased under 0.25 mmol/L SA treatment compared with that in the control.Meanwhile,the gene expression levels of APX,CAT,POD,and SOD in tomato leaves were analyzed through quantitative Real-time PCR.Four gene expression levels of antioxidant enzymes were considerably increased after 48,96 h treatment.These results suggested that SA promoted the gene expression levels of APX,CAT,POD,and SOD to alleviate the damage of low potassium stress,and decreased the accumulation of ROS and enhanced resistance in tomato seedlings under low-potassium stress.

Key words: Salicylic acid, Tomato, Potassium, Antioxidant enzyme, Gene

CLC Number: 

• Q78