Abstract:We sprayed different concentrations of salicylic acid (0.5, 1, 2, 4, 8 mmol·L-1) and 10 μmol·L-1 1aminophentriazole (ABT), which was the inhibitor of salicylic acid on the seedling leaves of S. rebaudiana in the greenhouses and in the field, in order to explore the effects of salicylic acid on the main agronomic traits, glucoside and salicylic acid contents of S. rebaudiana leaves during harvest period. The results showed that: (1) the main agronomic characters of S. rebaudiana in the greenhouse and field increased first and then decreased with the increase of salicylic acid concentration in this experiment. Under the treatment of 2 mmol·L-1 salicylic acid, the main agronomic characters of S. rebaudiana increased significantly in the greenhouse and field. And the dry weight per plant was 1.03 g and 16.76 g, respectively, which increased by 39.96% and 9.52% compared with 0.76 g and 12.34 g of the control. ABT treatment inhibited the agronomic traits of S. rebaudiana to some degree. (2) The contents of total glycoside and its composites of S. rebaudiana increased obviously under 1 mmol·L-1 salicylic acid treatment, and reached the highest under 2 mmol·L-1 salicylic acid treatment. The total glucoside contents of S. rebaudiana leaves in the greenhouse and field were 16.75% and 14.57%, respectively, which increased by 25.66% and 16.18% compared with 13.33% and 12.03% of the control, and RA glycosides also increased significantly to 10.59% and 9.77%, respectively. (3) The salicylic acid contents of S. rebaudiana leaves at the harvest time under 1 mmol·L-1 and 2 mmol·L-1 salicylic acid treatments had no significant difference with that of the control, but increased significantly after treatment with 4 and 8 mmol·L-1 salicylic acid. The salicylic acid contents decreased a little under the treatments with ABT. It is suggested that spraying appropriate concentration of salicylic acid help to improve the yield and glycoside content of S. rebaudiana, especially the RA content. 2 mmol·L-1 salicylic acid could be used to spray S. rebaudiana at the seedling stage in order to improve the yield and quality.