Effect of Salicylic Acid on Antioxidant Enzyme Activity and Petal Senescence in ‘yellow Island’ Cut Rose Flowers

The effect of exogenous salicylic acid (SA) on the vase life of cut rose flowers was investigated. ‘Yellow Island’ roses were obtained from a commercial grower. The roses were pulse treated with SA (0, 50, 100, 150, 200 mg l) for 18 hours. Compared to the control treatment (DW), the greatest delay in senescence was obtained in cut roses treated with 150 mg l SA. With this treatment, flower vase life was doubled. The physiological characteristics such as protein concentration, lipid peroxidation (MDA) level and enzyme activity such as lipoxygenase (LOX), superoxide dismutase (SOD) and peroxidase (POD) were measured only in the control (DW) and those kept in a solution of 150 mg l salicylic acid (SA) for over 8 days of vase life. Degradation of protein and accumulation of MDA during vase life was shown to be suppressed by 150 mg l SA. The activity of LOX and POD gradually increased with progressing flower senescence, while SOD activity declined. The flowers which had been pulsed with SA exhibited lower LOX and POD activity, and a higher activity of SOD. Overall, the results suggest that SA increases vase life by improving the antioxidant system and reducing oxidative stress damages during rose flower senescence.