Improving vase life and keeping quality of cut rose flowers using a chlorine dioxide and sucrose holding solution

This study investigated the antimicrobial effect of chlorine dioxide (ClO₂) on the vase life of cut rose flowers (Rosa hybrida L. ‘Beast’), which were maintained in a standard holding solution containing 2% sugar. The cut flowers were treated with preservative solutions of tap water (TW,control), distilled water (DW), 2% sucrose, and 2% sucrose with 2 μL·L^-1 to 8 μL·L^-1 ClO₂. The addition of sucrose to DW caused early leaf chlorosis, and shortened the vase life of the flowers compared to TW or DW conditions, even though sucrose is a well-known carbohydrate source. The addition of 2 μL·L^-1 to 8 μL·L^-1 ClO₂ to the sucrose solution significantly extended flower vase life about four days more than TW or DW conditions, and about six days more than the sucrose solution. The relative fresh weight and water uptake of the cut flowers were dramatically decreased in the sucrose solution without ClO₂. Bacteria in the TW, DW, and sucrose holding solutions on day six were detected at counts of 2.3 × 10⁵ CFU/L, 4.8 × 10⁵ CFU/L, and 2.4 × 10⁶ CFU/L, respectively.However, bacteria were not detected in the holding solution that contained ClO₂. These results indicate an antimicrobial activity of ClO₂ that is useful for extending the postharvest life of cut rose flowers in a vase solution that contains sucrose.