Effects of continuous treatment with sucrose on the vase life, soluble carbohydrate concentrations, and ethylene production of cut snapdragon flowers

Effects of continuous treatment with sucrose on floret opening, vase life, carbohydrate concentrations, and ethylene production in cut snapdragon (Ant irrhinum majus L. cv. Yellow Butterfly) flowers were investigated. Continuo us treatment with sucrose at 25, 50, 75, or 100 g liter(-1) in combination with 200 mg.liter(-1) 8-hydroxyquinoline sulfate markedly promoted floret o pening and extended the vase life of flower spikes. The most effective sucr ose concentration was 50 g.liter(-1) so that this concentration was used fo r the following experiments. This treatment suppressed the decrease in fles h weight of florets. Glucose, fructose, sucrose, and mannitol were detected in petals. Glucose, fructose, and sucrose concentrations of petals in cont rol spikes decreased one day after the harvest and remained at low levels b ut the sucrose treatment suppressed the decrease in these sugars. Regardles s of the sucrose treatment, mannitol concentration gradually decreased. The onset of climacteric ethylene production was delayed by the sucrose treatm ent which suggests that the effects of sucrose for promoting bud opening an d inhibiting flower senescence is attributed to an increase in sugar concen trations and the inhibition of ethylene synthesis.