Ethanol can increase the vase life of some cut flowers by inhibition of ethylene biosynthesis or ethylene action or both. The effect of different concentrations of ethanol (2, 4 and 6%) on carnation cultivars ‘Pilar’ and ‘Mundo’ was studied. Ethylene production, vase life, fresh weight and solution uptake were determined over time. Distilled water and silver thiosulphate (0.5 and 1 mM) were used for the control treatments. Continuous treatment with 2% ethanol increased vase life in both cultivars compared with the water treatment. In the senescence phase of ethanol-treated carnation flowers, the typical petal inrolling, characteristic of this process, was not observed, but stems were more dry and fragile, and stem diameter was reduced. The three concentrations of ethanol reduced the peak of ethylene production. The treatments with 2% ethanol delayed the ethylene production in both cultivars compared with the water treatment. All ethanol treatments resulted in less increase of fresh weight during the first days and greater relative fresh weight loss compare to the silver thiosulphate treatments, which could be related to a reduction of solution uptake.
