Vascular occlusion of cv. Patrizia gerbera flower stems

The present work had the objective to demonstrate, through scanning electron microscopy (SEM), vascular blockage related to the fast reduction of vase life and to evaluate the effectiveness of different floral preservative concentrations on the longevity of ‘Patrizia’ gerberas (Gerbera jamesonii). The treatments T1 – control (tap water), T2 – sterilized water and vials, T3 – 0.75%, T4 – 1.0% and T5 – 1.5% of the commercial floral preservative (Flower®) were applied in a completely randomized design with four replicates, each of five flowers with 50cm length stems. Vase life was not significantly extended as a result of the applied commercial floral preservative. All the tested concentrations resulted in significant reductions of colony-forming units (CFU) per mL of solution. Water uptake was higher along the first three days of vase life when the commercial product was added. SEM images show bacterial growth in the xylem of untreated gerbera stems, indicating that the addition of the floral preservative to the vase water is recommendable to control bacterial growth and to diminish the vascular blockage.