Postharvest treatments to optimize long-term storage of cut peony flowers

Cut peonies have limited time during which they can be harvested and commercialized. Interest in extending this period through long-term storage, both in dry and wet conditions, to obtain more profits is constantly growing. Sixty cut peony stems (cv. Alertie) were pulse-treated 24 h after har- vest with 10 μM thidiazuron, 500 μL L-1 1-methylcyclopropene, 10 mM glycerol, and a combination of them (All) in a refrigerated cell at 4 °C, where the flowers were stored with wet preservation for 15 and 30 days. After these periods, flowers were maintained at 20 °C, and their quality was assessed through in vivo and destructive analyses at 0, 4, 12, and 14 days. Thirty days of storage strongly inhibited flower opening, in contrast to the shorter preservation period. After 15 days of storage and during preservation at room temperature, flowers treated with glycerol showed less water loss and senescence symptoms. Nitrate and phenol concentrations increased in all treatments after storage. In conclusion, wet storage at 4 °C for 15 days was more suitable for the cultivar tested in the present study and it also allowed the identification of treatments that involved the use of glycerol as promising for long-term preservation of peonies and their vase-life.