Abstract: Cut roses（Rosa hybrida‘Tineke’）were used to investigate the effects of abscisic acid （ABA）and nitric oxide（NO）on cut flower senescence and the interaction between NO and ABA during postharvest freshness. The results show that 0.5 μmol · L-1 ABA significantly increased the vase life and flower diameter compared with distilled water（the control）. However，1.0 and 2.0 μmol · L-1 ABA significantly reduced flower diameter in comparison with the control. 150 μmol · L-1 NO donor SNP increased vase life by 70.7% compared with the control. NO synthesis inhibitor sodium tungstate significantly inhibited the promotive effects of ABA on vase life and flower diameter，showing that NO was required for ABA-regulated senescence of cut roses. Moreover，ABA kept the relative water content of cut rose leaves，while sodium tungstate inhibited the positive effects of ABA. Furthermore，ABA significantly increased the activities of superoxide dismutase，peroxidase and ascorbate peroxidase in cut rose leaves. However，the promotive effect of ABA on the activities of antioxidant enzymes was reversed by sodium tungstate，indicating that NO is involved in ABA-induced antioxidant capacity during postharvest freshness. Together，our results show that NO might be involved in ABA-delayed senescence of cut flowers by maintaining water content and increasing activities of antioxidant enzymes.

Key words: rose, cut roses, nitric oxide, abscisic acid, water content, antioxidant enzyme