Endogenous hydrogen gas delays petal senescence and extends the vase life of lisianthus cut flowers

Exogenous hydrogen-rich water (HRW) improves vase life and quality of cut flowers, but the effects of endogenous hydrogen gas (H2) are not known. During the vase of cut lisianthus flowers, endogenous H2 concentrations decreased and redox homeostasis was impaired. The supplementation with HRW containing 0.078 mmol L−1 H2 blocked, but 2,6-dichlorophenolindophenol (DCPIP; a putative inhibitor of H2 synthesis) increased, endogenous H2 production. Senescence of cut flowers was delayed by H2, but accelerated by DCPIP. Also, decreased vase life by DCPIP was blocked by H2 administration. These beneficial roles of H2 were associated with less lipid peroxidation, and the increased activities of superoxide dismutase, ascorbate peroxidase, guaiacol peroxidase, and catalase. Compared with DCPIP alone, the soluble protein, total chlorophyll, and proline contents were elevated when H2 and DCPIP were added together. Overall, endogenous H2 prolongs vase life of lisianthus cut flowers in part by maintaining redox homeostasis.