摘要：Roses are widely used as cut flowers worldwide. Petal senescence confines the decorative quality of cut rose flowers, an impressively considerable economic loss. Herein, we investigated the SUMO1/SUMO E3 ligase SIZ1 signaling pathway during bud opening, and petal senescence of cut rose flowers. Our results exhibited that the higher expression of
SUMO1 and
SUMO E3 ligase SIZ1 during bud opening was accompanied by lower endogenous H
2O
2 accumulation arising from higher expression and activities of
SOD,
CAT,
APX, and
GR, promoting proline accumulation by increasing
P5CS expression and activity and enhancing GABA accumulation by increasing
GAD expression and activity. In harvested flowers, lower expressions of
SUMO1 and
SUMO E3 ligase SIZ1 during petal senescence were associated with higher endogenous H
2O
2 accumulation due to lower expression and activities of
SOD,
CAT,
APX, and
GR. Therefore, promoting the activity of the GABA shunt pathway as realized by higher expression and activities of
GABA-T and
SSADH accompanied by increasing
OAT expression and activity for sufficiently supply proline in rose flowers during petal senescence might serve as an endogenous antisenescence mechanism for slowing down petals senescence by avoiding endogenous H
2O
2 accumulation. Following phytosulfokine α (PSKα) application, postponing petal senescence in cut rose flowers could be ascribed to higher expression of
SUMO1 and
SUMO E3 ligase SIZ1 accompanied by higher expression and activities of
SOD,
CAT,
APX, and
GR, higher activity of GABA shunt pathway as realized by higher expression and activities of
GAD,
GABA-T, and
SSADH, higher expression and activities of
P5CS and
OAT for supplying proline and higher expression of
HSP70 and
HSP90. Therefore, our results highlight the potential of the PSKα as a promising antisenescence signaling peptide in the floriculture industry for postponing senescence and extending the vase life of cut rose flowers.
