Phytosulfokine α (PSKα) delays senescence in cut rose flowers by keeping intracellular ATP and ROS homeostasis

During bud opening of rose flowers, higher TOR along with lower SnRK1 expression was concomitant with sufficient cellular ATP provision, while during petal senescence of rose flowers, lower TOR along with higher SnRK1 expression was concomitant with insufficient cellular ATP supplying. During bud opening, higher TOR expression might ensure sufficient cellular ATP provision by promoting H+-ATPase, Ca2+-ATPase, SDH, and CCO activities. During petal senescence, higher SnRK1 expression might ensure for insufficient cellular ATP supplying which was associated with higher AOX, UCP1, ProDH and IVDH expression. By PSK alpha application, triggering TOR along with suppressing SnRK1 expression could be responsible for sufficient cellular ATP provision by promoting H+-ATPase, Ca2+-ATPase, SDH, and CCO activities accompanied by suppressing ProDH and IVDH expression. In addition, higher AOX and UCP1 expression might ensure lower H2O2 accumulation in cut rose flowers by PSK alpha application. By PSK alpha application, retarding senescence and extending vase life of cut rose flowers was associated with maintaining membrane integrity indicated by lower electrolyte leakage and MDA accumulation. Our results suggest the potential of TOR/SnRK1 signaling pathways as an effective endogenous anti-senescence molecular mechanism for extending the vase life of cut rose flowers.