The starch, lipid, cytochrome oxidase (EC 1.9.3.1), succinic dehydrogenase (EC 1.3.99.1), peroxidase (EC 1.11.1.7), and acid phosphatase (EC 3.1.3.2) levels were determined periodically by histochemical methods in transverse sections of cut stem of the rose,Rosa hybridaL. cv. Forever Yours, kept in water or in an aqueous preservative solution containing 4 sucrose, 100ensp;ppm sodium isoascorbate, and 100ensp;ppm 8-hydroxyquinoline sulfate. Senescence of the cutrose stem, including leaves and flowers, was delayed by use of the sugar solution. The levels of cytochrome oxidase and succinic dehydrogenase were not significantly affected by either of the treatments. Starch, lipid, peroxidase, and acid phosphatase levels decreased in the tissues of rapidly senescing stems kept in water. In tissues where senescence was retarded by use of sugar solutions the lipid content and peroxidase were maintained at a relatively high level; starch, and acid phosphatase levels steadily increased. It is suggested that in cut rose stems, the onset or retardation of senescence is not related to the activities of acid phosphatase or peroxidase.
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