ABSTRACT
Cut flowers are commonly exposed to water stress, since they are subjected to periods of dry storage in marketing channels. This chapter discusses the chemical treatments that increase flower longevity by maintenance of water balance, inhibition of ethylene biosynthesis or action, and other modes of action. It provides information on postharvest physiology of cut flowers and horticultural practices involved in the flower industry. One of the present and future challenges in the field of postharvest physiology of flowers is to determine regulatory mechanisms of senescence in those flowers that are not very sensitive to ethylene, and that do not respond to inhibitors of ethylene biosynthesis or action. The plant hormones auxin and cytokinin appear to be involved in suppressing flower senescence, and abscisic acid in promoting it. A fact that should be kept in mind when investigating chemical compounds as floral preservatives is that the carbohydrate status of the flowers is important.
