M. S. Reid
Many researchers have studied the physiology and biochemistry of ethylene action in senescence of some popular model flowers, such as carnation, and morning glory, whose demise is coordinated by a rise in the production of this plant hormone. In other commercially important flowers, ethylene plays a variety of roles. In roses, ethylene treatment may accelerate senescence or prevent opening, although it is not involved in natural senescence. In foxglove, ethylene accelerates corolla abscission; in cyclamen, this acceleration is contingent on prior pollination. Ethylene appears to play no important role in senescence of Composite inflorescences (chrysanthemum, gerbera) and of flowers of many monocotyledonous geophytes (daffodil, iris). The role of ethylene in the induction of flower senescence, and the means by which senescence is triggered in ethylene insensitive flowers is discussed.

Senescence can be broadly defined as those events leading to death of cells, tissues, or organs. Such a definition, applied to cut flowers, might include adverse water relations and floret abscission. Although ethylene probably plays a role in these processes, this review will consider only the stricter sense of senescence, the actual events occurring during aging and death of floral tissues.

Ethylene, a simple hydrocarbon gas, is an important natural regulator of many phases of plant growth and development (reviewed in Reid, 1987). One of the earliest known responses of plants to ethylene was the observation of "sleepiness" of carnation flowers in greenhouses contaminated with ethylene from faulty heaters or leaky gas pipes. At first, ethylene was considered to be a plant growth regulator only; its hormonal role was not established until the development of analytical methods sufficiently sensitive to measure the minute quantities produced by plant tissues. Studies over the past 20 years have provided considerable information on the role of ethylene in flower senescence. This review will briefly summarize these contributions.

Reid, M. S. (1989). THE ROLE OF ETHYLENE IN FLOWER SENESCENCE. Acta Hortic. 261, 157-170
DOI: 10.17660/ActaHortic.1989.261.20

Acta Horticulturae