NEW STRATEGIES TO CONTROL CUT FLOWERS SENESCENCE EVOLUTION

A. PAULIN
Senescence of carnation comprises two phases; during the first phase, there was no measurable ethylene production and only a very slight efflux of electrolytes. The second phase was preceded by the ethylene outburst, and was characterized by a massive efflux of electrolytes leading rapidly to death. This ion leakage results from the cellular decompartmention that follows membrane deterioration. This deterioration involves peroxydation of the membrane lipids.

During ageing, and from the end of blooming, increases are noted in the activity of factors that initiate or promote lipid peroxidation (lipoxygenase, free radicals), while defense activities (essentially neutralization of free radicals) decrease. This suggests that loss of membrane integrity occurs from the start of wilting, because the peroxidation is initiated from the end of blooming.

An ethylene rise appeared when peroxidation began. Addition of exogenous ethylene resulted in concomitant onset of the ethylene burst and peroxidation.

Senescence can be slowed by retarding peroxidation, usually by neutralizing free radicals and by inhibition of lipoxygenase activity. Free radical scavengers such as 3, 4, 5 - trichlorophenol, inhibitors of Lox such as nordihydroguaïratic acid increase survival of carnations by 100 %. Inhibition of the ethylene burst (using silver salts) slows peroxidation and prolongs the life of cut flowers.

A new strategy for preservation is presented which is based on the use of these different inhibitors.

PAULIN, A. (1992). NEW STRATEGIES TO CONTROL CUT FLOWERS SENESCENCE EVOLUTION. Acta Hortic. 307, 189-202
DOI: 10.17660/ActaHortic.1992.307.24
https://doi.org/10.17660/ActaHortic.1992.307.24

Acta Horticulturae