title: Peach (Prunus persica) fruit ripening: aminoethoxyvinylglycine (AVG) and exogenous polyamines affect ethylene emission and flesh firmness.
abstract: The effect of various concentrations of aminoethoxyvinylglycine (AVG; 0.32 and 1.28 mM), an ethylene biosynthesis inhibitor, and of the polyamines putrescine (10 mM), spermidine (0.1, 1 and 5 mM) and spermine (2 mM) on peach (Prunus persica L. Batsch cv. Redhaven) fruit ripening was evaluated under field conditions. Treatments were performed 19 (polyamines) and 8 (AVG) days before harvest. Fruit growth (diameter, fresh and dry weight), flesh firmness, soluble solids content and ethylene emission were determined on treated and untreated (controls) fruits. Moreover, endogenous polyamine content and S-adenosylmethionine decarboxylase (SAMDC, EC 4.1.1.21) activity were determined to check for a possible competition between polyamines and ethylene for their common precursor S-adenosylmethionine (SAM). Both treatments strongly inhibited ethylene emission and delayed flesh softening. On a biochemical level, AVG and exogenous polyamines both reduced the free-to-conjugate ratio of endogenous polyamines, and transiently altered SAMDC activity. The possible use of these compounds to control fruit ripening is discussed also in the light of their rejuvenating effect on peach fruits.
authors.affiliation: Dipartimento di Colture Arboree, University of Bologna, Via Filippo Re 6, I-40126 Bologna, Italy Dipartimento di Biologia e.s., Università di Bologna, Via Irnerio 42, I-40126 Bologna, Italy.
authors.forename: Anna M
authors.initials: AM
authors.lastname: Bregoli
authors.forename: Sonia
authors.initials: S
authors.lastname: Scaramagli
authors.forename: Guglielmo
authors.initials: G
authors.lastname: Costa
authors.forename: Emidio
authors.initials: E
authors.lastname: Sabatini
authors.forename: Vanina
authors.initials: V
authors.lastname: Ziosi
authors.forename: Stefania
authors.initials: S
authors.lastname: Biondi
authors.forename: Patrizia
authors.initials: P
authors.lastname: Torrigiani