Exogenous application of polyamines influences fruit quality of 'Zaferani' peach

Polyamines are positively charged small aliphatic amines, ubiquitous in nature, and are involved in various physiological processes including flowering, fruit growth and development, and senescence. An experiment was therefore conducted to test whether the application of polyamines (putrescine and spermidine) at various concentrations (0, 0.1, 0.5, and 1.0 mM) one week after full bloom would improve fruit quality of peach. The results showed that fruit weight and pulp firmness were affected by the types and various concentrations of polyamines applied at harvest time. Among the two polyamines tested, putrescine was the most effective in increasing fruit weight and pulp firmness. All concentrations of polyamines increased fruit weight and pulp firmness compared with control treatment. However, according to the taste panel results, fruit treated with 0.1 mM putrescine had a better quality in terms of firmness, appearance and taste. Soluble solid content and titrable acidity of the fruit were not significantly affected by the use of polyamines.