Changes of Bioactive Compounds and Ethylene Production of Japanese Plums Treated with Pre-Harvest Aminoethoxyvinylglycine

Abstract

The effects of pre-harvest aminoethoxyvinylglycine treatments on bioactive compounds, fruit ripening, and quality of plum fruits (Prunus salicina Lindell cvs. "Black Beauty," "Black Amber," and "Friar") were investigated in this research. Whole trees were sprayed once with an aqueous solution containing aminoethoxyvinylglycine (0, 100, and 200 mg L-1) two weeks before the anticipated commercial harvest for each cultivar separately. In all plum cultivars, the results showed that aminoethoxyvinylglycine treatments were effective in reducing ethylene production and respiration rate. The red color development was delayed by aminoethoxyvinylglycine treatments during the ripening. The fruit mass and geometric mean diameter significantly decreased, while loss of flesh firmness was decelerated with aminoethoxyvinylglycine concentrations. Aminoethoxyvinylglycine treatments decelerated loss of flesh firmness. Soluble solid content was reduced, whereas titratable acidity and ripening index increased with aminoethoxyvinylglycine treatments. Aminoethoxyvinylglycine-treated fruits exhibited lower levels of total phenolics, total antioxidant activity, and individual phenolics. This study revealed that pre-harvest aminoethoxyvinylglycine treatments were more effective in delaying plum fruit softening. The main advantage is to maintain the firmness of late-harvested fruit by retaining bioactive compounds of plum fruit.