Ethylene suppression modifies gene expression and activity of aroma volatile-related enzymes in 'Delbard Estivale' apples

Abstract

The aim of this study was to assess the effect of AVG- and 1-MCP treatment on the postharvest behaviour of ‘Delbarde Estivale’ apple kept at room temperature, with special emphasis on the biosynthesis of odor volatiles. Fruits were harvested at the proper time, and subjected to AVG (ReTain®) treatment 3 weeks before harvest date. Another lot of fruits were treated with 1-MCP. Both treatments had a negative impact on the biosynthesis of odour-volatiles, in particular on ester-type compounds. The activities of lipoxygenase (LOX), alcohol dehydrogenase (ADH), and pyruvate decarboxylase (PDC) were declined by these treatments, whereas the alcohol o-acyltransferase (AAT) activity was higher in 1-MCP treated fruit. Gene expression assessment confirmed these trends. Results confirm the important role of an adequate supply of substrates for the biosynthesis of volatile esters in apple fruit.