Analysis of volatile compounds and metabolic mechanisms of stony hard peach after ethylene treatment

Stony hard peaches (Prunus persica L. Batsch) are a type of fruit with a relatively mild flavor. Ethylene treatment can increase its aroma compounds and improve the flavor of stony hard peaches. However, the effect of ethylene treatment on the metabolic processes and mechanisms of volatile compounds in stony hard peaches remain unclear. In this study, the composition and contents of volatile compounds, and differentially accumulated volatile compounds in three cultivars of stony hard peaches treated ethylene were analyzed by gas chromatography–mass spectrometry. Furthermore, transcriptome analysis was performed to identify differentially expressed genes and potential genes involved in the metabolism of differentially accumulated volatile compounds, and to elucidate associated mechanisms. Four key differentially accumulated volatile compounds were identified in three typical stony hard peach cultivars treated with ethylene. Moreover, the differentially accumulated volatile compounds were mainly associated with fatty acid metabolism and isoflavonoid biosynthesis. Three genes associated with fatty acid metabolism were considered potential key genes regulating the accumulation of volatile compounds in stony hard peaches after ethylene treatment. This study provides novel insights into the effect of ethylene treatment on aroma formation in stony hard peaches and offers a theoretical basis for improving the quality of stony hard peaches.