Membrane lipid metabolism is involved in regulating γ-aminobutyric acid-mediated cold tolerance in peach fruit

Abstract

The cold-sensitive peach fruits are prone to chilling injury (CI). γ-aminobutyric acid (GABA) has been confirmed to effectively improve peaches’ cold tolerance. This research aimed to probe the role of dynamic changes in membrane lipid metabolism in GABA-mediated peaches’ cold tolerance and reveal the underlying mechanisms based on lipid metabolomics. GABA treatment improved peaches’ cold tolerance by reducing phosphatidic acid (PA) accumulation via inhibiting phospholipid degradation, attenuating PA biosynthesis, and maintaining higher phosphatidylcholine (PC) and phosphatidylethanolamine (PE) levels. Under chilling conditions, GABA treatment protected peaches against low-temperature stress and delayed CI by maintaining higher PC and PE levels and enhancing the massive accumulation of diacylglycerol (DAG) and triacylglycerol (TAG). This study provides a novel mechanism regulating cold tolerance of postharvest peach fruits.