低温诱导的桃果实采后膜脂代谢变化与冷害的关系

The Relationship Between Membrane Lipid Metabolism and Chilling Injury of Postharvest Peach Fruit Induced by Low Temperature

基于膜脂代谢组学研究低温诱导的桃果实采后膜脂代谢变化与冷害的关系。与4℃相比,8℃延缓了桃果实磷脂降解、磷脂酸(PA)生物合成以及脂肪酸去饱和酶基因表达水平的增加,进而降低PA积累和脂肪酸去饱和过程,保持高水平的磷脂酰胆碱(PC)、磷脂酰乙醇胺(PE)组分和脂肪酸不饱和度,最终延迟桃果实冷害发生。8℃诱导桃果实差异脂质代谢物数量显著增加,并在贮藏后期保持较高水平的甘油二酯(DAG)和较低水平的甘油三酯(TAG)组分,可能是8℃诱导的采后桃果实正常后熟软化过程和冷害作用的结果。综上所述,8℃下桃果实的膜脂代谢动态变化利于冷害的延迟。

Based on membrane lipid metabolomics,the study aimed to reveal the relationship between membrane lipid metabolism and chilling injury(CI)of postharvest peach fruit induced by low temperature.Compared with 4℃,8℃delayed the increase of the genes expression level of phospholipids degradation,phosphatidic acid(PA)biosynthesis and fatty acid desaturase in peach fruit,thereby reducing the process of PA accumulation and fatty acid desaturation,maintaining the high level of phosphatidylcholine(PC),phosphatidylethanolamine(PE)components and fatty acid unsaturation,ultimately delayed the occurrence of CI in peach fruit.In addition,8℃induced a significant increase in the number of differential lipid metabolites in peach fruit,and maintained a higher level of diglyceride(DAG)and a lower level of triglyceride(TAG)components in the late storage period,which might be the result of the normal post-ripening softening process and CI of postharvest peach fruit induced by 8℃.Taken together,the dynamic changes of membrane lipid metabolism induced by 8℃were beneficial to the delay of CI during postharvest peach fruit softening.