Integrated analysis of lipid metabolism and differentially expressed genes reveal seed oil accumulation in field muskmelon

Field muskmelon (Cucumis melo L. var. agrestis Naud.), a novel oil crop, contains a high amount of lipids in seeds. However, the high-resolution profiles and dynamic regulation of its lipids remain largely unknown. This study identified the lipids and analyzed their dynamic changes using UHPLC-MS/MS. We identified 2533 lipid molecules in the seeds, including 7 categories and 47 sub-classes, with the higher proportions of glycerolipids (41.02 %) and glycerophospholipids (28.11 %). Moreover, the content of glycerolipids was the highest, particularly for triacylglycerol lipid molecules. Additionally, the expression patterns of differentially expressed genes (DEGs) showed a close correlation with lipid accumulation, especially within the plant hormone signaling pathway. Notably, the sufficient supply of 18:1-CoA, coupled with a high expression level of CmFAD2, contributed significantly to the high linoleic acid (68.56 %) content in field muskmelon seeds. Our findings offer insights that could enhance the comprehensive understanding of lipids in field muskmelon, and facilitate the breeding of field muskmelon.