Abstract: As one of the main devastating diseases, rice false smut has a direct effect on the yield and quality of rice. However, there are Lack of in-depth research on the effects and mechanism of rice false smut occurrence on the nutritional quality of rice grain. Liaogeng 433 (Oryza sativa. japonica) and Liaogeng 2501 (Oryza sativa. japonica), two high-quality rice varieties with moderately rice false smut susceptibility, were used as the mater ials for this study. Used non-targeted metabolomics analysis，there were 271 metabolites detected in rice grain, and the relative contents of 49 metabolites were affected by rice false smut. Among the metabolites, the relative contents of phenolic substances (Gallocatechin, 3-hydroxybenzoic acid, Chlorogenic acid and Sinapinic acid), polyamine substances (Spermine), vitamin substances (alpha-tocopherol and nicotinamide) and fatty acids (Dodecanoic acid and Palmitic acid) were significantly decreased, and the relative contents of intermediates of fatty acid biosynthesis (1-Monoolein, 2-Monoolein and 1-Monostearin), sugars (Kestose, Tagatose, Galactose, Inulotriose, Maltotiose and Trisaccharide), shikimic acid and α-ketoglutaric acid were significantly increased. Changes in these metabolites led to the following results: disorders in sugar metabolism, tricarboxylic acid cycle, fatty acid synthesis and secondary metabolism in rice, increased the chalkiness and the chalky gain percentage, and reduced the head rice percentage of rice, antioxidant capacity and nutritional quality of rice grain.

Key words: Rice false smut, non-targeted metabolomics, metabolites, nutritional quality, rice quality