Comparison and analysis of widely targeted metabolomics of mycorrhizal of Lactarius akahatsu and Pinus massoniana

This study aims to analyze and compare the differences in root metabolites before and after mycorrhizal synthesis between Lactarius akahatsu and Pinus massoniana, in order to provide reference for exploring the potential substances regulating the symbiosis between L. akahatsu and P. massoniana.

The mycorrhizal of L. akahatsu and P. massoniana were synthesized on pure media. Liquid chromatography-mass spectrometry were used to determine the metabolic components of root system of P. massoniana and mycorrhizal of symbiotic system between L. akahatsu and P. massoniana. The metabolites were quantified and annotated using KEGG and HMDB databases. Principal component analysis, orthogonal partial least-squares discriminant analysis and other multivariate statistical methods were used to compare the metabolome data and screen the different metabolic components.

627 metabolites were detected from mycorrhizal between L. akahatsu and P. massoniana, of them 95 ones were differential metabolites, 39 ones were up-regulated and 56 were down-regulated. The main metabolites were flavonoids, terpenoids, amino acid and derivatives, phenols, alkaloids, organic acids and derivatives, nucleotide and its derivates, phenylpropanoids and lignan, phytohormone, etc. KEEG metabolic pathway analyses showed that different metabolites were significantly enriched in 9 metabolic pathways. They were biosynthesis of secondary metabolites, biosynthesis of phenylpropanoids, flavonoid biosynthesis, neuroactive ligand-receptor interaction, biosynthesis of siderophore group nonribosomal peptides, benzoate degradation, biosynthesis of plant hormones, biosynthesis of alkaloids derived from shikimate pathway and aminobenzoate degradation, which might be an important regulatory role in the formation of mycorrhizal synthesis between L. akahatsu and P. massoniana.

Using UPLC-MS/MS metabolomics technique, the metabolomics differences of mycorrhizal synthesis between L. akahatsu and P. massoniana can be revealed on an overall level. The results can provide a scientific basis for clarifying the symbiotic mechanism and the mycorrhizal synthesis of L. akahatsu and P. massoniana.