Abstract: In this study, the effects of Trichoderma erinaceum M6-5 volatile components on metabolites, respiration and energy metabolism of Alternaria alternata from postharvest Korla fragrant pear were investigated. Non-targeted metabolomics based on liquid chromatography-mass spectrometry (LC-MS) was used to determine the changes of metabolites in A. alternata after treatment with M6-5 volatile substances. At 0, 3, 5 and 7 days after fumigation with M6-5 volatile substances, the respiratory rate of A. alternata was measured, and the respiration inhibition rate were calculated. The levels of ATP, ADP, AMP and energy charge in the M6-5-treated and control groups as a function of culture time were determined by liquid chromatography (LC). The results showed that among the identified differential metabolites, 6-amyl-2h-pyrano-2-one (6pp), 4-ethylbenzaldehyde, 3,4-dimethylbenzoic acid, 4-phenylbutyric acid and 2-methoxyresorcinol were up-regulated, while 6-aminonicotinamide, 11-ketoacetyl cholesterol, 3-hydroxyconilone, jasmonic acid and benzoylsphenine were down-regulated by M6-5 volatile substances. Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis showed that the significantly differential pathway was involved in the biosynthesis of secondary metabolites. At the end of the 7 day incubation period, the respiration inhibition rate of A. alternata by M6-5 volatile substances was (49.64 ± 2.04)%. Compared with the control group, treatment with M6-5 volatile substances significantly reduced the levels of ATP, ADP, AMP and energy charge, indicating that it can keep the energy charge at lower levels, thereby resulting in imbalanced energy metabolism and inhibited respiratory rate and affecting metabolite changes.

Key words: non-targeted metabolomics; Trichoderma erinaceum; volatile substances; Alternaria alternata; inhibition