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• Endophyte induced JA accumulation, promoted ET and Pip biosynthesis. • Jasmonic acid and ET positively regulated host's disease resistance. • Endophyte promoted phenolics accumulation in host via L-tyrosine metabolism pathway. • Endophyte might induced ISR in host via JA/ET signaling pathways. Epichloë endophytes can improve the resistance of host grasses to pathogenic fungi in grasslands. However, little is known about the mechanisms involved. We investigated the mechanisms underlying the effect of Epichloë sibirica on the resistance of Achnatherum sibiricum to Curvularia lunata by metabolomics approaches. The results demonstrated that before and after pathogen inoculation, 58 and 157 differential metabolites (DMs) were respectively induced by endophytes. Kyoto Encyclopedia of Genes and Genomes (KEGG) analyses of DMs showed that amino acids and phenols were mostly accumulated by endophytic infection. Moreover, integrated transcriptome and metabolomics KEGG analyses revealed that plant hormone signal transduction was significantly enriched. After measurement, we found that endophytic infection increased jasmonic acid (JA) concentration before pathogen inoculation and increased ethylene (ET) and pipecolic acid concentration after pathogen inoculation. Exogenous phytohormones treatment verified that endophytes improved the disease resistance of A. sibiricum by promoting JA and ET accumulation. In phenylpropanoid synthetic pathway, the endophytes promoted the accumulation of ferulic acid, p-coumaroylagmatine, and feruloylputrescine which was related to resistance against plant disease. Overall, our research suggests that Epichloë endophytes presumably trigger induced systemic resistance of the hosts to pathogenic fungi via activating JA/ET signaling pathways and promoted antimicrobial phenol accumulation in hosts. [ABSTRACT FROM AUTHOR]

• Formation mechanisms for PbS nanomaterials grown on silica substrate are studied by DFT. • PbS are doped into the fiber core via ALD, with nanostructure confirmed by HRTEM. • PbS-doped fiber exhibits fluorescence property at 1060–1370 nm with 1064 nm pumping. • PbS-doped fiber amplifier exhibited a signal gain as 9.4 dB at 1310 nm. The formation mechanisms for lead sulfide (PbS) semiconductor nanomaterials grown on silica substrate were investigated using density functional theory. There are two main reaction processes for the adsorption of Pb(tmhd) 2 on a silica substrate and the reaction with H 2 S to form PbS. The activation barriers of the two reaction processes were quite low at 10.1923 and 20.6778 kcal/mol, which is energetically favorable for PbS deposition by atomic layer deposition (ALD). In addition, PbS nanomaterials were introduced both on silica substrate and into the core of the silica fiber via ALD, with Pb(tmhd) 2 and H 2 S as precursors. The structural properties of the PbS nanomaterials and optical properties of the PbS-doped fiber were characterized. There were obvious absorption peaks at 480, 695, and 1043 nm. The fiber exhibited photoluminescence at 1060–1370 nm with 1064 nm pumping. A gain of 9.4 dB was obtained at 1310 nm, which can be attributed to the PbS nanomaterials in the fiber core. This is crucial for optical fiber communications. [ABSTRACT FROM AUTHOR]