Multi-omics of Pine Wood Nematode Pathogenicity Associated with Culturable Symbiotic Microbiota through an Artificial Assembly Approach

Pine wilt disease (PWD), caused by Pinewood nematode (PWN), is one of the most devastating forest diseases in the world. Bacteria and fungi existing in symbiosis with PWN are closely linked with the pathogenesis of PWD, but the relationship between PWN pathogenicity and the symbiotic microbiota is still ambiguous. This study explored the relationship between microbes and the pathogenicity of PWN by establishing a PWN-symbiotic microbe library, using this library to generate five artificial PWN-microbe symbiont (APMS) assemblies with aseptic PWN and inoculated with host pine tree. Further, multi-omics (metabolome, phenomics, and transcriptome) data were obtained from inoculated host pine tree, and their correlations with microbes (microbiome data) of different APMSs were built to narrow down the functional microbes (significant correlated with multi-omics data). Moreover, eight genera of functional microbes were reloaded onto aseptic PWNs and used to inoculate pine tree seedlings, to further explore the function of PWN-associated microbes. These results demonstrate a clear relationship between symbiotic microbes and the pathogenicity of PWN, and expand the knowledge on the interaction between PWD-induced forest decline and the PWN symbiotic microbiome.