Symbiotic conserved arbuscular mycorrhiza fungi supports plant health.

Arbuscular mycorrhiza fungi (AMF) forms a multi-beneficial symbiotic relationship with the host plant, therefore it is considered to be an effective helper to promote plant health. However, failure to consider the source or universality of AMF is often unstable during application. Therefore, it is necessary to screen potential AMF inoculants based on the source and the relationship with host. In search of more effective and broad-spectrum AMF inoculants, we studied AMF community structure properties of healthy and diseased plants in 24 fields from four sampling sites. The results indicated that the environmental filtering effect of roots was obvious, which was manifested as a decrease of α-diversity from rhizosphere to root. Differences in α-diversity between healthy and diseased roots further indicate the importance of AMF communities within roots for maintaining plant health. Glomus is significantly enriched and dominant in healthy roots, independent of environment and phylogenically conserved. Spores were further isolated and evaluated for their disease-preventing and pro-growth properties. Based on whether they were symbiotic with plant and root-enrichment characteristics, isolated AMF spores were classified as symbiotic conserved, symbiotic non-conserved, and non-symbiotic AMF. After spores were propagated and inoculated to plant roots, only symbiotic conserved AMF significantly promoted plant growth and maintained health, highlighting the potential of symbiotic conserved AMF in sustainable plant production.