Interspecific interactions including plant–plant, plant–microbe, and plant–insect are the important elements to drive the positive plant–soil feedback for maintaining ecosystem stability in biodiversity ecosystems. Yet, the role of diversified foliar pathogens in biodiversity system in influencing the plant–soil feedback (PSF) has often been underestimated. Here, we assessed the effects of foliar Alternaria panax pathogenicity diversity from agroforestry system on PSF and rhizosphere microbial community. We show that a moderate intensity of foliar pathogen infection by A. panax could activate jasmonic acid (JA)-mediated defense from shoots to roots. This activation enhanced the synthesis and secretion of 2-aminoethanesulfonic acid into the rhizosphere for a disease-suppressive rhizo-microbiota assembly, contributing to positive PSF. However, excessive foliar pathogen infection allocated JA-mediated defense only in leaf and disrupted this rhizomicrobial enrichment, resulting negative PSF. This study enhances the understanding of the ecological roles of foliar pathogen within agroforestry systems and provides an insight into agricultural sustainability.

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