Penicillium-mediated toxicity and microbial dysbiosis are associated with fruiting body abortion in artificially cultivated Chinese cordyceps.

Chinese cordyceps consists of fruiting body and sclerotia (larvae part) formed through the parasitism of the insect Hepialidae by the fungus Ophiocordyceps sinensis, but artificial cultivation is hindered by fruiting body abortion, severely impacting yield and quality. The interactions between the fungus, its host insects, and soil are critical for its development. Multi-omics analyses were conducted to compare normally and abnormally developing samples, examining microbial communities and metabolites in fungus-colonized host larvae and the mycosphere soil. Abnormal fruiting body development was associated with profound shifts in microbial ecology: fungal diversity increased significantly in both endophytic larvae and mycosphere soil, whereas bacterial diversity decreased within host larvae. The microbial composition in and around abnormal samples was markedly altered, characterized by a high enrichment of Penicillium fungi and a depletion of Bacillus bacteria. Cross-kingdom microbial network analysis showed fewer connections and lower stability in abnormally developing samples. Untargeted metabolomic profiling revealed significant accumulation of the antibiotics N1-hydroxy-roquefortine C and glandicoline A, both roquefortine C derivatives characteristic of Penicillium metabolism, along with enriched pathways involved in antibiotic biosynthesis. Exploratory Partial Least Squares Structural Equation Modeling (PLS-SEM) analysis supported an associative pathway in which Penicillium-mediated toxicity is correlated with microbial dysbiosis, which in turn is associated with fruiting body abortion. Conversely, Bacillus may play a critical role in suppressing Penicillium overgrowth and maintaining microbial homeostasis, representing a promising target for biocontrol strategies. This study is the first to reveal potential links between Penicillium‑mediated toxicity, microbial imbalance, and developmental disorders of Chinese cordyceps.