Peat promotes production of the edible mushroom Oudemansiella raphanipes by regulating casing soil microbiome

Introduction As an exotic edible mushroom, Oudemansiella raphanipes has attracted extensive attention for efficient cultivation. Peat-amended casing soil is known to increase its productivity, while the underlying mechanisms remain unclear. Methods In this study, high-throughput 16S rRNA gene sequencing was performed to characterize bacterial communities in casing soils with five peat proportions. Results Results showed that peat proportion had a significant effect on O. raphanipes yield, with the 70% peat treatment achieving the maximum yield of 279.21 g per cultivation bag, 38.12% higher than the control without peat. Casing soil with 70% peat harbored higher bacterial richness, enriched beneficial taxa such as Paenisporosarcina , enhanced chemoheterotrophy and nitrogen fixation functions, and more deterministic community assembly compared with other treatments. The bacterial ecological network in casing soil with 70% peat also showed the highest average connectivity, shortest average path length, and strongest robustness. Further, soil physical properties had a greater influence on bacterial community structure in the casing soil than chemical properties. Soil density, available phosphorus and potassium significantly influenced the bacterial community in the 70% peat group. Conclusion Together, this study suggested that peat promoted O. raphanipes production by regulating the casing soil microbiome, providing a theoretical basis for optimizing practical cultivation strategies.