Pleurotus ostreatus cultivation is often affected by pest infestations, which contaminate the bag by eating nutrients and mycelium. This contamination eventually leads to a decline in the quality and yield of edible mushrooms and affects farmers’ income. Therefore, pesticides are commonly used for pest control. To examine the impact of insecticides on the growth of P. ostreatus, this study quantified the activities of antioxidant enzymes, including catalase (CAT), peroxidase (POD), superoxide dismutase (SOD), and phenylalanine deaminase (PAL), in the mushroom under different insecticide treatments. Additionally, transcriptome sequencing was performed to investigate the underlying regulatory mechanisms. The findings indicated that dinotefuran, diflubenzuron, chlorantraniliprole, and beta-cypermethrin treatments resulted in a significant reduction in catalase and peroxidase activities in P. ostreatus. Conversely, the application of beta-cypermethrin and chlorantraniliprole significantly enhanced PAL and SOD activities in the mycelium. PAL activity was significantly increased in all the mixed substrates, whereas only spray treatments with diflubenzuron resulted in a significant increase in PAL activity. SOD activity in the substrates was reduced by diflubenzuron in the mixed treatment and chlorantraniliprole in the spray treatment. In contrast, all other treatments resulted in a significant increase in SOD activity in the substrates. Transcriptome sequencing revealed that differential genes were predominantly enriched in valine, leucine, and isoleucine degradation, fatty acid degradation, tyrosine metabolism, ascorbate and aldarate metabolism, and histidine metabolism, among others. These biological processes are hypothesized to be involved in the growth regulatory effects of insecticides on the mycelium and ascospores of P. ostreatus. The reliability of the transcriptomic data was also validated through quantitative real-time polymerase chain reaction.

The return of mushroom residue to the field is an effective measure to improve soil fertility and maintain agroecosystem productivity. We investigated the effects of returning Auricularia auricula residue to the field on the soil nutrients, enzyme activities, and microbial communities in rice–A. auricula rotation farmland. The return of 67.5 ton/ha A. auricula residue to the field significantly increased the contents of ammonium nitrogen, total nitrogen, total potassium, total phosphorus, available potassium (QK), available phosphorus, and organic matter by 180.49%, 70.41%, 16.3%, 54.35%, 137.33%, 38.84%, and 59.29%, respectively. The activities of urease, sucrase, β-glucosidase (β-GC), and acetyl-β-d-glucosidase significantly increased by 32.98%, 407.78%, 206.85%, and 186.26%, respectively; catalase and leucine aminopeptidase activities increased by 244.42% and 130.90% with the return of 54 ton/ha residue. Mushroom residue return increased the Chao1 and Shannon indices of the bacterial community but decreased the diversity of the fungal community. Redundancy analysis showed that QK, β-GC, and urease were closely associated with shifts in microbial community structure. Therefore, returning 67.5 ton/ha (149,925 bags) A. auricula residue to the field can enhance soil ecological functions by improving soil nutrients, enzyme activities, and microbial community structure.