Abstract:In order to clarify the effects of reductive soil disinfestation (RSD) incorporated with different organic materials and Bacillus subtilis inoculant on soil phenolic acids, a field experiment with three treatments, i.e., CK (control without soil treatment), MO (RSD incorporated with 6 t/hm2fermentation waste liquid from sugar industry), and SB (RSD incorporated with 15 t/hm2 plant residues), was performed on Longya Lily cultivated soils in Yuanjiang City, Hunan Province. Each soil treatment was subsequently split into two sub-plots for the inoculation of B. subtilis Y25 (CK_Y25, MO_Y25, SB_Y25) after replanted Longya Lily emergence. Soil samples were collected at post-RSD treatment, growth and harvest stages of replanted Longya Lily, and high performance liquid chromatography (HPLC) was used to analyze soil phenolic acids. Results showed that SB significantly (P<0.05) altered soil phenolic acids patterns, and increased the contents of syringic acid, p-coumaric acid, ferulic acid and total phenolic acids as compared to CK, while MO had no significant effect on the composition and content of soil phenolic acids. The contents of phenolic acids in the RSD-treated soils were increased by Longya Lily replantation, but MO and SB showed different dynamic patterns with the growth of replanted Longya Lily. B. subtilis Y25 inoculant could significantly (P<0.05) reduce the contents of phenolic acids in SB-treated soil, with the degradation rate higher than 30%. In particular, the degradation rates of p-coumaric acid and ferulic acid were as high as 39.2%-47.8% and 32.3%-36.7% at the growing and harvest stages of replanted Longya Lily, respectively. In conclusion, RSD with plant residues as organic materials can increase the content of soil phenolic acids, while the introduction of exogenous microorganism with phenolic acid-degradation function can be used as an effective supporting measure to reduce soil phenolic acids after reductive soil disinfestation.