Effects of peach tree root extracts on the growth of replanted peach tree and soil microbial community
摘要
【Objective】Peach [Prunus persica (L.) Batsch] is a globally cultivated fruit crop and possesses high economic importance. However, continuous monocropping frequently leads to peach replant disease, a pervasive problem characterized by inhibited seedling growth, rhizosphere disorder, reduced productivity, and orchard degradation. Increasing evidence suggests that allelopathic autotoxic substances released from senescent root residues may act as key triggers, inducing shifts in rhizosphere microbial composition, suppressing nutrient cycling, and negatively affecting plant physiological processes. Nevertheless, the comprehensive spectrum of peach root-derived autotoxic metabolites and their cascading effects on rhizosphere microecology and seedling development remain insufficiently characterized. This study aimed to elucidate the composition of autotoxic allelochemicals in peach roots, evaluate their impacts on soil nutrient availability, microbial community dynamics, and photosynthetic and morphological performance of peach seedlings, and clarify their potential role in the development of peach replant disorder. The findings are intended to support mechanistic interpretation and provide a theoretical foundation for designing effective replant mitigation strategies.【Methods】Root samples were collected from an aged peach orchard and processed into high(1∶10)and low(1∶40)concentra tion aqueous extracts. Non-targeted metabolomic profiling was conducted using a mass spectrometrybased platform to identify autotoxic compounds present in peach roots. A pot experiment was established using distilled water as the control to assess rhizosphere soil properties and seedling responses under extract treatment. Soil enzyme activity(urease)was determined via a colorimetric assay. Available phosphorus and potassium were quantified using flame photometry, soil organic matter content was assessed using an oxidation method, and available Fe, Mn, and Zn were determined via atomic absorptio