Synergistic effects of enhanced biological phosphorus removal microbiomes and arbuscular mycorrhizal fungi on nutrient uptake and growth of Sorghum bicolor

Understanding microbial interactions in soil is crucial for developing biofertilizers in regenerative agriculture. In the Sorghum bicolor rhizosphere, we examined the interactions between arbuscular mycorrhizal fungi (AMF) and microbiomes enriched with polyphosphate-accumulating organisms (PAOs) derived from enhanced biological phosphorus removal (EBPR) biosolids and compost. Using plant biometry and nutrient analyses, ³¹P nuclear magnetic resonance (NMR), single-cell Raman microspectroscopy (SCRS), and soil microbiome profiling, we found PAOs from both sources accumulated polyphosphates in the rhizosphere. However, AMF synergized more effectively with EBPR-derived microbiomes, enhancing sorghum growth, nutrient uptake, and microbial activity in soils while increasing phenotypic diversity and functional resilience. Additionally, the bacterial PAOs, Thauera and Pirellula, along with non PAO genera Nitrosomonas and Aromatoleum, integrated into the sorghum rhizosphere from EBPR systems, showing a strong correlation with plant nutrient uptake. The results highlight the potential of targeted microbial co-inoculation of EBPR microbiomes and AMF for improving sorghum productivity and soil fertility.

解析土壤微生物互作机制，对于再生农业领域生物肥料的研发具有关键意义。本研究以双色高粱（Sorghum bicolor）根际为研究对象，探究了丛枝菌根真菌（arbuscular mycorrhizal fungi, AMF）与分别源自强化生物除磷（enhanced biological phosphorus removal, EBPR）体系生物固体及堆肥的、富集聚磷菌（polyphosphate-accumulating organisms, PAOs）的微生物组之间的互作关系。本研究采用植物生物计量学、营养成分分析、磷-31核磁共振（³¹P nuclear magnetic resonance, NMR）、单细胞拉曼显微光谱（single-cell Raman microspectroscopy, SCRS）以及土壤微生物组谱型分析等技术手段，结果发现两种来源的聚磷菌均可在根际环境中积累多聚磷酸盐。然而，丛枝菌根真菌与强化生物除磷来源的微生物组协同增效效果更为显著，可促进高粱生长、养分吸收与土壤微生物活性，同时提升群落表型多样性与功能韧性。此外，源自强化生物除磷体系的细菌聚磷菌陶厄氏菌属（Thauera）、皮尔鲁拉菌属（Pirellula），以及非聚磷菌属亚硝化单胞菌属（Nitrosomonas）与芳香杆菌属（Aromatoleum）成功定殖于高粱根际，且与植物养分吸收呈现显著相关性。本研究结果表明，定向联合接种强化生物除磷微生物组与丛枝菌根真菌，有望提升高粱生产力与土壤肥力。