Rhizosphere reprogramming by integrated bio‑organic fertilizer and seed coating mitigates atrazine phytotoxicity in...

The widespread use of atrazine in maize fields poses a persistent threat to subsequent soybean production due to its soil persistence and phytotoxicity. Here, we present an integrated field strategy by synergistically combining a vermicompost-based bio-organic fertilizer with a targeted seed coating, both delivering the efficient atrazine‑degrading Paenarthrobacter sp. AT5. This synergy thereby provides a dual guarantee of precise rhizosphere colonization and a conducive soil environment for atrazine degradation. The combined treatment significantly reduced atrazine concentrations in roots, stems, and leaves by 38.8%, 23.2%, and 35.5%, respectively, while elevating hydroxyatrazine to 8.2-31.0 times the levels in the atrazine-only treatment. Soil atrazine residues decreased while hydroxyatrazine accumulated, particularly in the rhizosphere. Microbiome analyses revealed that the combined treatment enriched key bacterial genera, including Flavobacterium and Bacillus, potentially harboring atrazine-degrading capabilities, and increased the abundance of the functional gene trzN. In parallel, it restored deterministic community assembly processes and re-established cooperative interactions within the rhizosphere bacterial network. Together, these findings elucidate the mechanistic basis by which synergistic inoculation mitigates atrazine phytotoxicity under field conditions and highlight a scalable, microbiome-based strategy for sustaining soybean productivity in herbicide-impacted agroecosystems.