Fusarium avenaceum is the predominant fungal pathogen responsible for root rot in Angelica crops and poses a serious threat to their commercial quality and yield in China. This fungus produces enniatin B (ENN B), a toxin that could be a pathogenicity and virulence factor in plant–pathogen interactions. Yet whether ENN B exacerbates host infection and the onset of root rot in Angelica spp. caused by F. avenaceum is surprisingly understudied. Pathogenicity assays revealed that ENN B co-inoculation with F. avenaceum significantly increased the root rot disease index in Angelica sinensis from 83.33% (pathogen alone) to 92.86% (p < 0.05). Toxin degradation experiments showed that the bacteria Paenibacillus polymyxa and Bacillus tequilensis were capable of degrading 60.69% and 70.02% of ENN B, respectively. Response surface optimization (24.5 °C, 22.01 mg/L ENN B, 0.99% inoculum) enhanced degradation by B. tequilensis to 81.94%, a 11.74% improvement. Three ester compounds were identified by LC-HRMS as potential degradation products of ENN B. In planta trials demonstrated that the disease index was 50.01% for the group co-inoculated with ENN B degradation products and F. avenaceum, a 42.85% reduction compared to the group co-inoculated with ENN B and F. avenaceum. This study provides a new microbial strategy for controlling root rot in Angelica crops from a mycotoxin degradation perspective, which can be applied to promote sustainable agricultural production.

Soil salinization impacts over one billion hectares, threatening global food security. Here, a salt-tolerant bacterial strain, Pseudomonas fluorescens G3, was isolated from the rhizosphere of maize (Jinongyu-719) growing in saline–alkali soils in Gansu Province, China. This strain demonstrated the ability to secrete indole-3-acetic acid (IAA), 1-aminocyclopropane-1-carboxylic acid (ACC) deaminase, and extracellular polysaccharides. It also exhibited notable phosphate-solubilizing activity and robust siderophore production capabilities. Under salt stress conditions (200 mM NaCl), the P. fluorescens G3 strain significantly improved maize’s growth parameters, namely its plant height, root length, and dry weight. Further, it enhanced antioxidant enzyme activity while reducing the accumulation of malondialdehyde (MDA), mitigating stress-induced oxidative damage. In P. fluorescens G3-inoculated plants, leaf and root Na⁺ contents decreased by 34.90% and 33.91%, while their K⁺ contents increased by 40.20% and 33.47%, respectively. Inoculation with P. fluorescens G3 enhanced taxonomic richness (ACE, Chao1) and evenness (Shannon, Simpson) in the rhizosphere bacterial community, leading to a significantly greater relative abundance of several bacterial genera: Pseudomonas, Methylophaga, Enhygromyxa, Desulfuromonas, and Devosia. These shifts in the microbial community composition suggest a potential restructuring of functional profiles, possibly enhancing processes beneficial to plant salt tolerance, such as ion homeostasis and stress mitigation: the biosynthesis of cofactors and secondary metabolites; bacterial secretion and two-component systems; porphyrin metabolism; flagellar assembly; biofilm formation; and bacterial chemotaxis. Redundancy analysis revealed positive correlations between microbial composition at both the phylum and genus levels and the activity of stress resistance enzymes after treatment with Pseudomonas fluorescens. This study provides important theoretical foundations and microbial resources for utilizing microbial community regulation in saline–alkali soil bioremediation.