Global climate change and invasive plants significantly impact biodiversity and ecosystem functions. This study focuses on the effects of progressive warming on microbial communities within the Solidago canadensis invasion community, simulated through six stages of invasion progression, from minimal to dominant S. canadensis presence alongside native Artemisia argyi, in bulk soils collected from a natural habitat and cultivated under controlled greenhouse conditions. Utilizing high-throughput sequencing and microbial community analysis on 72 samples collected from the S. canadensis invasion community, the shifts in soil microbiota under varying warming scenarios were investigated (+0 °C, +1.15 °C and +1.86 °C). We observed significant shifts in invasion community soil bacteria in response to warming, with Acidobacteria, Actinobacteria, and others showing distinct responses between baseline and warmed conditions, while groups like Chlorobi and Cyanobacteria only differed significantly at higher temperature extremes. The random forests algorithm identified 14 taxa as biomarkers and a model was established to correlate S. canadensis invasion community soil microbiota with progressive warming. Co-occurrence network analysis revealed that moderate warming enhances microbial connectivity and the presence of a super-generalist, ASV 1160. However, further warming disrupts these networks by eliminating key generalists, revealing a potential reduction in network stability and diversity. These findings illuminate the dynamic responses of microbes in S. canadensis invasion community soil to varying temperature regimes, suggesting a model for successional dynamics and offering a deeper comprehension of microbial community shifts amid climatic fluctuations. This study delineates how warming significantly reshapes the soil microbial composition, potentially impacting S. canadensis’s invasion success unfavorably, thereby highlighting the importance of considering microbial dynamics in ecological management.

The role of rhizosphere bacteria in facilitating plant invasion is increasingly acknowledged, yet the influence of specific microbial functional traits remains insufficiently understood. This study addresses this gap by isolating two bacterial strains, Bacillus sp. ScRB44 and Pseudomonas sp. ScRB22, from the rhizosphere of the invasive weed Solidago canadensis. We assessed their nitrogen utilization capacity and indoleacetic acid (IAA) production capabilities to evaluate their ecological functions. Our three-stage experimental design encompassed strain promotion, nutrient stress, and competition phases. Bacillus sp. ScRB44 demonstrated robust IAA production and significantly improved the nitrogen utilization efficiency, significantly enhancing S. canadensis growth, especially under nutrient-poor conditions, and promoting a shift in biomass allocation toward the roots, thereby conferring a competitive advantage over native species. Conversely, Pseudomonas sp. ScRB22 exhibited limited functional activity and a negligible impact on plant performance. These findings underscore that the ecological impact of rhizosphere bacteria on invasive weeds is closely linked to their specific growth-promoting functions. By enhancing stress adaptation and optimizing resource allocation, certain microorganisms may facilitate the establishment of invasive weeds in adverse environments. This study highlights the significance of microbial functional traits in invasion ecology and suggests novel approaches for microbiome-based invasive weed management, with potential applications in agricultural soil health improvement and ecological restoration.