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Researching methods for harmless and resourceful utilization of phosphate mine tailings presents a new approach to addressing phosphate mine tailings pollution. This study selected a formulation of agents for solidifying fluorine and phosphorus in phosphate mine tailings, investigating the solidification effects of phosphorus and fluorine under different temperatures and time, as well as the changes in the physicochemical properties of phosphate mine tailings. Solidified phosphate mine tailings soilization results showed that phosphate mine tailings: polymerized aluminum sulfate: ferrous sulfate=96.5 : 1.75 : 1.75 worked well, with a leaching toxicity of fluorine of 0.9569 mg/L, a fixation rate of 74.92 %, and a retention of water‐soluble phosphorus of up to 82.75 %. At 25 °C and 28 days of cultivation, the leaching toxicity of phosphate mine tailings treated with the solidifying agent was less. Solidified phosphate mine tailings were again added with solidifying agent to solidify phosphorus and fluorine, and the stabilization rate of fluorine reached 90.08 %. The "soil" cultivated for 28 days had an optimal structure of nutrients, and the germination rate of cabbage seeds was 83.33 %. This study demonstrates the possibility of using phosphate mine tailings as planting soil, and provides a useful theoretical basis for the fluoride fixation mechanism in phosphate mine tailings. [ABSTRACT FROM AUTHOR]

ABSTRACT Soil salinity is a worldwide problem threatening crop yields. Some plant growth‐promoting rhizobacteria (PGPR) could survive in high salt environment and assist plant adaptation to stress. Nevertheless, the genomic and metabolic features, as well as the regulatory mechanisms promoting salt tolerance in plants by these bacteria remain largely unknown. In the current work, a novel halotolerant PGPR strain, namely, Bacillus sp. strain RA can enhance tomato tolerance to salt stress. Comparative genomic analysis of strain RA with its closely related species indicated a high level of evolutionary plasticity exhibited by strain‐specific genes and evolutionary constraints driven by purifying selection, which facilitated its genomic adaptation to salt‐affected soils. The transcriptome further showed that strain RA could tolerate salt stress by balancing energy metabolism via the reprogramming of biosynthetic pathways. Plants exude a plethora of metabolites that can strongly influence plant fitness. The accumulation of myo‐inositol in leaves under salt stress was observed, leading to the promotion of plant growth triggered by Bacillus sp. strain RA. Importantly, myo‐inositol serves as a selective force in the assembly of the phyllosphere microbiome and the recruitment of plant‐beneficial species. It promotes destabilizing properties in phyllosphere bacterial co‐occurrence networks, but not in fungal networks. Furthermore, interdomain interactions between bacteria and fungi were strengthened by myo‐inositol in response to salt stress. This work highlights the genetic adaptation of RA to salt‐affected soils and its ability to impact phyllosphere microorganisms through the adjustment of myo‐inositol metabolites, thereby imparting enduring resistance against salt stress in tomato. [ABSTRACT FROM AUTHOR]

Soil microorganisms play a crucial role in maintaining soil ecosystem health. Their metabolic processes are directly impacted by various environmental stresses caused by the increasing release of chemical pollutants and changes in the physical environment due to rapid societal development. This paper aimed to investigate the mechanisms underlying the changes in soil microbial stress responses under various external environmental stresses. The impact of pollutants on soil ecological structure was analyzed by summarizing the stress response patterns of soil microorganisms to inorganic pollutants, organic pollutants, and extreme physical environmental factors. Additionally, the migration and transformation behaviors of various complex pollutants, facilitated by the involvement of soil microorganisms, were investigated. Moreover, a novel approach was proposed for pollutant control, suggesting that manipulating the external physical field of a certain intensity could guide microbial communities and their functions towards controllable evolution within the soil environment. Therefore, this paper was essential for exploring the diversity of soil microbial stress responses, strategically regulating contaminant transport, mitigating risks associated with soil complexity, and ultimately reshaping soil ecological functions. [ABSTRACT FROM AUTHOR]