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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]

Ferulic acid (FA) and p-hydroxybenzoic acid (PHBA) are main phenolic compounds accumulated in rhizosphere of continuously cropped cucumber, causing stress in plants. Microbial degradation of a mixture of FA and PHBA is not well understood in soil. We isolated a strain CSY-P13 of Acinetobacter calcoaceticus, inoculated it into soil to protect cucumber from FA and PHBA stress, and explored a mechanism underlying the protection. CSY-P13 effectively degraded a mixture of FA and PHBA in culture solution under conditions of 39.37°C, pH 6.97, and 21.59 g L-1 potassium dihydrogen phosphate, giving rise to 4-vinyl guaiacol, vanillin, vanillic acid, and protocatechuic acid. During FA and PHBA degradation, activities of superoxide dismutase (SOD), catalase, ascorbate peroxidase, and dehydroascorbate reductase in CSY-P13 were induced. Inoculated into cucumber-planted soil containing 220 μg g-1 mixture of FA and PHBA, CSY-P13 degraded FA and PHBA in soil, increased plant height, and decreased malonaldehyde, superoxide radical, and hydrogen peroxide levels in leaves. CSY-P13 also enhanced SOD, guaiacol peroxidase, catalase, glutathione peroxidase, ascorbate peroxidase, monodehydroascorbate reductase, dehydroascorbate reductase, and glutathione reductase activities; increased ascorbate and glutathione contents; and elevated transcript levels of copper/zinc SOD, manganese SOD, and catalase in leaves under FA and PHBA. Moreover, CSY-P13 increased phosphatase, catalase, urease, and sucrase activities and changed bacterial richness, diversity, and community composition by high throughput sequencing in cucumber-planted soil supplemented with the mixture of FA and PHBA. So CSY-P13 degrades the mixture of FA and PHBA in soil and mitigates stress from the two phenolic compounds in cucumber by activating antioxidant enzymes, changing soil bacterial community, and inducing soil enzymes. [ABSTRACT FROM AUTHOR]

Fluorine pollution has become one of the key issues of water pollution, and the adsorption materials for efficient removal of fluorine ions have attracted much attention. It is rarely reported that the self-synthesized biomass materials were functionalized by the β-CD@Ce(NO) 3. This paper mainly proposed a new synthetic method of the self-synthesized biomass materials were modified by the β-CD@Ce(NO) 3 and removal of fluorine ions. The effects of this materials on the adsorption efficiency of fluorine ions under different conditions were explored, and the kinetic and thermodynamic simulations were carried out. The results show that the self-synthesized biomass materials were modified by the β-CD@Ce(NO) 3 has significant pore structure, large specific surface area and multi-functional group. Adsorption experiment showed that the reaction reached adsorption equilibrium at 30 min. The removal rate of fluorine ions reached 93.13%, and the fluorine ions adsorption capacity was 37.25 mg/g under neutral conditions. The material can be recycled for more than 5 times, and the adsorption efficiency remains above 94%. The adsorption kinetics accorded with the pseudo second-order model and the adsorption isotherm equation is in line with the Langmuir isotherm adsorption model. PO 4 3− and CO 3 2− have the most impact on fluorine ions adsorption. This method reduces the synthesis cost of high-performance adsorption materials and improves the adsorption performance, which is conducive to the popularization and application in the future. [Display omitted] • A simple and economical method was used for defluorination of wastewater. • Nano Biomass Material functionalized by β-CD@Ce(NO)3 were efficient for the removal of low fluoride content. • Fluoride removal occurred simultaneously by ion exchange, ligand exchange, complexation and electrostatic interaction. • This method breaks the limitation of organic waste in application. [ABSTRACT FROM AUTHOR]