In order to compare the differences in growth and secondary metabolite accumulation of Panax quinquefolius between understory and field planting, growth indexes, photosynthetic characteristics, soil enzyme activities, secondary metabolite contents, and antioxidant activities of P. quinquefolius under different planting modes were examined and compared, and One-way analysis of variance(ANOVA) and correlation analyses were carried out by using the software SPSS 25.0 and GraphPad Prism 9.5. The Origin 2021 software was used for plotting. The results showed that compared with those under field planting, the plant height, leaf length, leaf width, photosynthetic rate, and chlorophyll content of P. quinquefolius under understory planting were significantly reduced, and arbuscular mycorrhizal fungi(AMF) infestation rate and infestation intensity, ginsenoside content, and antioxidant activity were significantly increased. The activities of inter-root soil urease, sucrase, and catalase increased, while the activities of non-inter-root soil urease and alkaline phosphatase increased. Correlation analyses showed that the plant height and leaf length of P. quinquefolius plant were significantly positively correlated with net photosynthetic rate, transpiration rate, chlorophyll content, and electron transfer rate(P<0.05), while ginsenoside content was significantly negatively correlated with net photosynthetic rate, chlorophyll content, and electron transfer rate(P<0.05) and significantly positively correlated with AMF infestation rate and infestation intensity(P<0.05). In addition, ginsenoside content was significantly positively correlated with the activities of inter-root soil sucrase, urease, and catalase(P<0.05). This study provides basic data for revealing the mechanism of secondary metabolite accumulation in P. quinquefolius under understory planting and for exploring and practicing the ecological mode of P. quinquefolius under understory planting.
Panax/microbiology* ; China ; Secondary Metabolism ; Soil/chemistry* ; Photosynthesis ; Plant Leaves/metabolism* ; Chlorophyll/metabolism* ; Mycorrhizae

To investigate the effects of phosphorus fertilizer on the morphological traits, active ingredients and rhizosphere soil microbial community of Polygala tenuifolia. The phosphorus fertilizer was calculated in terms of P_2O_5. Five treatments were set up: 0(CK), 17(P1), 34(P2), 51(P3), and 68(P4) kg per Mu(1 Mu≈667 m~2). A randomized block design was adopted. Samples of P. tenuifolia and its rhizosphere soil were collected under different superphosphate fertilizer treatments. Illumina high-throughput sequencing was used to analyze the rhizosphere soil microbial community, 9 morphological traits were measured and the content of 11 active ingredients were determined. The results showed that the whole plant weight, shoot fresh weight, root weight, and root peel thickness were the highest under P1 treatment, increasing by 34.41%, 38.80%, 39.21%, and 3.17% respectively compared to CK. Under P2 treatment, the plant height, stem diameter, root thickness, and core thickness were significantly higher than CK. Phosphorus fertilizer had a significant impact on the content of tenuifolin, sibiricose A5, sibiricose A6, arillanin A, 3,6'-disinapoyl sucrose, and polygalaxanthone Ⅲ. Correlation analysis results showed that the relative abundance of Arthrobacter, Bacillus, norank＿f＿Vicinamibacteraceae, norank＿o＿Vicinamibacterales, MND1 and other bacteria, as well as the relative abundance of Neocosmospora, Paraphoma and other fungi were positively correlated with root diameter, wood core diameter, the whole plant weight, root weight, shoot fresh weight of P. tenuifolia. Bacillus, Neocosmospora, Subulicystidium were significantly positively correlated with oligosaccharides such as 3,6'-disinapoyl sucrose, sibiricose A5、sibiricose A6、glomeratose A、arillanin A and tenuifoliside C. Arthrobacter, Humicola, Aspergillus, Paraphoma were positively correlated with tenuifolin and norank＿f＿Vicinamibacteraceae, norank＿o＿Vicinamibacterales, Fusarium were positively correlated with polygalaxanthone Ⅲ. Evidently, appropriate phosphorus application is conducive to the growth and quality improvement of P. tenuifolia, and can increase the abundance of beneficial microorganisms in the soil.
Rhizosphere ; Phosphorus/pharmacology* ; Soil Microbiology ; Polygala/anatomy & histology* ; Fertilizers/analysis* ; Bacteria/metabolism* ; Soil/chemistry* ; Microbiota/drug effects* ; Plant Roots/metabolism*

Mercury (Hg)-contaminated soil poses a significant threat to the environment and human health. Hg-resistant microorganisms have the ability to survive under the stress of inorganic and organic Hg and effectively reduce Hg levels and toxicity. Compared to physical and chemical remediation methods, microbial remediation technologies have garnered increasing attention in recent years due to their lower cost, remarkable efficacy, and minimal environmental impact. This paper systematically elucidates the molecular mechanisms of Hg resistance in microbes, with a focus on their potential applications in phytoremediation of Hg-contaminated soils through plant-microbe interactions. Furthermore, it highlights the critical role of microbes in enhancing the effectiveness of transgenic plants for Hg remediation, aiming to provide a theoretical foundation and scientific basis for the bioremediation of Hg-contaminated soils.
Mercury/toxicity* ; Biodegradation, Environmental ; Soil Pollutants/isolation & purification* ; Soil Microbiology ; Plants, Genetically Modified/metabolism* ; Bacteria/genetics*

Phages, as obligate bacterial and archaeal parasites, constitute a virus group of paramount ecological significance due to their exceptional abundance and genetic diversity. These biological entities serve as critical regulators in Earth's ecosystems, driving biogeochemical cycles, energy fluxes, and ecosystem services across terrestrial and marine environments. Within soil microbiomes, phages function as microbial "dark matter," maintaining the soil-plant system balance through precise modulation of the microbial community structure and functional dynamics. Despite the growing research interests in soil phages in recent years, the proportion of such studies in environmental virology remains disproportionately low, which is primarily attributed to researchers' limited familiarity with the research methodologies for phage microecology, incomplete technical frameworks, and inherent challenges posed by soil environmental complexity. To address these challenges, this review synthesizes cutting-edge methodologies for soil phage investigation from four aspects: (1) tangential flow filtration (TFF)-based phage enrichment strategies; (2) integrated quantification approaches combining double-layer agar plating, epifluorescence microscopy, and flow cytometry; (3) multi-omics analytical pipelines leveraging metagenomics and viromics datasets; and (4) computational frameworks merging machine learning algorithms with eco-evolutionary theory for deciphering phage-host interaction networks. Through comparative analysis of methodological principles, technical merits, and application scopes, we establish a comprehensive workflow for soil phage research. Future research in this field should prioritize: (1) construction of soil phage resource libraries, (2) exploration of RNA phages based on transcriptomes, (3) functional characterization of unknown genes, and (4) deep integration and interaction validation of multi-omics data. This systematic methodological synthesis provides critical technical references for addressing fundamental challenges in characterizing soil phages regarding the community structure, functional potential, and interaction mechanisms with hosts.
Bacteriophages/physiology* ; Soil Microbiology ; Ecosystem ; Microbiota ; Metagenomics/methods*

Three soil conditioners were prepared from granulated food waste and decomposed cattle manure combined with desulfurization gypsum, coal gangue, and maifanite, respectively. Field trials were conducted in the saline field growing Cabernet Sauvignon. The effects of soil conditioners on rhizospheric bacterial communities were studied, with the aim of providing a scientific basis for soil amelioration and restoration. Five treatments were designed, including the control (T1), conventional fertilization (T2), reduced chemical fertilization+organic matter-based soil conditioner with calcium additives (T3), reduced chemical fertilization+organic matter-based soil conditioner with silica additives (T4), and reduced chemical fertilization+organic matter-based soil conditioner with magnesium additives (T5), each with three replications. The results indicated that soil conditioners improved the rhizospheric nutrients, yield, and quality of grape (P<0.05), increased relative abundance of Proteobacteria by 17.32%-23.37%, decreased relative abundance of unidentified_Bacteria and Acidobacteriota by 4.22%-28.42% and 20.88%-35.81%, respectively. The bacterial community composition and diversity were different between treatments. Function analysis showed that the expression levels of the genes involved in chromosome and protein synthesis, mRNA biosynthesis, and glyoxylate and dicarboxylate metabolism were up-regulated in the treatments with soil conditioners. The correlation analysis revealed that multiple environmental factors affected the alpha diversity of rhizospheric bacterial communities, and some bacterial taxa were closely related to the grape yield and quality. It is concluded that soil conditioners can effectively alter rhizosphere nutrient levels and bacterial community structures and functions. T5 treatment outperforms other treatments in improving the physico-chemical and biological characteristics of rhizosphere, and the yield, and quality of grape. It has potential for application, and provides an important basis for development of new-type soil conditioners.
Soil Microbiology ; Rhizosphere ; Soil/chemistry* ; Vitis/microbiology* ; Fertilizers ; Bacteria/growth & development* ; Cattle ; Manure ; Animals

The regulation of rhizosphere bacterial community structure and metabolism by plants in municipal solid waste landfills is a key to enhancing the biodegradation of chlorobenzene (CB). In this study, we employed biodiversity and metabolomics methods to systematically analyze the mechanisms of different plant species in regulating the rhizosphere bacterial community structure and metabolic features and then improved the methane (CH₄) oxidation and CB degradation capacity. The results showed that the rhizosphere soil of Rumex acetosa exhibited the highest CH₄ oxidation and CB degradation capacity of 0.08 g/(kg·h) and 1.72×10^-6 g/(L·h), respectively, followed by the rhizosphere soil of Amaranthus spinosus L., with the rhizosphere soil of Broussonetia papyrifera showing the weakest activity. Rumex acetosa promoted the colonization of Methylocaldum in the rhizosphere, and the small-molecule organic amine, such as triethylamine and N-methyl-aniline, secreted from the roots of this plant enhanced the tricarboxylic acid cycle and nicotinamide metabolism, thereby increasing microbial activity and improving CH₄ and CB degradation efficiency. Conversely, cinnamic acid and its derivatives secreted by Broussonetia papyrifera acted as autotoxins, inhibiting microbial activity and exacerbating the negative effects of salt stress on key microbes such as methanotrophs. This study probed into the mechanisms of typical plants growing in landfill cover soil in regulating bacterial ecological functions, offering theoretical support and practical guidance for the plant-microbe joint control of landfill gas pollution.
Biodegradation, Environmental ; Rhizosphere ; Soil Microbiology ; Waste Disposal Facilities ; Chlorobenzenes/metabolism* ; Bacteria/metabolism* ; Soil Pollutants/metabolism* ; Methane/metabolism* ; Plant Roots/microbiology* ; Amaranthus/microbiology* ; Soil

The biological nitrogen removal technology utilizing heterotrophic nitrification-aerobic denitrification (HN-AD) bacteria has shown effectiveness in wastewater treatment. However, the nitrogen removal efficiency of HN-AD bacteria significantly decreases as the salinity increases. To tackle the challenge of treating high-salt and high-nitrogen wastewater, we isolated a moderately halophilic HN-AD strain 5505 from a salt lake in Xinjiang. The strain was identified based on morphological, physiological, and biochemical characteristics and the 16S rRNA gene sequence. Single-factor experiments were carried out with NH₄⁺-N, NO₃^--N, and NO₂^--N as sole or mixed nitrogen sources to study the nitrifying effect, denitrifying effect, and nitrogen metabolism pathway of the strain. The strain was identified as Halomonas sp.. It can grow in the presence of 1%-25% (W/V) NaCl and exhibited efficient nitrogen removal ability in the presence of 3%-8% NaCl. At the optimal NaCl concentration (8%), the strain showed the NH₄⁺-N, NO₃^--N and NO₂^--N removal rates of 100.0%, 94.11% and 74.43%, respectively. Strain 5505 removed inorganic nitrogen mainly by assimilation, which accounted for over 62.68% of total nitrogen removal. In the presence of mixed nitrogen sources, strain 5505 showed a preference for utilizing ammonia, with a potential HN-AD pathway of NH₄⁺→NH₂OH→NO₂^-→NO₃^-→NO₂^-→NO/N₂O/N₂. The findings provide efficient salt-tolerant bacterial resources, enhance our understanding of biological nitrogen removal, and contribute to the nitrogen removal efficiency improvement in the treatment of high-salt and high-nitrogen wastewater.
Halomonas/classification* ; Nitrogen/isolation & purification* ; Denitrification ; Nitrification ; Wastewater/microbiology* ; Aerobiosis ; Biodegradation, Environmental ; Salinity

Chlorobenzene contaminants (CBs) pose a threat to the eco-environment, and functional strains hold considerable potential for the remediation of CB-contaminated sites. To deeply explore the application potential of functional bacteria in the in-situ bioremediation of CBs, this study focused on the biodegradation characteristics and degradation kinetics of CB and 1, 2-dichlorobenzene (1, 2-DCB) in soil by the isolated strain Serratia marcescens TF-1. Additionally, an in-situ remediation trial was conducted with this strain at a chemical industrial site. Batch serum bottle experiments showed that the degradation rate of CB at the concentrations ranging from 20 to 200 mg/L by TF-1 was 0.22-0.66 mol/(g_cell·h), following the Haldane model, with the optimal concentration at 23.12 mg/L. The results from simulated soil degradation experiments indicated that the combined use of TF-1 and sodium succinate (SS) significantly enhanced the degradation of CBs, with the maximum degradation rate of CB reaching 0.104 d^-1 and a half-life of 6.66 d. For 1, 2-DCB, the maximum degradation rate constant was 0.068 7 d^-1, with a half-life of 10.087 d. The in-situ remediation results at the chemically contaminated site demonstrated that the introduction of bacterial inoculant and SS significantly improved the removal of CBs, achieving the removal rates of 84.2%-100% after 10 d. CB, 1, 4-dichlorobenzene (1, 4-DCB), and benzo[a]pyrene were completely removed. Microbial diversity analysis revealed that the in-situ remediation facilitated the colonization of TF-1 and the enrichment of indigenous nitrogen-fixing Azoarcus, which may have played a key role in the degradation process. This study provides a theoretical basis and practical experience for the in situ bioremediation of CBs-contaminated sites.
Chlorobenzenes/isolation & purification* ; Biodegradation, Environmental ; Soil Pollutants/isolation & purification* ; Serratia marcescens/metabolism* ; Industrial Waste ; Soil Microbiology

Environmental Microbiology, as a compulsory foundational course for the major of environmental and ecological engineering. Its knowledge system not only lays a profound theoretical foundation but also evinces a close-knit nexus to practical applications in environmental protection and ecological restoration. This course thus serves as an outstanding platform facilitating both teaching reforms and practical innovations of professional courses. With Environmental Microbiology as a paradigmatic illustration, this paper concentrates on addressing issues like archaic course contents and enervating teaching approaches, with the aspiration of augmenting students' professional acuities, practical dexterities, and innovation and entrepreneurial aptitudes. In light of the aforesaid aim, we initiated an all-encompassing probe into the teaching reform and practicable paradigms from the perspective of amalgamating professional education with innovation-steered stratagems. Across multiple fronts, comprehensive reformative undertakings were implemented, subsuming the optimization and reconfiguration of course contents, the exploration of sundry teaching methodologies, and the scientific erection of an evaluation system. Ultimately, a nascent teaching model dubbed "three-dimensional, six-loop and five-collaborative" was formed. This series of comprehensive and innovative reform measures has not only substantially augmented the profundity and extensiveness of professional knowledge, permeating into the core of disciplinary essence, but also remarkably bolstered students' practical operational capabilities and innovative thinking patterns, thereby catalyzing their transformation into well-rounded individuals with a competitive edge. By virtue of these efforts, a solid foundation has been firmly laid for the teaching reform of Environmental Microbiology and the cultivation of high-caliber environmental professionals in the contemporary era, heralding a new chapter in the development of environmental education.
Environmental Microbiology ; Teaching ; Education, Professional/methods* ; Curriculum

In recent years, potato scab caused by pathogenic Streptomyces spp. has become widespread globally, with increasing damage severely compromising the commercial value and storability of tubers. The pathogens are transmitted through the soil and seeds of potato, while existing control technologies have demonstrated limited efficacy in preventing the colonization and spread of pathogens, which pose a critical bottleneck in the sustainable development of the potato industry. This study systematically examines the pathogen characteristics and pathogenic mechanisms, evaluates the impacts of soil nutrients and microbial community structure on disease severity, and analyzes limitations in current chemical control, biological control, and disease-resistant variety breeding approaches. We propose an integrated control strategy of disease-resistant varieties, phosphorus fertilizer reduction, fertilizer efficiency enhancement, and phosphorus-soluble antagonistic fungicides, aiming to provide novel research perspectives for achieving effective prevention and control of potato scab.
Solanum tuberosum/microbiology* ; Plant Diseases/prevention & control* ; Streptomyces/pathogenicity* ; Disease Resistance ; Fungicides, Industrial/pharmacology* ; Fertilizers ; Soil Microbiology