Soil salinization seriously inhibits crop growth and damages soil structure, which is the main abiotic stress affecting global agricultural sustainable development and soil ecological health. As the "second genome" of plants, the rhizosphere and endophytic microorganisms form a mutually beneficial symbiotic relationship with plants, which can promote plant growth and enhance their stress resistance, and has important development potential. Halophytes have long adapted to high salt environments, and their rhizosphere and endophytic microbiota have formed strong salt tolerance characteristics, making them a natural treasure trove for exploring salt tolerant and plant growth-promoting microbes. The mechanism by which these microorganisms enhance plant salt tolerance is analyzed from two aspects: their functional characteristics (e.g., production of plant growth hormones, ACC deaminase, and extracellular polysaccharides) and plant responses (e.g., osmotic regulation, antioxidant defense, and ion homeostasis). This article also explores the potential and preliminary effects of synthetic microbial communities in improving plant salt tolerance, and analyzes their advantages compared with single strains. Finally, focusing on current research issues and future directions, this review aims to provide theoretical references and practical ideas for the exploration and utilization of salt-tolerant plant growth-promoting microbes, the improvement of salt-tolerant crops, and the management of saline-alkali lands.

Aquatic fungi play an essential role in maintaining the biogeochemical cycles and functional stability of lake ecosystems. To elucidate the seasonal dynamics of aquatic fungal communities in alpine lakes and the environmental factors shaping them, water samples from the littoral zone of Nam Co Lake in August 2020 (summer), May 2021 (spring), and October 2021 (autumn) were collected and the communities were analyzed by using ITS1 amplicon sequencing. A total of 5 793 OTUs (17 phyla, 869 genera) were detected in spring, 7 227 OTUs (18 phyla, 892 genera) in summer, and 1 558 OTUs (10 phyla, 188 genera) in autumn, indicating pronounced seasonal variations in community diversity and dominant taxa. Ascomycota dominated in spring and summer (78.10% and 78.79%), whereas Chytridiomycota (37.17%) became dominant in autumn. Redundancy analysis (RDA) revealed that water temperature (R²=0.376, P=0.001), pH (R²=0.147, P=0.038), and total nitrogen (R²=0.263, P=0.019) were the primary environmental factors shaping community structure, whereas α-diversity was significantly correlated with total phosphorus and total nitrogen (P<0.05). The neutral community model suggested that stochastic processes dominated in spring (R²=77.4%, Nm=11, 736) but weakened in summer and autumn (R²=14.7% and 8%, respectively), with a relatively low overall goodness of fit (R²=19.1%). Checkerboard score analysis (SES>2) further demonstrated that deterministic processes exerted a predominant influence on community assembly. Overall, aquatic fungal communities in the littoral zone of Nam Co Lake exhibited pronounced seasonal dynamics. Their structure and diversity were primarily driven by environmental factors and jointly regulated by deterministic and stochastic processes, with environmental filtering playing a dominant role in community assembly. These findings offer new insights into the seasonal variations, environmental regulation, and assembly mechanisms of aquatic fungal communities in alpine lakes, thereby advancing our understanding of microbial community formation and ecosystem function in high-altitude aquatic environments.

This study aims to investigate the effect ofdominant lactic acid bacteria (LAB) on the quality of silage feed and its genomic characteristics related to lignocellulose degradation and lactic acid metabolism. Four dominant strains of Lacticaseibacillus paracasei, Lactiplantibacillus plantarum, Weissella cibaria, Pediococcus acidilacticiwere isolated from silage feed and then used as microbial additives for a 50-day silage fermentation. The results showed that Lactiplantibacillus plantarum ZR exhibited superior performance compared to other lactic acid bacteria, with better retention of dry matter content and higher cellulase activity. Additionally, harmful substances such as ADF, NDF, and ammonia nitrogen were significantly reduced compared to other treatment groups. The genomic analysis revealed that Lactiplantibacillus plantarum ZR is 3 398 411 bp in length, consisting of 1 chromosome and 6 plasmids, with a GC content of 44.38%. CAZyme analysis indicated that the genome of Lactiplantibacillus plantarum ZR contains 534 CAZyme genes, and 30 genes related to lactic acid synthesis. Comparative genomic analysis revealed the presence of insertions, deletions, and inversions in the genome of Lactiplantibacillus plantarum ZR, involving genes such as scrR, bglA, malL, galE, agrA, oppA, opuA and others. In conclusion, this study elucidates that Lactiplantibacillus plantarum ZR exhibiting robust silage fermentation capabilities. Additionally, it reveals the genomic characteristics of the strain Lactiplantibacillus plantarum ZR. These findings provide a theoretical basis for the application of this strain at an industrial level.

The Tarim River Basin is rich in microbial resources. To explore the species diversity of Actinoplanes in its soil, uncover new Actinoplanes resources, and enrich the germplasm resource bank of the Tarim River Basin, the in situ enrichment of Actinoplanes was achieved using polyaspartic acid water-retaining agent (PASP). The fermentation crude extracts of Actinoplanes were screened for antimicrobial activity using seven pathogenic bacteria as target strains. This was combined with antiSMASH gene cluster analysis and detection of antibiotic biosynthesis genes. The results indicate that 244 strains isolated and identified from soil samples enriched in situ with PASP belong to 3 phyla, 5 classes, 4 orders, 11 families, 16 genera, and 59 species, respectively. Among these, 228 strains belong to the phylum Actinomycetota, accounting for 93%. The genus Actinoplanes exhibited a high isolation rate, with 103 isolated strains and 21 species, representing 42%. Seven strains of Actinoplanes with both antimicrobial activity and metabolic potential were screened. Soil samples with high moisture content along the Tarim River harbor abundant rare actinobacterial resources. The PASP in situ enrichment method can selectively isolate Actinoplanes, thereby facilitating further research on the diversity of rare actinobacteria in the soil microorganisms of the Tarim River Basin and on the exploration and utilization of Actinoplanes resources.

This study aimed to achieve three primary objectives: (1) to isolate high-performance biofilm-forming microalgal strains through systematic phenotypic screening;(2) to characterize the structural and functional properties of their extracellular polymeric substances (EPS) using integrated spectroscopic techniques; and (3) to demonstrate the practical applications of these biopolymers in microalgal biomass harvesting and antibiotic removal. The experimental approach integrated microbial isolation methods with advanced material characterization and environmental biotechnology strategies. A high-performance biofilm-forming algal strain was isolated based on its wall-adhesion capacity and taxonomically identified. Various EPS extraction protocols were systematically evaluated to determine the most effective method, and structural analysis was conducted using Fourier-transform infrared spectroscopy (FTIR). The functional properties of the extracted EPS were assessed through flocculation assays, antibacterial zone tests, and high-performance liquid chromatography (HPLC). Results showed that the isolated strain FJPN1, identified as Chlorella sorokiniana, exhibited exceptional biofilm-forming capability with a wall-adhesion rate of 96.8%. The ion-exchange resin method yielded the highest EPS quantity (295 mg/g), and FTIR analysis revealed the presence of characteristic functional groups in the polysaccharide-protein complexes, including hydroxyl, amino, and glycosidic bonds. Functional studies demonstrated that EPS at a concentration of 0.5 g/L induced a flocculation efficiency of 90.5% in Chlorella vulgaris FACHB-8. Notably, FJPN1 achieved complete removal (100%) of gentamicin and kanamycin at a concentration of 0.5 g/L and retained full removal efficiency in 50% diluted industrial wastewater. Mechanistic analysis confirmed that biosorption mediated by EPS was the dominant removal mechanism. The dual functionality of C. sorokiniana FJPN1, enabling efficient heterospecific microalgal flocculation and selective removal of aminoglycoside antibiotics, highlights its potential as a novel functional bioresource for microalgal biomass harvesting and antibiotic pollution removal.

Polylactic acid (PLA) is widely recognized as one of the most promising biodegradable polymers for replacing conventional petroleum-based plastics. Although PLA is theoretically fully biodegradable, its practical environmental performance is often compromised by slow degradation rates, which may result in secondary pollution. This limitation is largely attributable to the low abundance and restricted distribution of efficient PLA-degrading microorganisms in natural ecosystems. In this study, a PLA-degrading bacterial strain designated as Raoultella ornithinolytica LD-PLA-01was screened, isolated, and identified from soils samples collected in the Yalu River Basin. The PLA degradation performance of this strain was systematically evaluated. Under mesophilic conditions (30 ℃), strain LD-PLA-01 achieved a mass loss of 14.61% in PLA films within 30 days. Scanning electron microscope (SEM), water contact angle (WCA), and Fourier transform infrared (FTIR) spectroscopy analyses of the degraded PLA films revealed pronounced surface erosion, including depressions and cracks. FTIR spectra indicated hydrolytic cleavage of ester bonds (C-O) on the polymer surface, which was accompanied by a marked increase in surface hydrophilicity. Furthermore, lactic acid monomers and low-molecular-weight oligomers were detected among the degradation products. These results demonstrate that R. ornithinolytica LD-PLA-01 strain exhibits considerable potential for PLA biodegradation and may serve as a promising candidate for the biological treatment and environmental management of PLA-based plastic waste.

To diversify the cultivation of Morchella and improve land-use efficiency, this study focused on the soils collected during the primordium formation phase (Pp) and fruiting body formation development phase (Fp) of Morchella development. The physical and chemical properties, enzyme activities, microbial biomass carbon, and other indices of the soil surrounding the roots of Morchella were determined using national standard methods. One-way ANOVA was performed with SPSS, and Pearson correlation analysis was conducted to evaluate relationships between soil indices at the two stages. Results showed that:During the Pp phase, the mixed sowing of Festuca sinensis with Morchella (F) significantly elevated soil alkali-hydrolysable nitrogen (AN) and the activity of glycoside-hydrolases; the mixed sowing of Vicia sativa with Morchella (V) significantly increased soil dissolved organic carbon (DOC) and β-1, 4-glucosidase (βG) activity; the mixed sowing of Poa pratensis with Morchella (P) significantly raised β-1, 4-N-acetylglucosaminidase (NAG) activity; all herb-Morchella mixed sowing treatments significantly reduced soil microbial biomass carbon (MBC). During the Fp phase, the F group significantly increased MBC content, while the mixed sowing of Medicago sativa with Morchella (M), as well as the F and V groups, significantly decreased microbial biomass phosphorus (MBP) content. Compared with the Pp phase, soil available manganese (AMn), available copper (ACu), available zinc (AZn), and the activities of catalase (CAT), protease (PA), and glycoside-hydrolases all declined markedly in the Fp phase, with most indices falling to less than 50% of their initial levels. Soil alkaline phosphatase (AKP), urease (UR) and pH were negatively correlated with all other indices, whereas remaining soil enzymes showed positive correlations. Microbial biomass elements (MBC, MBN and MBP) were positively correlated with available trace elements (AMn, ACu and AZn). In addition, Morchella yield was positively correlated with soil organic matter (SOM), AN, AZn and UR, but negatively correlated with DOC, ACu, pH and CAT. PCA dimensionality reduction revealed that, during the Pp phase, all mixed sowing treatments elevated soil nutrients (SN) and soil enzyme (SE) activities while suppressing soil microorganisms (SM). In contrast, during the Fp phase, these mixed sowing accelerated the decline of SN. Moreover, SN, SM and SE were significantly positively inter-correlated. The mixed sowing of Morchella with plants is becoming increasingly popular; this study provides a reference for further research on mixed sowing of Morchella and herbaceous species.

Soil salinization threatens approximately 20% of irrigated cropland globally. Conventional physical and chemical remediation methods are limited by high water consumption, significant costs, and environmental risks. Rhizosphere microorganisms, often termed as the plant's "second genome," enhance plant salinity tolerance through multidimensional synergistic mechanisms, which offering a sustainable and efficient strategy for saline soil amelioration. This review delineates plant salt tolerance mechanisms and systematically elucidates the role of rhizosphere microorganisms in regulating this tolerance, including regulating ion stabilization, maintaining osmotic balance, defensing oxidative stress, modulating phytohormone network, improving rhizosphere microhabitat and activating nutrient element. Additionally, the review further discusses the current applications in main crops, such as rice, wheat, maize, soybean, and vegetables. Meanwhile, to address persistent challenges such as inadequate microbial field stability, pronounced host-microbe interaction specificity, and constraints in technology dissemination, future research should prioritize:deepening the interaction of the "plant genotype-root exudate-microbial function" interaction mechanism; utilizing synthetic biology to design functionally complementary Synthetic Microbial Communities (SynComs); enhancing inoculant stability by integrating materials science; and developing smart agricultural technologies for precise application. These integrated strategies are anticipated to facilitate rhizosphere microbe-mediated technologies for saline-alkali land reclamation and large-scale deployment in sustainable agriculture.

Soybean is a vital source of plant-based protein and oil in China, with seed protein and oil contents reaching up to 40% and 20%, respectively. It is also rich in various micronutrients, playing a critical role in both the agricultural production system and the national dietary structure. Microbial inoculants, as functional formulations containing specific active microorganisms, can effectively reduce the use of chemical fertilizers and pesticides by improving soil structure, enhancing microbial diversity, and increasing plant stress resistance. These microbial inoculants significantly promote soybean growth and development, increase yield, and improve nutritional quality. This paper systematically reviews the effects and underlying mechanisms of microbial inoculants on soybean growth, yield formation, and quality enhancement. It also outlines future research directions, aiming to provide theoretical support and practical guidance for improving soybean quality and advancing sustainable agricultural development.

Nucleosides, as the basic structural units of nucleic acid molecules and important biological regulatory factors, have demonstrated extensive application value in multiple fields such as medicine, food, and chemical engineering. Nucleosides' biosynthesis mainly take place through two pathways of de novo synthesis and salvage synthesis. In recent years, with the rapid development of synthetic biology and metabolic engineering technologies, the production efficiency of nucleosides has been significantly improved through strategies such as relief the metabolic regulation of nucleoside-producing bacteria, enhancement of key enzyme expression, and blocking of competitive and degradation pathways. However, the efficient biosynthesis of nucleosides still faces multiple challenges such as insufficient supply of precursors, feedback inhibition, uneven distribution of metabolic flow, and accumulation of potentially toxic products. This article systematically reviews the biosynthetic pathways of nucleosides and focuses on sorting out the latest research progress on metabolic engineering technology in modifying purine nucleoside (adenosine, guanosine, inosine) and pyrimidine nucleoside (cytidine, uridine, thymidine)-producing bacteria. The article delves deeply into the latest achievements in optimizing nucleoside synthesis pathways, enhancing metabolic fluxes, and increasing product accumulation through advanced strategies such as gene editing (like CRISPR/Cas systems), dynamic regulation, promoter engineering, and efflux protein modification. In addition, this paper also analyzes the regulatory mechanism of nucleosides biosynthesis, and in response to the current bottleneck problems, proposes future research directions and technical prospects, aiming to provide theoretical guidance and strategic references for the development of efficient nucleoside engineering strains, with the expectation of accelerating their industrialization process and meeting the increasingly diversified industrial demands.