Search Results (198)

Superabsorbent polymers (SAPs) are increasingly applied in agriculture to enhance soil water retention, reduce nutrient loss, and mitigate drought stress—challenges expected to intensify under global climate change. While their benefits for crop growth are well documented, much less is known about their influence on free-living microorganisms. Here, we examined the effects of three SAP chemistries—potassium polyacrylate (DCM Aquaperla^®), starch-based polyacrylamide (Zeba Plus SP^®), and γ-polyglutamate (Stockosorb^® 660 Medium)—on the growth and pigment composition of Chlorella vulgaris Beijerinck across three initial cell densities (22.8 × 10³, 228 × 10³, and 2.228 × 10⁶ cells/mL). Six spectral indices, derived from weekly absorbance measurements over seven weeks, were used to track biomass and pigment allocation. Nonparametric repeated-measures analysis and principal component analysis revealed strong effects of SAP type, algal density, and time. Zeba consistently maintained biomass comparable to the control while enhancing carotenoid- and xanthophyll-sensitive indices, suggesting pigment reallocation without growth suppression. Stockosorb produced intermediate responses, whereas Aquaperla frequently reduced biomass-related measures, particularly at high density. Pigment allocation was also density-dependent, with low-density cultures investing proportionally more in carotenoids. Overall, these results show that SAP–microbe interactions are strongly influenced by polymer chemistry and starting biomass, with implications for biotechnology, environmental risk assessment, and sustainable crop production systems that aim to support both algal and plant resilience under drought. Full article

Intercropping, especially legume-cereal systems, is a mixed farming approach that can improve agricultural resilience by addressing challenges such as soil degradation, biodiversity loss, and global change, all while promoting the sustainable production of protein-rich and nutritious food. However, its adoption in industrialized countries remains limited due to economic and technical challenges, as well as a fragmented understanding of soil–plant-microbe interactions, which hinders its complete optimization. This article provides an overview of the current situation and future perspectives on the importance of legume–cereal intercropping, with examples such as common bean–maize, soybean–maize, alfalfa–corn–rye, and legumes–pulses–little millet systems. These combinations highlight how intercropping can improve nutrient cycling, increase root growth, forage and grain yield, suppress soil-borne diseases, and promote soil microbial population and enzymatic activity. While it offers environmental benefits, practical challenges such as system design, management complexity, and cost-effectiveness must be addressed to encourage wider adoption. In preparing this review, we synthesized studies published between 2000 and 2025, with a particular emphasis on recent research from China and Southeast Asia. We also considered broader intercropping contexts, including energy crops, agroforestry systems, rice paddy co-cultures, and phytoremediation approaches. The review also highlights legume–cereal as a solution to sustainable soil management, ecosystem health, and the potential for increased nutritional food production in developed countries. Full article

This study presents the design and implementation of a crop environmental monitoring system powered by a plant–soil bioelectrochemical energy source. The system integrates a Cu–Zn electrode power unit, a boost converter, a supercapacitor-based energy management module, and a wireless sensing node for real-time monitoring of environmental parameters. Unlike conventional plant microbial fuel cells (PMFCs), the output current originates partly from the galvanic effect of Cu–Zn electrodes and is further regulated by rhizosphere conditions and microbial activity. Under the optimal external load (900 Ω), the system achieved a maximum output power of 0.477 mW, corresponding to a power density of 0.304 mW·cm⁻². Stability tests showed that with the boost converter and supercapacitor, the system maintained a stable operating voltage sufficient to power the sensing node. Soil moisture strongly influenced performance, with higher water content increasing power by about 35%. Theoretical calculations indicated that Zn corrosion alone would limit the anode lifetime to ~66 days; however, stable output during the experimental period suggests contributions from plant–microbe interactions. Overall, this work demonstrates a feasible self-powered crop monitoring system and provides new evidence for the potential of plant–soil bioelectrochemical power sources in low-power applications. Full article

The integration of leguminous cover cropping systems (LCR), particularly soybean (LC-S) and cowpea (LC-C), into tea agroecosystem provides a sustainable strategy to enhance soil ecosystem services by promoting beneficial soil microbial communities through the modulation of the rhizosphere microbiome in the tea rhizosphere soil. This study employs 16S rRNA gene sequencing to assess how these leguminous cover crops, when incorporated as green manure within the tea row spaces, influence the microbial community diversity in the rhizosphere soil of tea plants. Compared to conventional monoculture tea plantations (CK), the introduction of LC-S and LC-C significantly reshape the microbial communities in the tea rhizosphere soil. They promote the abundance of copiotrophic and specialized taxa such as Proteobacteria, Actinobacteria, and Mycobacterium, which are crucial for nutrient cycling and organic matter decomposition. Additionally, LC-S and LC-C enrich beneficial microbes including Chloroflexi, Bradyrhizobium, Acidothermus, and Cyanobacteria, supporting processes like nitrogen fixation and pathogen suppression. The metagenomic analysis confirms that leguminous cover crops consistently increase bacterial diversity and enrich beneficial phyla vital for soil nutrient dynamics, organic matter breakdown, and environmental stress resilience. Furthermore, microbial genera linked to nitrogen mobilization and complex organic matter degradation are promoted, underpinning the synthesis of nitrogenous compounds (such as theanine, amino acids), polyphenolic secondary metabolites (like flavonoids), and volatile organic compounds essential for tea quality. Functional pathway analyses revealed that LC-S enhances degradation pathways involved in carbohydrate and aromatic compound metabolism, augmenting precursors for key bioactive constituents such as theanine and catechins. Conversely, LC-C favors glycan biosynthesis and degradation pathways, likely improving root–microbe interactions and micronutrient uptake, both critical for polyphenol biosynthesis. Collectively, these microbiome-driven changes improve tea’s sensory qualities, including flavor, aroma, and antioxidant capacity, by enriching bioactive compounds. This microbiome-mediated agro-ecological approach offers a sustainable alternative to conventional monoculture, enhancing soil functionality, ecological resilience, and the economic viability of tea production systems. Full article

Saline–alkali soils in southern Xinjiang present significant challenges for sustainable jujube cultivation, necessitating innovative fertilization strategies to improve soil health and enhance fruit quality. This study investigated the synergistic effects of biochar–nitrogen (N) co-application on soil amelioration and the improvement of jujube quality in saline–alkali jujube orchards. A field experiment was conducted using different biochar application rates (0, BC1, BC2) combined with various N fertilizer types (conventional nitrogen N1, N2, UI-N (urease inhibitor), and NI-N (nitrification inhibitor)), which systematically analyzed soil physicochemical properties, nutrient dynamics, enzyme activities, microbial community structure, and jujube fruit yield and quality parameters. The BC1 biochar application rate emerged as the optimal threshold for soil carbon and N sequestration, with BC1 + N2 treatment achieving the highest total carbon and total nitrogen concentrations, representing increases of 12.4% and 21.42%, respectively, compared to controls. Biochar–N co-application significantly enhanced soil available nutrients, with BC1 + UI-N treatment producing the greatest soil organic matter increase within the BC1 group (9.20–14.51% enhancement). Notably, the treatments modulated soil microelement profiles, suppressing potentially toxic Cu and Mn while enhancing the availability of beneficial Mg and Fe. Soil enzyme activities responded differently, with urease and sucrase activities reaching maximum levels under BC2 + N1 and BC1 + UI-N treatments, respectively. Microbial community analysis revealed that biochar–N combinations significantly restructured both bacterial and fungal communities, with BC1 + NI-N treatment demonstrating superior bacterial α-diversity across all indices. Soil enzyme activities exhibited distinct response patterns, with urease and sucrase activities reaching their peak under the BC2 + N1 and BC1 + UI-N treatments, respectively. Moreover, the co-application of biochar (BC1) with N fertilizer significantly improved fruit performance, increasing per-tree yield by 24.23% and fruit vitamin C content by 16.47%, compared to the control. This study demonstrates that moderate biochar application (BC1) combined with urease inhibitor- enhanced N fertilizer (UI-N) represents an optimal fertilization strategy for saline–alkali jujube orchards, achieving simultaneous soil amelioration and fruit quality enhancement through coordinated regulation of soil–microbe–plant interactions. The established quantitative relationships provide a scientific foundation for the implementation of precision agriculture in arid saline–alkali regions, offering significant implications for sustainable specialty fruit production and soil health restoration in environmentally challenged agricultural systems. Full article

Understanding the regulatory mechanisms of water–nitrogen coupling effects on soil–plant–microbe systems in arid regions is crucial for sustainable agricultural development. This study systematically investigated the interactive effects of field capacity (75% vs. 45%) and nitrogen application rates (100 vs. 300 kg ha⁻¹) combined with different enhanced-efficiency nitrogen fertilizers (EENFs) on rhizosphere soil fertility and microbial community structure of Jujube (Ziziphus jujuba Mill.) seedlings through a two-year pot experiment. Two-year-old jujube seedlings were employed with five treatments: NS (urea), NM (urease inhibitor), XH (nitrification inhibitor), W (microbial fertilizer), and CK (control), to analyze soil physicochemical properties and microbial community responses. Soil available N accumulated under high-N/adequate moisture but declined under drought. NM curbed NH₃ volatilization by 32.38–43.22%, while XH increased NH₄⁺-N by 35.76%. Drought raised microbial α-diversity (bacteria + 33.88–37.5%, fungi + 43.62–68.75%). NM demonstrated optimal performance in ammonia volatilization (32.38–43.22% reduction), while XH showed notable efficacy in ammonium-N regulation (35.76% enhancement). Microbial α-diversity exhibited enhanced responses under drought stress, with bacterial and fungal community improvements reaching 33.88–37.5% and 43.62–68.75%. Redundancy analysis showed environmental factors explained more community variance under water stress (bacteria: 79.19→88.76%; fungi: 64.64→92.52%). These findings provide theoretical support for jujube cultivation in arid zones, demonstrate the potential of targeted EENFs, and offer new insights for precision water–fertilizer and microbial management. Full article

Noccaea species (formerly Thlaspi) are Brassicaceae plants renowned for their capacity to hyperaccumulate zinc (Zn), cadmium (Cd), and nickel (Ni), which has made them model systems in studies of metal tolerance, phytoremediation, and plant adaptation to extreme environments. While their physiological and genetic responses to metal stress are relatively well characterised, the extent to which these traits influence microbiome composition and function remains largely unexplored. These species possess compact genomes shaped by ancient whole-genome duplications and rearrangements, and such genomic traits may influence microbial recruitment through changes in secondary metabolism, elemental composition, and tissue architecture. Here, we synthesise the current findings on how genome size, metal hyperaccumulation, structural adaptations, and glucosinolate diversity affect microbial communities in Noccaea roots and leaves. We review evidence from bioimaging, molecular profiling, and physiological studies, highlighting interactions with bacteria and fungi adapted to metalliferous soils. At present, the leaf microbiome of Noccaea species remains underexplored. Analyses of root microbiome, however, reveal a consistent taxonomic core dominated by Actinobacteria and Proteobacteria among bacterial communities and Ascomycetes, predominantly Dothideomycetes and Leotiomycetes among fungi. Collectively, these findings suggest that metal-adapted microbes provide several plant-beneficial functions, including metal detoxification, nutrient cycling, growth promotion, and enhanced metal extraction in association with dark septate endophytes. By contrast, the status of mycorrhizal associations in Noccaea remains debated and unresolved, although evidence points to functional colonisation by selected fungal taxa. These insights indicate that multiple plant traits interact to shape microbiome assembly and activity in Noccaea species. Understanding these dynamics offers new perspectives on plant–microbe co-adaptation, ecological resilience, and the optimisation of microbiome-assisted strategies for sustainable phytoremediation. Full article

Rice-based co-culture systems offer sustainable agricultural benefits, yet stage-specific impacts on soil properties and grain quality remain underexplored. This study presented the first comprehensive assessment of the stage-specific effects under conventional tillage (CTL), rice-chicken (RC), rice-fish (RF), and rice-chicken-fish (RCF) systems on soil fertility, enzymatic activities, microbial communities, and grain quality. Our novel temporally explicit analysis revealed system- and stage-dependent modulation. RCF increased late-season organic matter by 10.4%, while RC consistently enhanced available potassium. Enzymatic activities exhibited distinct temporal shifts, with RF showing peak catalase activity at heading (0.47 mL g⁻¹ 30 min⁻¹), RC maintaining consistently higher invertase activity, and both RF and RCF displaying delayed urease peaks at filling (0.38 mg g⁻¹ 24 h⁻¹). Microbial communities were significantly restructured (ANOSIM, R² = 0.694, p < 0.001), with increased network complexity in co-cultures, particularly in RCF (95 nodes, 153 edges). Grain quality improvements included higher milling recovery (2.6–5.3%) in RC and elevated protein content (16.6%) in RF and RCF, along with reduced chalkiness (20–30%) across all co-cultures. Integrative analysis established linkages between soil properties (e.g., pH, organic matter, invertase), microbial taxa (e.g., Nitrospira, Syntrophus), and grain quality attributes. These findings provide mechanistic insights into soil-plant-microbe interactions and support the implementation of stage-specific management strategies for sustainable rice production systems. Full article

Constrained by site conditions and water resources, pear tree cultivation faces increasing drought stress. Paecilomyces variotii extract (PVE), a novel biostimulant extracted from wild sea buckthorn root-isolated strains and containing chitin, humic/fulvic acids, and beneficial microbes, has gained attention due to its high activity and efficacy in alleviating plant stresses (e.g., drought). In this study, Pyrus pyrifolia ‘Qiu Yue’ was used as the experimental material, and pot experiments were conducted to examine the drought-mitigating effects of different PVE concentrations. Drought stress was achieved by maintaining soil water content at 35–45% of water holding capacity for 45 days under natural evaporation conditions in rain shelters. The growth status of pear trees, soil enzyme activity, and metabolite levels were analyzed. The results showed that the application of 5 ng/mL PVE promoted pear tree growth, enhanced leaf antioxidant enzyme activity, and improved photosynthetic capacity and soil enzyme activity. Under normal water conditions, the shoot growth length, plant height, stem diameter, and root system activity of the 5 ng/mL PVE group were 31.91%, 12.05%, 3.54%, and 10.94% higher than those of the control group, respectively. Under drought stress, these values increased by 25.12%, 8.87%, 12.21%, and 16.98%, respectively. The addition of 5 ng/mL PVE facilitates trehalose release and upregulates starch-sucrose, glycerophospholipid, and galactose metabolic pathways, thereby potentiating drought stress tolerance in pear trees. However, at 20 ng/mL, reductions were observed in pear tree growth indicators, leaf antioxidant enzyme activity, soil enzyme activity, and trehalose content in root exudates compared to the 5 ng/mL PVE treatment. Overall, 5 ng/mL PVE effectively promotes pear tree growth and enhances drought resistance, making it suitable for broader use in pear cultivation practices. Full article

Plant-to-plant interactions are essential for structuring plant communities and supporting adaptation in nutrient-poor, seasonally dry environments. This study examined the interactions between moss Leucobryum aduncum Dozy & Molk and Oreocharis hainanensis by analyzing microbial communities and physicochemical parameters across various sample types. These included soil [bare (B), O. hainanensis (O), moss (M), and moss + O. hainanensis (MO)], rhizosphere soil [O. hainanensis (ORS), moss (MRS), and moss + O. hainanensis (MORS)], and root [O. hainanensis (OHR), moss (MR), and moss + O. hainanensis (MOR)] using metagenomics sequencing across dry and wet seasons in limestone habitats on Hainan Island. During the dry season, combined plant samples MOR, MO, and MORS showed higher nutrients, supported by microbes that enhance nutrient turnover, which may indicate facilitation. Conversely, during the wet season, increased moisture leads to decreased nutrient levels and microbial communities shift, associated with slower nutrient turnover in combined plant samples, which may reflect competition. According to KEGG analysis, an increase in oxidative phosphorylation and ABC transporters in the dry season supported the facilitative interaction, while quorum sensing and two-component systems supported the competitive interaction in the wet season. These findings show how shifts between facilitation and competition arise from seasonal conditions and microbes in the limestone ecosystem. Full article

Due to limited land resources and traditional farming practices, continuous cassava cropping is common in China. This practice leads to soil degradation, including reduced fertility, imbalanced microbial communities, and lower crop yields. In this study, we investigated the impacts of continuous cassava cropping (CC) and cassava–maize rotation (RC) systems on soil physicochemical properties, microbial community composition, and functional gene abundance related to carbon and nitrogen cycling. The RC system consists of a five-year rotation cycle: cassava is planted in the first year, followed by two consecutive years of maize, and then, cassava is planted again in the last two years. The soil type is classified as Haplic Acrisols with a clay loam texture in this research. Soil samples from both cropping systems were analyzed for physicochemical properties and enzyme activities, and the results showed significant decreases in soil pH, available nitrogen, available phosphorus, and available potassium in CC. Using metagenomic sequencing, 1,280,928 and 1,224,958 unigenes were identified under RC and CC, respectively, with differences in microbial taxonomic and functional profiles. Bacteria accounted for 89.257% of the soil community in RC, whereas the proportion was 88.72% in CC. The proportions of eukaryota and viruses in RC were 0.031% and 0.006%, respectively; in contrast, their proportions were 0.04% and 0.02% in CC, respectively. Cassava–maize rotation promoted the metabolic activities of soil microbes, leading to a significant enhancement in functional genes related to nitrogen and carbon cycling, such as nasA, nasD, nrtC, coxA, porA, and frdA. This shows that microbial activity and nutrient cycling improved in the crop rotation system. Thus, these findings highlight the importance of crop rotation for maintaining soil health, enhancing microbial functions, and improving sustainable cassava production. This study provides valuable insights into the management of cassava agroecosystems and the mitigation of the adverse effects of continuous cropping. Full article

Background: Lespedeza davurica is an important perennial leguminous shrub endemic to China’s Loess Plateau, and it plays a crucial role in ecosystem restoration and soil erosion control. However, phosphorus deficiency and environmental stresses limit its growth potential and ecological function. Methods: In the present study, the interaction between Acinetobacter calcoaceticus DP25, a phosphate-solubilizing rhizobacterium isolated from L. davurica rhizosphere, and L. davurica was investigated. We performed biochemical analyses of leaves from L. davurica planted in saline–alkali soil to monitor antioxidant defense systems and stress-related metabolites, and conducted a combination of transcriptomics and metabolomics approaches to elucidate the bacteria-mediated enhancement of growth and stress tolerance in L. davurica. Results: DP25 inoculation substantially enhanced L. davurica growth performance, increasing plant height by 47.68%, biomass production by 102.54–132.42%, and root architecture parameters by 62.68–78.79% (p < 0.0001). Catalase activity, a key antioxidant enzyme, showed a marked increase of 41.53% (p < 0.001), while malondialdehyde and free proline contents decreased by 18.13% and 19.33%, respectively (p < 0.05). Transcriptomic analysis revealed 263 differentially expressed genes, with enrichment in carotenoid biosynthesis, ABC transporters, and pentose and glucuronate interconversion pathways. Metabolomic profiling identified 246 differentially accumulated metabolites, highlighting enhanced secondary metabolite production and stress response mechanisms. Integration of multi-omics data revealed 19 co-regulated pathways involved in growth promotion and stress tolerance. Conclusions: A. calcoaceticus DP25 enhances L. davurica growth through coordinated regulation of metabolic pathways involved in photosynthesis, antioxidant defense, and secondary metabolite biosynthesis. These findings provide molecular insights into beneficial plant–microbe interactions and support the development of sustainable strategies for ecosystem restoration in degraded environments. Full article

Plants are constantly exposed to various environmental challenges, such as drought, flooding, heavy metal toxicity, and pathogen attacks. To cope with these stresses, they employ several adaptive strategies. This review highlights the potential of plant-derived smoke (PDS) solution as a natural biostimulant for improving plant health and resilience, contributing to both crop productivity and ecological restoration under abiotic and biotic stress conditions. Mitigating effects of PDS solution against various stresses were observed at morphological, physiological, and molecular levels in plants. PDS solution application involves strengthening the cell membrane by minimizing electrolyte leakage, which enhances cell membrane stability and stomatal conductance. The increased reactive-oxygen species were managed by the activation of the antioxidant system including ascorbate peroxidase, superoxide dismutase, and catalase to meet oxidative damage caused by challenging conditions imposed by flooding, drought, and heavy metal stress. PDS solution along with other by-products of fire, such as charred organic matter and ash, can enrich the soil by slightly increasing its pH and improving nutrient availability. Additionally, some studies indicated that PDS solution may influence phytohormonal pathways, particularly auxins and gibberellic acids, which can contribute to root development and enhance symbiotic interactions with soil microbes, including mycorrhizal fungi. These combined effects may support overall plant growth, though the extent of PDS contribution may vary depending on species and environmental conditions. This boost in plant growth contributes to protecting the plants against pathogens, which shows the role of PDS in enduring biotic stress. Collectively, PDS solution mitigates stress tolerance in plants via multifaceted changes, including the regulation of physico-chemical responses, enhancement of the antioxidant system, modulation of heavy metal speciation, and key adjustments of photosynthesis, respiration, cell membrane transport, and the antioxidant system at genomic/proteomic levels. This review focuses on the role of PDS solution in fortifying plants against environmental stresses. It is suggested that PDS solution, which already has been determined to be a biostimulant, has potential for the revival of plant growth and soil ecosystem under abiotic and biotic stresses. Full article

Desert ecosystems pose extreme challenges to plant survival. This study explores the adaptive strategies of two xerophytic halophytes, Alhagi sparsifolia and Nitraria roborowskii, in Xinjiang’s Ebinur Lake wetland, focusing on their plant–soil–microbe (PSM) coupling systems across desert gradients. Results revealed significant interspecific and gradient-dependent differences in plant functional traits: A. sparsifolia showed high growth plasticity with a fast-growth strategy, while N. roborowskii adopted a conservative strategy. Rhizosphere soil physicochemical properties and microbial community structure exhibited strong spatial heterogeneity and host specificity, with N. roborowskii having a more complex microbial network and A. sparsifolia showing higher modularity. Multivariate factor analysis elucidated couplings among plant traits, soil properties, enzymes, and microbes. The two species form distinct interaction systems adapted to desert saline–alkali stress, advancing the understanding of ecological adaptation and informing restoration. Full article

The current proceedings summarize the presentations delivered during the third International Electronic Conference on Microbiology (ECM 2025), which was held online from 1 to 3 April 2025, via the SciForum platform. This virtual event brought together researchers from around the world to share recent advances in microbiological sciences. The ECM 2025 highlighted recent developments across a broad spectrum of microbiological research, including antimicrobial resistance, gut microbiota, infectious diseases, and environmental microbiomes. Participants shared their work through online presentations and abstracts, with selected submissions invited for full publication. The event fostered global collaboration, promoted open-access science, and showcased innovative tools for studying and managing microbial systems in health, agriculture, and industry. The multidisciplinary program was organized into several thematic sessions: S1. Gut Microbiota and Health Disease. S2. Foodborne Pathogens and Food Safety. S3. Antimicrobial Agents and Resistance. S4. Emerging Infectious Diseases. S5. Microbiome and Soil Science. S6. Microbial Characterization and Bioprocess. S7. Microbe–Plant Interactions. This conference report presents summaries of the contributions made by participating authors over the three-day event. Full article