Search Results (559)

Northern corn leaf blight (NCLB), caused by Exserohilum turcicum, is a major foliar disease of maize worldwide. To develop sustainable alternatives that reduce chemical products, we evaluated Bacillus velezensis EM-A8 (GenBank accession number OL704805) as a biocontrol agent under greenhouse and field conditions. The aims of this study were as follows: (i) characterize phytohormone production in two formulations containing the BCA; (ii) assess the influence of the BCA on plant biomass and yield; (iii) compare the efficacy of both formulations in controlling NCLB under field conditions; and (iv) determine whether the treatments affected salicylic acid and phenolic compound levels in maize tissues. The strain synthesized a broad spectrum of phytohormones, including salicylic acid, indoleacetic acid, indolebutyric acid, jasmonic acid, abscisic acid and gibberellic acid, as well as cytokinins such as kinetin, zeatin, and 6-benzylaminopurine. Foliar application increased maize dry biomass by 30%. In field trials, both formulations effectively suppressed NCLB, reducing the number of symptomatic leaves by 25–50% compared with controls. Furthermore, treated plants exhibited yield increases exceeding 1000 kg/ha. These findings demonstrate that B. velezensis EM-A8 provides effective biocontrol of E. turcicum while simultaneously enhancing maize growth and yield under field conditions. Future work should aim to scale up the use of B. velezensis EM-A8 in integrated pest management programs and evaluate its long-term impact on soil microbiota, plant health, and yield sustainability. Full article

The microbial communities of desert-dwelling reptiles, such as lizards, are vital for their health and adaptation, yet remain poorly understood. This study provides the first detailed analysis of the microbiome of the Turpan Wonder Gecko (Teratoscincus roborowskii), using 16S rRNA sequencing on samples from its gut, oral cavity and environment in China’s Turpan Depression. The results showed distinct microbial profiles across these niches. Key findings include a highly diverse gut microbiota, primarily belonging to the phyla Bacteroidota and Bacillota, as well as thermophilic Thermodesulfobacteriota, which may enhance heat tolerance. The oral microbiota was rich in Pseudomonadota, likely aiding its omnivorous diet. Environmental samples were mostly Cyanobacteriota, typical of desert soils. Gut microbes appear to be specialized in carbohydrate metabolism, while oral microbes may assist in xenobiotic degradation. These results emphasize the important role that the gecko’s microbial communities play in its survival in harsh desert conditions. Full article

Coal-derived soil amendments have been shown to improve soil physicochemical properties and promote plant growth; however, their effects on rhizosphere microbial communities remain insufficiently understood. In this study, a comprehensive assessment of the impacts of a lignite coal-based, microbially processed amendment on lettuce (Lactuca sativa) growth, soil properties, and rhizosphere microbiota was conducted. Application of the coal-based amendment resulted in a more than two-fold increase in plant fresh weight compared to untreated soil. The amendment significantly improved soil organic matter content but did not increase phosphate or potassium levels. Rhizosphere bacterial and fungal communities were profiled using 16S rRNA and ITS gene sequencing. Principal coordinate analysis revealed that the coal-based amendment, commercial organic fertilizer, and raw coal each induced distinct shifts in microbial community structure. Notably, treatment with the coal-based amendment reduced the relative abundance of Proteobacteria while increasing Acidobacteriota and Chloroflexi in the bacterial community. In fungal communities, the amendment decreased Basidiomycota and enriched Ascomycota. These results suggest that the observed enhancement in plant growth is closely linked to changes in rhizosphere microbial composition and soil organic matter content, highlighting the potential of microbially processed coal products as sustainable soil amendments in agriculture. Full article

This study explored the potential of bacterial consortia to remediate real diesel-contaminated agricultural soils. Two consortia were tested: a native consortium isolated from contaminated soil and an exogenous consortium derived from vermicompost. Bacterial communities (consortia and soils) were characterized through high-throughput sequencing. Within 30 days, total petroleum hydrocarbons (TPH) were removed most efficiently by bioaugmentation with the native consortium (53.32%), followed by the exogenous vermicompost consortium (47.14%) and the indigenous microbiota (42.52%). Gas chromatography confirmed the reduction of polycyclic aromatic hydrocarbons (PAHs) with 2–5 rings; however, terphenyl, chrysene, and pyrene persisted. The highest TPH biodegradation rate was observed in the treatment inoculated with the native consortium (208.5 mg/kg per day), followed by the treatment with indigenous microbiota (181.8 mg/kg per day) and the exogenous consortium (161.9 mg/kg per day). Furthermore, hydrocarbon-degrading bacterial populations increased significantly during the first week but declined after day 21, showing a negative correlation with TPH concentrations across all treatments, indicating that the highest bacterial activity and degradation occurred during the first 14 days. Taxonomic analysis identified Actinobacteria as the most abundant phylum in the initial soil, whereas Proteobacteria dominated both the consortia and the bioremediated soils. Significant differences in community structure and composition were observed between the consortia according to their origin, influencing removal efficiency. Dominant genera shifted from Nocardioides and Streptomyces in untreated soil to Pseudomonas, Sphingobium, and Pseudoxanthomonas following biological treatments, while Nocardia, Rhodococcus, and Bacillus remained nearly constant. These findings underscore the effectiveness of adapted bacterial consortia in restoring real diesel-contaminated agricultural soils and highlight potential microbial succession patterns associated with biodegradation and soil ecological recovery. Full article

Soil-borne plant pathogens pose a serious threat to global food security by causing extensive yield losses and compromising crop quality. Conventional chemical-based control methods often prove inadequate, environmentally harmful, and disruptive to beneficial soil microbiota, highlighting the urgent need for sustainable alternatives. Plant growth-promoting fungi (PGPF) have emerged as effective biocontrol agents capable of suppressing diverse soil-borne pathogens while simultaneously enhancing plant growth and resilience. This review synthesizes current knowledge on the tripartite interactions among plants, pathogens, and PGPF within the rhizosphere, with emphasis on their roles in disease suppression, rhizosphere competence, and plant health promotion. The findings highlight that PGPF such as Trichoderma, Penicillium, Aspergillus, non-pathogenic Fusarium, hypovirulent binucleate Rhizoctonia and sterile fungi can significantly reduce diseases caused by fungi, oomycetes, bacteria, nematodes, and protists through mechanisms including antibiosis, hyperparasitism, competition, and induction of systemic resistance. Evidence also indicates that consortium approaches and bioformulations enhance field efficacy compared to single-strain applications. Despite this progress, challenges such as variability in field performance, limited shelf life of inoculants, and gaps in understanding ecological interactions constrain large-scale use. Overall, the review underscores that PGPF-based strategies represent a promising and sustainable alternative to chemical pesticides, with strong potential for integration into holistic crop disease management under changing climatic conditions. Full article

The role of the rhizosphere microbiome in naturally suppressing soilborne diseases remains a critical unknown in sustainable agriculture. We investigated this by challenging three genotypes of tomato plants grown in pre-sterilized and natural soils with three major soil-borne pathogens: Ralstonia solanacearum, Fusarium oxysporum f. sp. lycopersici, and Meloidogyne incognita. The results showed that all tomato genotypes grown in pre-sterilized soils exhibited significantly higher disease severity with all pathogens. This protective effect was linked to higher microbial diversity and the abundance of beneficial taxa like Sphingomonas and Mortierella in natural soil as a significant reduction was recorded in microbial diversity and these microbial taxa in pre-sterilized soil. Pre-sterilization shifted community assembly from deterministic processes to stochastic processes, reducing functional stability. Functional predictions further demonstrated an enrichment of growth-promoting and disease-suppressive traits in natural soils, while sterilized soils favored pathogen-associated functions. Co-occurrence network analysis confirmed that the natural microbiome formed a more complex and robust microbial network, likely increasing its resistance to pathogen invasion. Notably, the reintroduction of soil microbiota from healthy plants partially restored tomato resistance to the three pathogens. These findings highlight the key role of stable rhizosphere microbial communities in suppressing soil-borne diseases and emphasize the importance of conserving microbial diversity and functional stability for plant health and sustainable agriculture. Full article

The partial substitution of chemical fertilizer with organic fertilizer has been regarded as an effective strategy for enhancing crop yield and soil quality. Nevertheless, its effects on soil properties and microbes remain contentious. In this study, we examined the effects of four different fertilization strategies (including without fertilizer (CK), 100% chemical fertilizer (NPK), 30% organic fertilizer + 70% chemical fertilizer (LOM) and 60% organic fertilizer + 40% chemical fertilizer (HOM)) on soil nutrients and microbial communities through metagenomic sequencing in a Camellia oleifera field experiment. Compared to CK and NPK, HOM significantly increased SOC, TN, TP, AK and AN contents. The substitution of organic fertilizer notably increased Camellia oleifera yield, with the highest increase of 93.35% observed in HOM relative to NPK. Soil bacterial and fungal communities responded inconsistently to fertilization patterns. Bacteria predominated as the main soil microorganisms, and higher rates of organic fertilizer substitution facilitated a shift from bacterial to fungal communities. Organic fertilizer substitution significantly increased soil bacteria diversity and fungal richness, particularly in the HOM. Soil bacterial community structure was more sensitive to fertilization regimes than soil fungi. High rates of organic fertilizer substitution substantially suppressed oligotrophic and increased copiotrophic bacterial communities. Mucoromycota emerged as the dominant fungal group, with a considerable increment in HOM soils. SOC and TN were the main factors affecting Camellia oleifera yield and shaping soil bacteria and fungal diversity and composition. This study provided crucial insights into the ecological implications of organic fertilizer application and the potential of managing soil microorganisms for sustainable Camellia oleifera productivity. Full article

Background: The accumulation of glycosidic polymers in Lilium brownii var. viridulum Baker (Lv) bulbs fundamentally governs the nutritional and medicinal properties. Methods: In this study, metabolomic, transcriptomic, and microbiome analyses were integrated to elucidate the differential mechanisms of glycoside accumulation between the elite ‘Xuefeng’ (Lv, X) and ‘Longya’ (Lv, L), each comprising three biological replicates. Results: The results demonstrate significantly elevated diversity and abundance of glycosides in X bulbs, with glucose derivatives constituting the predominant fraction. Differential expression genes (DEGs) associated with carbohydrate metabolism were primarily enriched in starch/sucrose metabolism and amino sugar metabolic pathways. Planctomycetes in rhizospheric soil, combined with Acidobacteriia and Rhodanobacteraceae in non-rhizospheric soil, were identified as key microbial taxa associated with glycoside accumulation. Variation partitioning analysis (VPA) revealed that synergistic genetic microbiota–host interactions collectively accounted for 86.8% of the metabolic variance. Conclusions: Consequently, X exhibits superior potential as a medicinal/edible cultivar and as a breeding material due to its enhanced biosynthesis of glycosidic polymers. This work, for the first time, systematically deciphers the regulatory framework of glycoside accumulation in Lv bulbs, highlighting microbiota–host synergy, and provides critical insights for the refining of biosynthetic pathways and targeted crop enhancement. Full article

Silver nanoparticles (AgNPs) synthesized by ‘green’ methods using plant extracts have emerged as promising antimicrobial agents for combating soilborne pathogens. In this study, the antimicrobial activity of four AgNP formulations prepared using various reducing agents (AgNP#1, AgNP#2, AgNP#3, AgNP#4) against sanitary-indicator bacteria (Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29213, Staphylococcus aureus ATCC 25923, Pseudomonas aeruginosa ATCC 27853) and phytopathogenic Pseudomonas syringae strains isolated from Zea mays plants was estimated. The results demonstrated that AgNP#3 and AgNP#4 exhibited the greatest antibacterial efficacy, with minimal inhibitory concentrations (MIC). The soil incubation studies confirmed that AgNPs reduced the population of P. syringae without significant effects on beneficial soil microbiota. AgNP#1 and AgNP#2 exhibited a stimulatory effect on the Zea mays seed germination, bringing out their potential for agricultural applications. Thus, the developed biogenic AgNPs could serve as efficient antimicrobial agents for sustainable soil sanitation while minimizing environmental risks. Full article

Soil-borne diseases of banana severely threaten the sustainable development of the banana industry. In the pineapple–banana rotation system, using rhizosphere microorganisms to control banana Fusarium wilt via pineapple root exudates is a promising green control strategy. However, the role of volatile organic compounds (VOCs) in mediating disease suppression remains unclear. To explore the disease-inhibiting mechanisms, this study employed in vitro assays and high-throughput sequencing to evaluate the effects of three pineapple-root-derived VOCs (decanal, nonanal, octanol). The results showed the following: (1) All three VOCs strongly inhibited the mycelial growth of Fusarium, with octanol exhibiting the highest inhibition. (2) Each VOC promoted Arabidopsis thaliana growth, and decanal was the most effective. (3) In pot experiments, these VOCs significantly altered the banana rhizosphere microbial community, facilitating the colonization of beneficial genera—characterized by reduced microbial diversity and increased beneficial genera abundance. These results delineate a VOC-mediated rhizosphere microbe–Fusarium–plant interaction network, offering a novel theoretical foundation for the ecological control of banana diseases via the rhizosphere microbiome. In conclusion, this study elucidates a new mechanism for banana disease inhibition via VOCs, highlighting the positive impacts on plant growth and rhizosphere soil health through microbiota modulation. Full article

Aflatoxins (AFs) and fumonisins (FUMs) are among the most prevalent and toxic mycotoxins affecting maize production globally. In Mexico, their co-occurrence poses a significant public health concern, as maize is not only a dietary staple but also predominantly grown and consumed at the household level. This review examines the multifactorial nature of AFs and FUMs contamination in Mexican maize systems, considering the roles of maize germplasm, agricultural practices, environmental conditions, and soil microbiota. Maize landraces, well-adapted to diverse agroecological zones, exhibit potential resistance to AFs contamination and should be prioritized in breeding programs. Sustainable agricultural practices and biocontrol strategies, including the use of atoxigenic Aspergillus flavus strains, are presented as promising interventions. Environmental factors and soil characteristics further influence fungal proliferation and mycotoxin biosynthesis. Advances in microbiome engineering, biological breeding approaches, and predictive modeling offer novel opportunities for prevention and control. The synergistic toxicity of AFs and FUMs significantly increases health risks, particularly for liver cancer, highlighting the urgency of integrated mitigation strategies. While Mexico has regulatory limits for AFs, the lack of legal thresholds for FUMs remains a critical gap in food safety legislation. This comprehensive review underscores the need for biomarker-based exposure assessments and coordinated national policies, alongside multidisciplinary strategies to reduce mycotoxin exposure and enhance food safety in maize systems. Full article

Water scarcity poses a critical constraint to sustainable agriculture, particularly in small-scale systems that rely on traditional irrigation methods. Although organic matter (OM) is known to enhance soil structure and water-holding capacity, quantitative evidence regarding optimal OM levels and their interaction with microbial activity in agroecological contexts remains limited. This study evaluates the effect of different OM contents (2.37%, 3.42%, 5.55%, 7.89%, and 9.43%) on infiltration, moisture retention, and microbiological dynamics in 129 agroecological plots located in the northern highlands of Ecuador. Field and laboratory assessments revealed that intermediate OM levels (between 3.42% and 5.55%) optimize available water retention (up to 14.78%) and stabilize infiltration. In contrast, excessive OM levels (>7.9%) decrease retention efficiency and increase leaching risk. Microbial activity showed a positive correlation with OM up to a certain threshold, beyond which fungal and yeast activity declined under field conditions. The results underscore the importance of managing OM within an optimal functional range to improve irrigation efficiency, enhance microbial resilience, and support water sustainability in agroecological production systems. Full article

The microbiota associated with Vanilla planifolia grown in three production systems in Puebla, México, was evaluated: shade cloth, cocuite, and acahual. Rhizosphere and soil samples were analyzed, from which bacteria, fungi, yeasts, and actinomycetes were isolated. The bacterial and actinomycete isolates were characterized morphologically and biochemically, and their potential as growth promoters was evaluated. Morphological and microscopic characteristics identified the fungi. In parallel, agronomic variables were measured in five plants per system, and the data were analyzed using ANOVA and Tukey’s test (p ≤ 0.05). The results showed that the shade cloth favored a greater number of internodes, total leaves, and biomass, although with a higher incidence of diseased leaves. The cocuite presented intermediate values, while the acahual had lower leaf density but fewer leaf health problems. Microbial composition varied across systems, with potentially beneficial bacteria and actinomycetes, as well as both beneficial and pathogenic fungi, being prominent. These findings demonstrate the influence of the management system on the microbiota and health of V. planifolia, providing a basis for more sustainable production strategies for vanilla cultivation in Mexico. Full article

Microalgae and cyanobacteria, as versatile photoautotrophic microorganisms, hold significant promise for mitigating soil and water pollution—particularly the removal of pesticides. This review examines their multifaceted roles in pesticide biodegradation, emphasizing how their metabolic capabilities simultaneously reduce environmental toxicity, enrich soil properties, and support beneficial microbiota. Cultivation in wastewater treatment systems further highlights their potential for cost-effective bioremediation, as these microbes degrade pesticides, recycle nutrients, break down organic pollutants, and generate biomass with value-added applications. Despite these advantages, implementing large-scale processes remains challenging. Key hurdles include optimizing growth parameters, preventing contamination, improving harvest efficiency, and designing robust bioreactors. Addressing these complexities demands interdisciplinary collaboration in strain selection, metabolic engineering, and process intensification. By capitalizing on microalgae and cyanobacteria’s adaptability and metabolic flexibility, we can develop more sustainable management strategies that reduce reliance on chemical inputs, foster soil health, and contribute to long-term ecological restoration. Ultimately, these microorganisms have the potential to reshape environmental stewardship by combining economic viability with broad-scale ecological benefits. Full article

With the rapid expansion of industrial activities, the accumulation of heavy metals in the environment has become a serious threat to ecological security and public health. Rhizosphere microorganisms play a crucial role in supporting the growth and quality of medicinal plants by facilitating nutrient uptake and regulating hormonal balance. However, medicinal plants can absorb heavy metals from contaminated soils during growth, resulting in toxic metal accumulation in plant tissues and reduced efficacy of active compounds. At the same time, excessive heavy metal levels suppress rhizosphere microbial growth and activity, disrupt community structure and function, and weaken their beneficial interactions with plants. These processes collectively lead to soil fertility decline, hindered plant development, and compromised safety and quality of medicinal materials. This review systematically summarizes the mechanisms by which heavy metals affect medicinal plants and their rhizosphere microbiota, and highlights that future research should focus on elucidating these interactions, developing advanced remediation technologies, and establishing comprehensive monitoring systems for the quality and safety of medicinal plants, thereby providing a scientific basis for their safe utilization and quality improvement. Full article