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Methazolamide is an important carbonic anhydrase inhibitor and is mainly used for the treatment of glaucoma. Studies are extremely rare regarding the impurities in methazolamide products. In this work, the high‐performance liquid chromatography/high‐performance liquid chromatography‐mass spectrometry methods were established for the analysis of impurities in methazolamide products. Five impurities (A, B, C, D, and E) were detected using the established high‐performance liquid chromatography/high‐performance liquid chromatography‐mass spectrometry methods. Of these impurities, impurities A, B, and D are known compounds, and impurities C and E are novel compounds that have never been reported before. The identities of impurities A, B, D, and E were recognized by comparing their retention times and mass spectra with those of synthesized standard compounds under the same high‐performance liquid chromatography‐mass spectrometry conditions. Moreover, the structures of impurities C and E were characterized using a variety of analytical techniques including multidimensional nuclear magnetic resonance spectroscopy, Fourier transforming infrared spectroscopy, ultraviolet‐visible absorption spectroscopy, and high‐resolution quadrupole time‐of‐flight mass spectrometry. All of the five impurities are structural analogs of methazolamide. The formation mechanisms of these impurities were discussed. [ABSTRACT FROM AUTHOR]

Soil microbial carbon use efficiency (CUE) is a crucial parameter that can be used to evaluate the partitioning of soil carbon (C) between microbial growth and respiration. However, general patterns of microbial CUE among terrestrial ecosystems (e.g., farmland, grassland, and forest) remain controversial. To address this knowledge gap, data from 41 study sites (n = 197 soil samples) including 58 farmlands, 95 forests, and 44 grasslands were collected and analyzed to estimate microbial CUEs using a biogeochemical equilibrium model. We also evaluated the metabolic limitations of microbial growth using an enzyme vector model and the drivers of CUE across different ecosystems. The CUEs obtained from soils of farmland, forest, and grassland ecosystems were significantly different with means of 0.39, 0.33, and 0.42, respectively, illustrating that grassland soils exhibited higher microbial C sequestration potentials (p <.05). Microbial metabolic limitations were also distinct in these ecosystems, and carbon limitation was dominant exhibiting strong negative effects on CUE. Exoenzyme stoichiometry played a greater role in impacting CUE values than soil elemental stoichiometry within each ecosystem. Specifically, soil exoenzymatic ratios of C:phosphorus (P) acquisition activities (EEAC:P) and the exoenzymatic ratio of C:nitrogen (N) acquisition activities (EEAC:N) imparted strong negative effects on soil microbial CUE in grassland and forest ecosystems, respectively. But in farmland soils, EEAC:P exhibited greater positive effects, showing that resource constraints could regulate microbial resource allocation with discriminating patterns across terrestrial ecosystems. Furthermore, mean annual temperature (MAT) rather than mean annual precipitation (MAP) was a critical climate factor affecting CUE, and soil pH as a major factor remained positive to drive the changes in microbial CUE within ecosystems. This research illustrates a conceptual framework of microbial CUEs in terrestrial ecosystems and provides the theoretical evidence to improve soil microbial C sequestration capacity in response to global change. [ABSTRACT FROM AUTHOR]

Abstract: Neriifolone B (1), a natural product containing a novel 4′,4′-dimethyl-4′,5′-dihydropyran-6-one[2′,3′:3,4]xanthone skeleton, was found to be a potent inhibitor of transcription mediated by retinoid X receptor α (RXRα). The first total synthesis of neriifolone B (1) was achieved in 14 steps with an overall yield of 7.1%. A Claisen rearrangement was employed as the key step in the sequence. The activity of six natural xanthones and eight compounds related to neriifolone B (1) against RXRα-mediated transcription was evaluated. Two neriifolone B analogs, 17 and 11″, were potent inhibitors of RXRα transcriptional activity. Preliminary structure–activity relationship studies are discussed briefly. [Copyright &y& Elsevier]

While the properties of biochar are closely related to its functional groups, it is unclear under what conditions biochar develops its properties. In this study, two-dimensional (2D) 13C nuclear magnetic resonance (NMR) correlation spectroscopy was for the first time applied to investigate the development of functional groups and establish their relationship with biochar properties. The results showed that the agricultural biomass carbonized to biochars was a dehydroxylation/dehydrogenation and aromatization process, mainly involving the cleavage of O-alkylated carbons and anomeric O-C-O carbons in addition to the production of fused-ring aromatic structures and aromatic C-O groups. With increasing charring temperature, the mass cleavage of O-alkylated groups and anomeric O-C-O carbons occurred prior to the production of fused-ring aromatic structures. The regression analysis between functional groups and biochar properties (pH and electrical conductivity) further demonstrated that the pH and electrical conductivity of rice straw derived biochars were mainly determined by fused-ring aromatic structures and anomeric O-C-O carbons, but the pH of rice bran derived biochars was determined by both fused-ring aromatic structures and aliphatic O-alkylated (HCOH) carbons. In summary, this work suggests a novel tool for characterising the development of functional groups in biochars. [ABSTRACT FROM AUTHOR]

Aims: Potato bacterial wilt ( Ralstonia solanacearum) is a soil-borne disease that affects the potato plant ( Solanum tuberosum) worldwide and causes serious economic losses in southern China. The objective of this study is to study the effect of bacterial antagonists and bio-organic fertilizers on potato bacterial wilt and rhizosphere soil microbial population. Methods: In the present study, pot and field experiments were conducted to evaluate the LH23 ( Bacillus amyloliquefaciens) and LH36 ( Bacillus subtilis) strains and their derived bio-organic fertilizers (BIO23 and BIO36) as potential biocontrol agents against potato bacterial wilt. Results: BIO23 and BIO36 decreased the incidence of bacterial wilt disease and increased potato yields. In pot experiments, the disease incidence of BIO23 and BIO36 was 8.9 % and 11.1 % respectively, much lower than the control (57.7 %). The biocontrol efficiency of BIO23 was 84.6 %, which was the most successful treatment and BIO36 was the second with a biocontrol efficiency of 80.8 %. The increased percentages of potato yields when compared with the control were 63.5 % (BIO23), 64.7 % (BIO36) 34.8 % (LH23), 33.6 % (LH36) and 20.7 % (OF). The counts of antagonists, bacteria and actinobacteria in the rhizosphere soil were significantly increased in BIO23 and BIO36 treatments, whereas the counts of R. solanacearum and fungi in the soil in the both treatments decreased. In field experiments, 70 days after treatment, the biocontrol efficacies of BIO23 and BIO36 treatments were 92.0 % and 84.0 %, and the yield increases of BIO23 and BIO36 treatments were 42.3 % and 28.8 %, respectively, when compared with the organic fertilizer treatment. In addition, the changes in the microbial populations were the same as those observed in the greenhouse experiment. Conclusions: Potato bacterial wilt could be well controlled by the application bio-organic fertilizer containing a specific antagonist, mainly through the alternation of soil microbial community [ABSTRACT FROM AUTHOR]

To relate the characteristics of root architecture and the kinetic parameters of nitrate (NO3) uptake, two typical lettuce cultivars (Lactuca sativa L.), ‘Sx1’ and ‘Nrnct’, were exposed to different nutrient solutions: 100% NO3-N (T1), 10% ammonium (NH4)-N + 90% NO3-N (T2), 10% NH4-N + 100% NO3-N (T3). The results obtained indicate that total root surface area, root volume, total root length and root number increased with the increased of NH4-N; the NH4-N in the nutrient solution had significant effects on the rates of NO− 3 uptake, Vmax of NO− 3 uptake kinetics in T1 was significantly higher than with T2 and T3, Km of NO− 3 uptake kinetics in T1 was lower than that of T2 and T3, but the difference was not significant, NH4-N inhibited NO− 3 uptake mainly due to the higher Vmax. Based on the NO− 3 uptake rate, NO− 3 content, Vmax and Km, the different cultivars differed in their nitrate uptake characteristics. [ABSTRACT FROM PUBLISHER]

Laboratory tests and greenhouse experiments were carried out to investigate the abilities of Bacillus subtilis Y-IVI to promote plant growth and to colonize the rhizosphere and interior tissues of muskmelon. Laboratory tests showed that B. subtilis Y-IVI can produce indole acetic acid, siderophores, and ammonia. The inoculation of soil with green fluorescent protein-tagged Y-IVI (GY-IVI) significantly increased plant shoot and root dry weights as compared with the non-inoculated soils. The inoculation of soil with B. subtilis GY-IVI maintained approximately 10 colony-forming units (cfu) of GY-IVI per gram of dry rhizosphere soil for 1 month. The GY-IVI recovered from the interior of crowns and roots in the inoculated soil were 10 and 10 cfu g dry weight, respectively, suggesting that GY-IVI acted as an endophyte. In the present study, we combined the two important growth promotion ingredients, colonization ability and growth promotion metabolites produced by biological agents, to investigate B. subtilis Y-IVI's promotion effects on muskmelon growth. [ABSTRACT FROM AUTHOR]

This review focuses on plant acquisition and transport of the inorganic forms of nitrogen, phosphorus and sulfur. Families of membrane transporters have been identified and several members are well characterised. Although some families are large, specific members may be expressed in a particular membrane or cell type, or at certain times during development. Therefore, each transporter can have specific activities and the concept of functional redundancy is questionable. Structurally related proteins can mediate all transport steps within the plant, including uptake from the soil. Although transport mechanisms and membrane locations may be different, a picture is emerging that suggests sequence homology can be a reasonable indicator of the nutrient that is transported by each protein. [Copyright &y& Elsevier]

Pot experiments were conducted in a glasshouse to investigate the effect of soil water content and phosphorus (P) supply on biomass, P uptake by rice cultivated in soils with different water regimes and soil available P. Results showed that P application rates had greater effect on P nutrition of rice than soil moisture content. Yield of rice grain was significantly decreased when soil moisture content was kept at 60% of water holding capacity (WHC) while the yields of rice grain were not significantly different when soil moistures were remained at 80% of WHC and waterlogged. This meant that it was possible for paddy rice variety to be cultivated in aerobic soil under the condition of sufficient P supply. The highest biomass of rice and highest P uptake by rice were found in the treatment with 0.0300 g P kg−1 of P application rate and with 80% of WHC. Soil available P content decreased with the decrease of both the soil moisture content and the P applied. Rice crop exhausted soil P to a great extent leading to very low available soil P content when the rice crop was harvested, especially in the soil receiving no or small amounts of P fertilizer. All the results obtained in this experiment could provide the theoretic base for water and P management of paddy rice variety cultivated in aerobic soil in the southern hilly areas of China. [ABSTRACT FROM AUTHOR]

As an alternative production strategy, the cultivation of rice under upland condition is increasing in the areas where fresh water resource is limited during growing season. The main form of nitrogen (N) taken up by rice roots is shifted from ammonium (NH4) in flooded paddy soil to nitrate () in upland soil. A pot experiment was conducted in order to study the influence of to ratio on the yield and uptake of N by rice (Oryza sativa L.) grown under upland conditions. The sandy-loam soil (85-kg) used to fill each pot was mulched by semi-decomposed straw, and a total 4.8 g N per pot was supplied as a fertilizer topdressing at five ratios of -N/-N (0/100, 25/75, 50/50, 75/25, and 100/0). In comparison to provision of alone, supply of as the only N source produced higher number of effective ears and average weights of 1000 grains, but reduced the grain numbers in each effective ear. The total uptake of N and biomass yield per pot were 2.206 and 182.5 g from applying only , and 2.067 and 163.7 g from -N alone, respectively, while they reached 2.894 and 217.9 g when both forms of N were supplied in equal amounts. Soil -N concentration was constantly maintained at the range of 2–6 mg kg−1 during the vigorous growing period when the supply was less than 75% indicating little risk of N fertilization induced NO3 pollution in the rice-cultivated upland soil. The rice crop did not show a significant preference to the form of or alone. Provision of the dual N sources enhanced the growth and N use efficiency by rice crop cultivated in the upland soil. [ABSTRACT FROM AUTHOR]

Summary: The rhizosphere microbiome plays critical roles in plant growth and provides promising solutions for sustainable agriculture. While the rhizosphere microbiome frequently fluctuates with the soil environment, recent studies have demonstrated that a small proportion of the microbiome is consistently assembled in the rhizosphere of a specific plant genotype regardless of the soil condition, which is determined by host genetics. Based on these breakthroughs, which involved exploiting the plant‐beneficial function of the rhizosphere microbiome, we propose to divide the rhizosphere microbiome into environment‐dominated and plant genetic‐dominated components based on their different assembly mechanisms. Subsequently, two strategies to explore the different rhizosphere microbiome components for agricultural production are suggested, that is, the precise management of the environment‐dominated rhizosphere microbiome by agronomic practices, and the elucidation of the plant genetic basis of the plant genetic‐dominated rhizosphere microbiome for breeding microbiome‐assisted crop varieties. We finally present the major challenges that need to be overcome to implement strategies for modulating these two components of the rhizosphere microbiome. [ABSTRACT FROM AUTHOR]

The effects of companion planting on soil antibiotic resistance genes (ARGs) and associated microbial composition have remained largely unclear until now. In this study, we assessed the changes in the soil microbiome and ARGs frequencies for tomato growing soils that were companion planted with basil (TB) or cilantro (TC) using a metagenome approach. The abundance of the phytopathogen Ralstonia solanacearum was significantly lower in the TC or TB treatments compared to the tomato monoculture soils (TT). A significant enrichment of Pseudomonas and Aquabacterium and a depletion of Nocardioides and Streptomyces were observed in the TC treatment. Interestingly, both TC and TB companion planting reduced the absolute abundance and the number of subtypes of ARGs. The TC soil showed the lowest numbers of unique ARG subtypes, especially the ARGs resistant to vancomycin and rifamycin, as well as those associated with multidrug resistance. Furthermore, network analysis further revealed that Nocardioides and Streptomyces were potential hosts of ARGs, whereas Flavobacterium negatively correlated with mdtG, suggesting a suppressive effect in reducing ARGs. Together, our results suggest that the companion planting of tomatoes with basil or cilantro can reduce the risk of ARG accumulation, making it a feasible farming management tool to promote soil and plant health in sustainable agriculture. [ABSTRACT FROM AUTHOR]

Light as a source of information regulates morphological and physiological processes of fungi, including development, primary and secondary metabolism, or the circadian rhythm. Light signaling in fungi depends on photoreceptors and downstream components that amplify the signal to govern the expression of an array of genes. Here, we investigated the effects of red and far-red light in the mycoparasite Trichoderma guizhouense on its mycoparasitic potential. We show that the invasion strategy of T. guizhouense depends on the attacked species and that red and far-red light increased aerial hyphal growth and led to faster overgrowth or invasion of the colonies. Molecular experiments and transcriptome analyses revealed that red and far-red light are sensed by phytochrome FPH1 and further transmitted by the downstream MAPK HOG pathway and the bZIP transcription factor ATF1. Overexpression of the red- and far-red light-induced fluffy gene fluG in the dark resulted in abundant aerial hyphae formation and thereby improvement of its antagonistic ability against phytopathogenic fungi. Hence, light-induced fluG expression is important for the mycoparasitic interaction. The increased aggressiveness of fluG-overexpressing strains was phenocopied by four random mutants obtained after UV mutagenesis. Therefore, aerial hyphae formation appears to be a trait for the antagonistic potential of T. guizhouense. Author summary: Light controls a large proportion of the genome. While Trichoderma species encode the red-light receptor phytochrome, a detailed study of red-light responses and signaling was lacking. Here, we show that the mycoparasitic fungus Trichoderma guizhouense uses distinct strategies to attack phytopathogenic fungi. It can overgrow or invade the colonies of the attacked species. Red and far-red light promoted aerial hyphal growth and thereby increased both, overgrowth or invasion of the host colonies. The effect required the phytochrome-signaling pathway. We further show that screening for mutants producing more aerial hyphae proves to be an easy way to develop strains with improved biocontrol performance. [ABSTRACT FROM AUTHOR]

While the One Health framework has emphasized the importance of soil microbiomes for plant and human health, one of the most diverse and abundant groups—bacterial viruses, i.e. phages—has been mostly neglected. This perspective reviews the significance of phages for plant health in rhizosphere and explores their ecological and evolutionary impacts on soil ecosystems. We first summarize our current understanding of the diversity and ecological roles of phages in soil microbiomes in terms of nutrient cycling, top-down density regulation, and pathogen suppression. We then consider how phages drive bacterial evolution in soils by promoting horizontal gene transfer, encoding auxiliary metabolic genes that increase host bacterial fitness, and selecting for phage-resistant mutants with altered ecology due to trade-offs with pathogen competitiveness and virulence. Finally, we consider challenges and avenues for phage research in soil ecosystems and how to elucidate the significance of phages for microbial ecology and evolution and soil ecosystem functioning in the future. We conclude that similar to bacteria, phages likely play important roles in connecting different One Health compartments, affecting microbiome diversity and functions in soils. From the applied perspective, phages could offer novel approaches to modulate and optimize microbial and microbe–plant interactions to enhance soil health. [ABSTRACT FROM AUTHOR]

Background: The conversion of plant biomass into biochemicals is a promising way to alleviate energy shortage, which depends on efficient microbial saccharification and cellular metabolism. Trichoderma spp. have plentiful CAZymes systems that can utilize all-components of lignocellulose. Acetylation of polysaccharides causes nanostructure densification and hydrophobicity enhancement, which is an obstacle for glycoside hydrolases to hydrolyze glycosidic bonds. The improvement of deacetylation ability can effectively release the potential for polysaccharide degradation. Results: Ammonium sulfate addition facilitated the deacetylation of xylan by inducing the up-regulation of multiple carbohydrate esterases (CE3/CE4/CE15/CE16) of Trichoderma harzianum. Mainly, the pathway of ammonium-sulfate's cellular assimilates inducing up-regulation of the deacetylase gene (Thce3) was revealed. The intracellular metabolite changes were revealed through metabonomic analysis. Whole genome bisulfite sequencing identified a novel differentially methylated region (DMR) that existed in the ThgsfR2 promoter, and the DMR was closely related to lignocellulolytic response. ThGsfR2 was identified as a negative regulatory factor of Thce3, and methylation in ThgsfR2 promoter released the expression of Thce3. The up-regulation of CEs facilitated the substrate deacetylation. Conclusion: Ammonium sulfate increased the polysaccharide deacetylation capacity by inducing the up-regulation of multiple carbohydrate esterases of T. harzianum, which removed the spatial barrier of the glycosidic bond and improved hydrophilicity, and ultimately increased the accessibility of glycosidic bond to glycoside hydrolases. [ABSTRACT FROM AUTHOR]

Background: Thermotolerance is widely acknowledged as a pivotal factor for fungal survival across diverse habitats. Heat stress induces a cascade of disruptions in various life processes, especially in the acquisition of carbon sources, while the mechanisms by which filamentous fungi adapt to heat stress and maintain carbon sources are still not fully understood. Results: Using Trichoderma guizhouense, a representative beneficial microorganism for plants, we discover that heat stress severely inhibits the lignocellulases secretion, affecting carbon source utilization efficiency. Proteomic results at different temperatures suggest that proteins involved in the poly ADP-ribosylation pathway (TgPARP and TgADPRase) may play pivotal roles in thermal adaptation and lignocellulose utilization. TgPARP is induced by heat stress, while the deletion of Tgparp significantly improves the lignocellulose utilization capacity and lignocellulases secretion in T. guizhouense. Simultaneously, the absence of Tgparp prevents the excessive depletion of ATP and NAD+, enhances the protective role of mitochondrial membrane potential (MMP), and elevates the expression levels of the unfolded protein response (UPR)-related regulatory factor Tgire. Further investigations reveal that a stable MMP can establish energy homeostasis, allocating more ATP within the endoplasmic reticulum (ER) to reduce protein accumulation in the ER, thereby enhancing the lignocellulases secretion in T. guizhouense under heat stress. Conclusions: Overall, these findings underscored the significance of Tgparp as pivotal regulators in lignocellulose utilization under heat stress and provided further insights into the molecular mechanism of filamentous fungi in utilizing lignocellulose. [ABSTRACT FROM AUTHOR]

While temperature has been shown to affect the survival and growth of bacteria and their phage parasites, it is unclear if trade-offs between phage resistance and other bacterial traits depend on the temperature. Here, we experimentally compared the evolution of phage resistance–virulence trade-offs and underlying molecular mechanisms in phytopathogenic Ralstonia solanacearum bacterium at 25 °C and 35 °C temperature environments. We found that while phages reduced R. solanacearum densities relatively more at 25 °C, no difference in the final level of phage resistance was observed between temperature treatments. Instead, small colony variants (SCVs) with increased growth rate and mutations in the quorum-sensing (QS) signaling receptor gene, phcS , evolved in both temperature treatments. Interestingly, SCVs were also phage-resistant and reached higher frequencies in the presence of phages. Evolving phage resistance was costly, resulting in reduced carrying capacity, biofilm formation, and virulence in planta, possibly due to loss of QS-mediated expression of key virulence genes. We also observed mucoid phage-resistant colonies that showed loss of virulence and reduced twitching motility likely due to parallel mutations in prepilin peptidase gene, pilD. Moreover, phage-resistant SCVs from 35 °C-phage treatment had parallel mutations in type II secretion system (T2SS) genes (gspE and gspF). Adsorption assays confirmed the role of pilD as a phage receptor, while no loss of adsorption was found with phcS or T2SS mutants, indicative of other downstream phage resistance mechanisms. Additional transcriptomic analysis revealed upregulation of CBASS and type I restriction-modification phage defense systems in response to phage exposure, which coincided with reduced expression of motility and virulence-associated genes, including pilD and type II and III secretion systems. Together, these results suggest that while phage resistance–virulence trade-offs are not affected by the growth temperature, they could be mediated through both pre- and postinfection phage resistance mechanisms. [ABSTRACT FROM AUTHOR]

The rhizosphere and phyllosphere of plants are home to a diverse range of microorganisms that play pivotal roles in ecosystem services. Consequently, plant growth‐promoting bacteria (PGPB) are extensively utilized as inoculants to enhance plant growth and boost productivity. Despite this, the interactions between the rhizosphere and phyllosphere, which are influenced by PGPB inoculation, have not been thoroughly studied to date. In this study, we inoculated Bacillus velezensis SQR9, a PGPB, into the bulk soil, rhizosphere or phyllosphere, and subsequently examined the bacterial communities in the rhizosphere and phyllosphere using amplicon sequencing. Our results revealed that PGPB inoculation increased its abundance in the corresponding compartment, and all treatments demonstrated plant growth promotion effects. Further analysis of the sequencing data indicated that the presence of PGPB exerted a more significant impact on bacterial communities in both the rhizosphere and phyllosphere than in the inoculation compartment. Notably, the PGPB stimulated similar rhizosphere‐beneficial microbes regardless of the inoculation site. We, therefore, conclude that PGPB can promote plant growth both directly and indirectly through the interaction between the rhizosphere and phyllosphere, leading to the enrichment of beneficial microorganisms. [ABSTRACT FROM AUTHOR]

Background and Aims: Understanding microbial compositions and functions in arable soils is crucial for effective agroecosystem management. While many studies have explored this topic, large-scale investigations are lacking, resulting in the absence of consistent and reliable patterns of communities and functions of soil microorganisms. Methods: To address this gap, we performed an integrated analysis of published sequencing data from the soils of three main arable fields: upland, paddy, and paddy-upland rotation. Results: Bacterial diversity (richness, Shannon) was highest in upland soils. Actinobacteria and Planctomycetes were enriched in upland soils, while Proteobacteria, Chloroflexi, and Nitrospirae preferred paddy and paddy-upland rotation soils. Bacteria in upland soils have a greater functional potential to decompose aromatic compounds, as well as for chitinolysis and ureolysis. Methanotrophy, methylotrophy, sulfur-related respiration, and most nitrogen metabolic processes were enriched in paddy fields. Bacteria in upland soils are characterized by increased dormancy potential and a faster response to resource input than those in paddy and paddy-upland rotation soils. Stochastic processes poorly contribute to the bacterial assembly in paddy soils, indicating strong environmental filtering due to anaerobic conditions. The spatial turnover in bacterial community composition was much faster than the functional potential, indicating high functional redundancy, especially in paddy soils. Edaphic factors were the major contributors to bacterial composition, whereas the cropland type influenced the predicted functions. Conclusions: Land use defines microbial composition, functional attributes, and ecological characteristics (e.g., dormancy potential, assembly processes, and functional redundancy). These findings deepen our knowledge of microbial biogeographic patterns in soils of agricultural ecosystems and provide new insights into sustainable cropland management. [ABSTRACT FROM AUTHOR]

Trichoderma is a widely recognized plant-growth-promoting fungus that has been extensively utilized in various agricultural applications. However, research on the economic production of Trichoderma spores and their effects on tea cuttings must be further advanced. In this study, T. guizhouense NJAU 4742 (NJAU 4742) emerged as a growth-promoting strain for tea cuttings, and the spore-production conditions of NJAU 4742 attained through solid-state fermentation (SSF) using tea residues were optimized. In a pot experiment, nursery substrates containing different concentrations of NJAU 4742 spores were tested for their influence on tea cutting growth and the rhizosphere fungal community. The optimal conditions for spore yield were determined as a 7:3 (w/w) ratio of tea residue to rice bran, a material thickness of 3 cm, an inoculum concentration of 15% (v/w), and an incubation time of 4 days, resulting in a spore count of 1.8 × 109 CFU/g. Applying NJAU 4742 spore products significantly increased the biomass of tea cuttings and influenced the fungal community composition. Moreover, higher concentrations of NJAU 4742 spores yielded better growth performance, and applying nursery substrate with 1.0 × 107 CFU/mL spores was the most economically viable option. Notably, among the top ten fungal genera with the highest relative abundance, Trichoderma showed a positive correlation with the fresh weight of tea cuttings, while the others exhibited a negative correlation. Overall, utilizing tea residue for SSF to produce NJAU 4742 was a feasible approach, and the application of NJAU 4742 spores enhanced the growth of tea cuttings by increasing the relative abundance of Trichoderma. [ABSTRACT FROM AUTHOR]

This document explores the use of synthetic microbial communities (SynComs) to improve soil health and resilience. SynComs are artificial combinations of microorganisms that can enhance soil fertility, pollutant removal, and soil-borne disease suppression. The document emphasizes the importance of microbial interactions and biodiversity in designing efficient SynComs. It also calls for further research to develop more complex SynComs and establish predictive models for soil community structure and ecological function. The authors declare no conflict of interest. [Extracted from the article]

This paper reports on the gas-phase amination reaction of aromatic hydrocarbons occurring under corona discharge conditions with N2 gas as the nitrogen source. The corona discharge device within an atmospheric pressure chemical ionization source was employed to achieve the plasma-assisted N2 fixation, and the coupled ion trap mass spectrometer (IT-MS) was used to detect positively charged product ions. In the model case, under APCI conditions, unusual product ions, [M + 16]+ and [M + 14]+, were observed. Based on the high resolution MS data and tandem mass spectrometric information, [M + 16]+ was confirmed to be protonated p-toluidine and [M + 14]+ was confirmed to be p-methylphenylnitrenium ion. According to the experimental results of the isotopic labelling and substituent effect, one feasible mechanism is proposed as follows. Firstly, N2 is activated by plasma caused via the corona discharge and then electrophilically attacks toluene, yielding the key intermediate, p-methylphenylnitrenium; secondly, the intermediate undergoes double-hydrogen transfer reaction to give rise to the final product ion, protonated p-toluidine. This study may provide a novel idea to explore new and green method for the synthesis of anilines. [ABSTRACT FROM AUTHOR]

Rhizosphere microbes play critical roles for plant's growth and health. Among them, the beneficial rhizobacteria have the potential to be developed as the biofertilizer or bioinoculants for sustaining the agricultural development. The efficient rhizosphere colonization of these rhizobacteria is a prerequisite for exerting their plant beneficial functions, but the colonizing process and underlying mechanisms have not been thoroughly reviewed, especially for the nonsymbiotic beneficial rhizobacteria. This review systematically analyzed the root colonizing process of the nonsymbiotic rhizobacteria and compared it with that of the symbiotic and pathogenic bacteria. This review also highlighted the approaches to improve the root colonization efficiency and proposed to study the rhizobacterial colonization from a holistic perspective of the rhizosphere microbiome under more natural conditions. [ABSTRACT FROM AUTHOR]

Species of the genus Bacillus have been widely used for the biocontrol of plant diseases in the demand for sustainable agricultural development. New mechanisms underlying Bacillus biocontrol activity have been revealed with the development of microbiome and microbe‐plant interaction research. In this review, we first briefly introduce the typical Bacillus biocontrol mechanisms, such as the production of antimicrobial compounds, competition for niches/nutrients, and induction of systemic resistance. Then, we discussed in detail the new mechanisms of pathogen quorum sensing interference and reshaping of the soil microbiota. The "cry for help" mechanism was also introduced, in which plants can release specific signals under pathogen attack to recruit biocontrol Bacillus for root colonization against invasion. Finally, two emerging strategies for enhancing the biocontrol efficacy of Bacillus agents, including the construction of synthetic microbial consortia and the application of rhizosphere‐derived prebiotics, were proposed. [ABSTRACT FROM AUTHOR]

The assembly of bacterial communities in the rhizosphere is well‐documented and plays a crucial role in supporting plant performance. However, we have limited knowledge of how plant rhizosphere determines the assembly of protistan predators and whether the potential associations between protistan predators and bacterial communities shift due to rhizosphere selection. To address this, we examined bacterial and protistan taxa from 443 agricultural soil samples including bulk and rhizosphere soils. Our results presented distinct patterns of bacteria and protistan predators in rhizosphere microbiome assembly. Community assembly of protistan predators was determined by a stochastic process in the rhizosphere and the diversity of protistan predators was reduced in the rhizosphere compared to bulk soils, these may be attributed to the indirect impacts from the altered bacterial communities that showed deterministic process assembly in the rhizosphere. Interestingly, we observed that the plant rhizosphere facilitates more close interrelationships between protistan predators and bacterial communities, which might promote a healthy rhizosphere microbial community for plant growth. Overall, our findings indicate that the potential predator–prey relationships within the microbiome, mediated by plant rhizosphere, might contribute to plant performance in agricultural ecosystems. [ABSTRACT FROM AUTHOR]

[Display omitted] • Inoculation of thermophilic bacterial consortia promoted the compost efficiency. • P V , n/P III , n values revealed the humification degree in different treatments. • Core microbes drove the variations in compost temperature, TOC, TN, and HAC. • Microbial community functions were closely related to compost quality. The objective of this study was to investigate the potential effects of thermophilic bacterial consortia on compost efficiency and quality. The application of bacterial consortia resulted in an earlier onset of the thermophilic period (THP), an increased upper temperature limit, and an extended duration of the THP by 3–5 days compared to the control group (CK). Microbial inoculation significantly improved the efficiency of organic matter degradation, as well as the content of water-soluble nitrogen (WSN) and humic acid-carbon (HAC). In the case of consortium Ⅱ inoculation (T2), the activities of cellobiohydrolase, β-glucosidase, and protease were increased by 81.81 %, 70.13 %, and 74.09 % at the THP respectively compared to CK. During the maturation stage, T2 also exhibited the highest P V , n/P III , n value (1.33) and HAC content (39.53 mg·g−1), indicating that inoculation of consortium Ⅱ effectively promoted substrate maturity and product quality. Moreover, this inoculation effectively optimized the bacterial communities, particularly the growth of Planococcus, Chelatococcus, and Chelativorans during the composting, which were involved in carbon and nitrogen conversion or HAC synthesis. Carbohydrate and amino acid metabolism, and membrane transport were predominant in the consortia-inoculated samples, with an increased gene abundance, suggesting that inoculation contributed to promoting the biodegradation of lignocellulose and the exchange of favorable factors. In conclusion, this study demonstrates that inoculating thermophilic bacterial consortia has a positive impact on enhancing the resource utilization efficiency of agricultural waste and improving the quality of compost products. [ABSTRACT FROM AUTHOR]

Soil aggregates contain distinct physio-chemical properties across different size classes. These differences in micro-habitats support varied microbial communities and modulate the effect of plant on microbiome, which affect soil functions such as disease suppression. However, little is known about how the residents of different soil aggregate size classes are impacted by plants throughout their growth stages. Here, we examined how tomato plants impact soil aggregation and bacterial communities within different soil aggregate size classes. Moreover, we investigated whether aggregate size impacts the distribution of soil pathogen and their potential inhibitors. We collected samples from different tomato growth stages: before-planting, seedling, flowering, and fruiting stage. We measured bacterial density, community composition, and pathogen abundance using qPCR and 16 S rRNA gene sequencing. We found the development of tomato growth stages negatively impacted root-adhering soil aggregation, with a gradual decrease of large macro-aggregates (1–2 mm) and an increase of micro-aggregates (<0.25 mm). Additionally, changes in bacterial density and community composition varied across soil aggregate size classes. Furthermore, the pathogen exhibited a preference to micro-aggregates, while macro-aggregates hold a higher abundance of potential pathogen-inhibiting taxa and predicted antibiotic-associated genes. Our results indicate that the impacts of tomatoes on soil differ for different soil aggregate size classes throughout different plant growth stages, and plant pathogens and their potential inhibitors have different habitats within soil aggregate size classes. These findings highlight the importance of fine-scale heterogeneity of soil aggregate size classes in research on microbial ecology and agricultural sustainability, further research focuses on soil aggregates level could help identify candidate tax involved in suppressing pathogens in the virtual micro-habitats. [ABSTRACT FROM AUTHOR]

Summary: Rhizomicrobiome plays important roles in plant growth and health, contributing to the sustainable development of agriculture. Plants recruit and assemble the rhizomicrobiome to satisfy their functional requirements, which is widely recognized as the 'cry for help' theory, but the intrinsic mechanisms are still limited.In this study, we revealed a novel mechanism by which plants reprogram the functional expression of inhabited rhizobacteria, in addition to the de novo recruitment of soil microbes, to satisfy different functional requirements as plants grow. This might be an efficient and low‐cost strategy and a substantial extension to the rhizomicrobiome recruitment theory.We found that the plant regulated the sequential expression of genes related to biocontrol and plant growth promotion in two well‐studied rhizobacteria Bacillus velezensis SQR9 and Pseudomonas protegens CHA0 through root exudate succession across the plant developmental stages. Sixteen key chemicals in root exudates were identified to significantly regulate the rhizobacterial functional gene expression by high‐throughput qPCR.This study not only deepens our understanding of the interaction between the plant–rhizosphere microbiome, but also provides a novel strategy to regulate and balance the different functional expression of the rhizomicrobiome to improve plant health and growth. [ABSTRACT FROM AUTHOR]

Improving rice nitrogen utilization efficiency (NUtE) is imperative to maximizing future food productivity while minimizing environmental threats, yet knowledge of its variation and the underlying regulatory factors is still lacking. Here, we integrated a dataset with 21,571 data compiled by available data from peer‐reviewed literature and a large‐scale field survey to address this knowledge gap. The overall results revealed great variations in rice NUtE, which were mainly associated with human activities, climate conditions, and rice variety. Specifically, N supply rate, temperature, and precipitation were the foremost determinants of rice NUtE, and NUtE responses to climatic change differed among rice varieties. Further prediction highlighted the improved rice NUtE with the increasing latitude or longitude. The indica and hybrid rice exhibited higher NUtE in low latitude regions compared to japonica and inbred rice, respectively. Collectively, our results evaluated the primary drivers of rice NUtE variations and predicted the geographic responses of NUtE in different varieties. Linking the global variations in rice NUtE with environmental factors and geographic adaptability provides valuable agronomic and ecological insights into the regulation of rice NUtE. [ABSTRACT FROM AUTHOR]

The RIPENING-INHIBITOR (RIN) transcriptional factor is a key regulator governing fruit ripening. While RIN also affects other physiological processes, its potential roles in triggering interactions with the rhizosphere microbiome and plant health are unknown. Here we show that RIN affects microbiome-mediated disease resistance via root exudation, leading to recruitment of microbiota that suppress the soil-borne, phytopathogenic Ralstonia solanacearum bacterium. Compared with the wild-type (WT) plant, RIN mutants had different root exudate profiles, which were associated with distinct changes in microbiome composition and diversity. Specifically, the relative abundances of antibiosis-associated genes and pathogen-suppressing Actinobacteria (Streptomyces) were clearly lower in the rhizosphere of rin mutants. The composition, diversity, and suppressiveness of rin plant microbiomes could be restored by the application of 3-hydroxyflavone and riboflavin, which were exuded in much lower concentrations by the rin mutant. Interestingly, RIN-mediated effects on root exudates, Actinobacteria, and disease suppression were evident from the seedling stage, indicating that RIN plays a dual role in the early assembly of disease-suppressive microbiota and late fruit development. Collectively, our work suggests that, while plant disease resistance is a complex trait driven by interactions between the plant, rhizosphere microbiome, and the pathogen, it can be indirectly manipulated using "prebiotic" compounds that promote the recruitment of disease-suppressive microbiota. The RIPENING-INHIBITOR (RIN) gene in tomato is well known for its role in regulating hormone metabolism and fruit ripening. This study shows that RIN is also important for plant immunity through root exudation-mediated recruitment of disease-suppressive microbiota. [ABSTRACT FROM AUTHOR]

[Display omitted] [ABSTRACT FROM AUTHOR]

Pathogen detection from biological and environmental samples is important for global disease control. Despite advances in pathogen detection using deep learning, current algorithms have limitations in processing long genomic sequences. Through the deep cross-fusion of cross, residual and deep neural networks, we developed DCiPatho for accurate pathogen detection based on the integrated frequency features of 3-to-7 k-mers. Compared with the existing state-of-the-art algorithms, DCiPatho can be used to accurately identify distinct pathogenic bacteria infecting humans, animals and plants. We evaluated DCiPatho on both learned and unlearned pathogen species using both genomics and metagenomics datasets. DCiPatho is an effective tool for the genomic-scale identification of pathogens by integrating the frequency of k-mers into deep cross-fusion networks. The source code is publicly available at https://github.com/LorMeBioAI/DCiPatho. [ABSTRACT FROM AUTHOR]

Summary: One model of a disease‐suppressive soil predicts that the confrontation of plant with a phytopathogen can lead to the recruitment and accumulation of beneficial microorganisms. However, more information needs to be deciphered regarding which beneficial microbes become enriched, and how the disease suppression is achieved.Here, we conditioned soil by continuously growing eight generations of cucumber inoculated with Fusarium oxysporum f.sp. cucumerinum in a split‐root system.Disease incidence was found to decrease gradually upon pathogen infection accompanied with higher quantity of reactive oxygen species (ROS mainly OH•) in roots and accumulation of Bacillus and Sphingomonas. These key microbes were proven to protect the cucumber from pathogen infection by inducing high ROS level in the roots through enrichment of pathways, including a two‐component system, a bacterial secretion system, and flagellar assembly revealed by metagenomics sequencing. Untargeted metabolomics analysis combined with in vitro application assays suggested that threonic acid and lysine were pivotal to recruit Bacillus and Sphingomonas.Collectively, our study deciphered a 'cry for help' case, wherein cucumber releases particular compounds to enrich beneficial microbes that raise the ROS level of host to prevent pathogen attack. More importantly, this may be one of the fundamental mechanisms underpinning disease‐suppressive soil formation. [ABSTRACT FROM AUTHOR]

[Display omitted] • The mesocosm experiment was used to track bacterial community dynamics. • Organic amendments increase the bacterial diversity during drought stress. • Organic amendments increase the compositional resilience during rewetting. • Pathogen inhibition ability in NOF was enhanced after rewetting. • NOF possesses a strategy-balancing community during whole drought event. The soil bacterial microbiome plays a crucial role in ecosystem functioning. The composition and functioning of the microbiome are tightly controlled by the physicochemical surrounding. Therefore, the microbiome is responsive to management, such as fertilization, and to climate change, such as extreme drought. It remains a challenge to retain microbiome functioning under drought. This work aims to reveal if fertilization with organic fertilizer, can enhance resistance and resilience of bacterial communities and their function in extreme drought and subsequent rewetting compared with conventional fertilizers. In soil mesocosms, we induced a long-term drought for 80 days with subsequent rewetting for 170 days to follow bacterial community dynamics in organic (NOF) and chemical (NCF) fertilization regimes. Our results showed that bacterial diversity was higher with NOF than with NCF during drought. In particular, the ecological resilience and recovery of bacterial communities under NOF were higher than in NCF. We found these bacterial community features to enhance pathogen-inhibiting functions in NOF compared to NCF during late recovery. The other soil ecology functional analyses revealed that bacterial biomass recovered in the early stage after rewetting, while soil respiration increased continuously following prolonged time after rewetting. Together, our study indicates that organic fertilization can enhance the stability of the soil microbiome and ensures that specific bacterial-driven ecosystem functions recover after rewetting. This may provide the basis for more sustainable agricultural practices to counterbalance negative climate change-induced effects on soil functioning. [ABSTRACT FROM AUTHOR]

Summary: Host‐associated fungi can help protect plants from pathogens, and empirical evidence suggests that such microorganisms can be manipulated by introducing probiotic to increase disease suppression. However, we still generally lack the mechanistic knowledge of what determines the success of probiotic application, hampering the development of reliable disease suppression strategies.We conducted a three‐season consecutive microcosm experiment in which we amended banana Fusarium wilt disease‐conducive soil with Trichoderma‐amended biofertilizer or lacking this inoculum. High‐throughput sequencing was complemented with cultivation‐based methods to follow changes in fungal microbiome and explore potential links with plant health.Trichoderma application increased banana biomass by decreasing disease incidence by up to 72%, and this effect was attributed to changes in fungal microbiome, including the reduction in Fusarium oxysporum density and enrichment of pathogen‐suppressing fungi (Humicola). These changes were accompanied by an expansion in microbial carbon resource utilization potential, features that contribute to disease suppression. We further demonstrated the disease suppression actions of Trichoderma‐Humicola consortia, and results suggest niche overlap with pathogen and induction of plant systemic resistance may be mechanisms driving the observed biocontrol effects.Together, we demonstrate that fungal inoculants can modify the composition and functioning of the resident soil fungal microbiome to suppress soilborne disease. [ABSTRACT FROM AUTHOR]

Seed‐borne pathogens can inhabit the rhizosphere and infect the plant after germination. The rhizosphere microbiome plays critical roles in defending against seed‐borne pathogens. However, the assembly of a core rhizosphere microbiome to suppress seed‐borne pathogens is unknown. Here, the root‐associated microbiome is infested with seed‐borne Fusarium in sterile environment, while the root‐associated microbiome is not infested when it interacts with the native soil microbiome across maize cultivars, suggesting that a core rhizosphere microbiome assembles to suppress seed‐borne Fusarium. Two strategies of progressive dilution and rhizodepositional attraction are applied to identify the core rhizobacteria. A synthetic microbiota (SynM) is constructed using the isolates of the core rhizobacteria and optimized according to superior community stability and Fusarium‐suppression capability, which surpasses the single strain and randomly formed microbiota. The optimized SynM (OptSynM) presents a distinctive cooperative pattern in which a key strain harbors the Fusarium suppression function by synthesizing the antagonistic substance fengycin, while other members intensify the functional performance by promoting the growth and the expression of the antagonistic and plant‐growth‐promoting related genes of the key strain. This study demonstrates innovative approaches to construct stable and minimal microbiota for sustainable agriculture and proposes a unique cooperative pattern to sustain community stability and functionality. [ABSTRACT FROM AUTHOR]

In this study, the growth of fungi Trichoderma guizhouense NJAU4742 was significantly inhibited under acid stress, and the genes related to acid stress were identified based on transcriptome analysis. Four genes including tna1, adh2/4, and bna3 were significantly up‐regulated. Meanwhile, intracellular hydrogen ions accumulated under acid stress, and ATP synthesis was induced to transport hydrogen ions to maintain hydrogen ion balance. The enhancement of glycolysis pathway was also detected, and a large amount of pyruvic acid from glycolysis was accumulated due to the activity limitation of PDH enzymes. Finally, acetaldehyde accumulated, resulting in the induction of adh2/4. In order to cope with stress caused by acetaldehyde, cells enhanced the synthesis of NAD+ by increasing the expression of tna1 and bna3 genes. NAD+ effectively improved the antioxidant capacity of cells, but the NAD+ supplement pathway mediated by bna3 could also cause the accumulation of kynurenine (KYN), which was an inducer of apoptosis. In addition, KYN had a specific promoting effect on acetaldehyde synthesis by improving the expression of eno2 gene, which led to the extremely high intracellular acetaldehyde in the cell under acidic stress. Our findings provided a route to better understand the response of filamentous fungi under acid stress. [ABSTRACT FROM AUTHOR]

The underground root–soil–microbe interactions are extremely complex, but vitally important for aboveground plant growth, health and fitness. The pressure to reduce our reliance on agrochemicals, and sustainable efforts to develop agriculture makes rhizosphere interactions’ research a hotspot. Recent advances provide new insights about the signals, pathways, functions and mechanisms of these interactions. In this review, we provide an overview about recent progress in rhizosphere interaction networks in crops. We also discuss a holistic view of the root–soil–rhizomicrobiome interactions achieved through the advances of omics and bioinformatics technologies, and the potential strategies to manage the complex rhizosphere interactions for enhancing crop production. [ABSTRACT FROM AUTHOR]

Characterizing microbial communities associated with disease-suppressive soil is an important first step toward understanding the potential of microbiota to protect crops against plant pathogens. In the present study, we compared microbial communities in suppressive- and conducive-soils associated with Fusarium wilt disease in a vanilla long-term continuous cropping system. Suppressive soil was associated with higher fungal diversity and lower bacterial diversity. The fungal phyla Zygomycota and Basidiomycota , and the bacterial phyla Acidobacteria , Verrucomicrobia , Actinobacteria and Firmicutes were strongly enriched in the suppressive soil. Notably, suppressive soil was dominated by the fungal genus Mortierella , accounting for 37% of the total fungal sequences. The hyper-dominance of Mortierella spp. in suppressive soil suggests that this taxon may serve as an indicator and enhancer of Fusarium wilt disease suppression in vanilla. In addition, Molecular Ecological Network analysis revealed that fungal communities were more connected and showed more co-occurrence relationships in the suppressive versus conducive soils. Our results indicate that fungal communities may be important in the development of soil suppressiveness against vanilla Fusarium wilt disease. [ABSTRACT FROM AUTHOR]

A new series of 4,5-diaryl-3 H -1,2-dithiole-3-thiones and related compounds were designed and synthesised as combretastatin A-4/oltipraz hybrids. We evaluated the antiproliferative activities, inhibition of tubulin polymerization, and cell-cycle effects of these compounds. Several compounds in this series, such as 4d and 5c , displayed significant activity against SGC-7901, KB and HT-1080 cell lines, as determined using MTT assays. The most active compound, 4d , markedly inhibited tubulin polymerization, with an IC 50 value of 4.44 μM being observed. In mechanistic studies, 4d caused cell arrest in G2/M phase, induced apoptotic cell death, and disrupted microtubule formation. Molecular docking studies revealed that 4d interacts and binds efficiently with the tubulin protein. [ABSTRACT FROM AUTHOR]

Microbial interactions within resident communities are a major determinant of resistance to pathogen invasion. Yet, interactions vary with environmental conditions, raising the question of how community composition and environments interactively shape invasion resistance. Here, we use resource availability (RA) as a model parameter altering the resistance of model bacterial communities to invasion by the plant pathogenic bacterium Ralstonia solanacearum. We found that at high RA, interactions between resident bacterial species were mainly driven by the direct antagonism, in terms of the means of invader inhibition. Consequently, the competitive resident communities with a higher production of antibacterial were invaded to a lesser degree than facilitative communities. At low RA, bacteria produced little direct antagonist potential, but facilitative communities reached a relatively higher community productivity, which showed higher resistance to pathogen invasion than competitive communities with lower productivities. This framework may lay the basis to understand complex microbial interactions and biological invasion as modulated by the dynamic changes of environmental resource availability. [ABSTRACT FROM AUTHOR]

Bacillus is a genus of microorganisms (bacteria) and contains many important commercial species used in industry, agriculture and healthcare. Many different Bacilli are relatively well understood at the single-cell level; however, molecular tools that determine the diversity and ecology of Bacillus community are limited, which limits our understanding of how the Bacillus community works. In the present study, we investigated the potential of the housekeeping gene gyrA as a molecular marker for determining the diversity of Bacillus species. The amplification efficiency for Bacillus species diversity could be greatly improved by primer design. Therefore, we designed a novel primer pair gyrA3 that can detect at least 92 Bacillus species and related species. For B. amyloliquefaciens, B. pumilus, and B. megaterium, we observed that the high variability of the gyrA gene allows for more detailed clustering at the subspecies level that cannot be achieved by the 16S rRNA gene. Since gyrA provides better phylogenetic resolution than 16S rRNA and informs on the diversity of the Bacillus community, we propose that the gyrA gene may have broad application prospects in the study of Bacillus ecology. [ABSTRACT FROM AUTHOR]

[Display omitted] • Microbial generalists and specialists were investigated at the global scale. • Generalists and specialists simultaneously contributed to species interactions. • Generalists had higher diversification and transition rates than specialists. • Generalists were more characterized by stochastic processes than specialists. • Generalists dampened microbial biogeographical patterns. Microbial generalists and specialists are thought to have distinct impacts on community dynamics, while there have been limited efforts to estimate their contribution to microbial diversity. We aimed to resolve this research gap in microbial ecology to strengthen our understanding of the biogeography of microbial diversity, with implications for global-scale biodiversity mapping. Herein, we identified the ecological characteristics of microbial generalists and specialists across over 3,000 farmland soil samples from eleven countries that encompassed seven climate types. Considering the distinct distributions of generalists and specialists in degree of connexions, betweenness and as key species in network topology, both generalists and specialists contributed to species interactions, though through different modalities. A stronger signature of deterministic processes in specialists indicated their lower tolerance to environment fluctuations. Generalists, in contrast, were more characterized by stochastic processes with higher diversification and transition rates that suggested more important roles in maintaining community stability when exposed to environmental disturbances. The relationship between latitude and diversity combining with distance-decay effects showed that generalists dampened microbial biogeographical patterns, with contrasting impacts by specialists. By demonstrating the ecological characteristics of microbial generalists and specialists, this study deepens our understanding of microbial diversity and highlights the need to impart systematic distinctions among different categories of species when modelling and predicting the fate of ecosystems in the face of global climate change, rather than assuming that species are functionally equivalent. [ABSTRACT FROM AUTHOR]

Summary: Stimulating the development of soil suppressiveness against certain pathogens represents a sustainable solution toward reducing pesticide use in agriculture. However, understanding the dynamics of suppressiveness and the mechanisms leading to pathogen control remain largely elusive.Here, we investigated the mechanisms used by the rhizosphere microbiome induces bacterial wilt disease suppression in a long‐term field experiment where continuous application of bio‐organic fertilizers (BFs) triggered disease suppressiveness when compared to chemical fertilizer application. We further demonstrated in a glasshouse experiment that the suppressiveness of the rhizosphere bacterial communities was triggered mainly by changes in community composition rather than only by the abundance of the introduced biocontrol strain.Metagenomics approaches revealed that members of the families Sphingomonadaceae and Xanthomonadaceae with the ability to produce secondary metabolites were enriched in the BF plant rhizosphere but only upon pathogen invasion. We experimentally validated this observation by inoculating bacterial isolates belonging to the families Sphingomonadaceae and Xanthomonadaceae into conducive soil, which led to a significant reduction in pathogen abundance and increase in nonribosomal peptide synthetase gene abundance.We conclude that priming of the soil microbiome with BF amendment fostered reactive bacterial communities in the rhizosphere of tomato plants in response to biotic disturbance. [ABSTRACT FROM AUTHOR]

Nematodes exert top-down control on the microbially-mediated processes of decomposition and nutrient cycling due to their position in the soil food web. Fertilization of agricultural soils can increase substrates for nematode populations, but whether the nematode community response to fertilization is consistent under anaerobic and aerobic soil conditions is not known. Our study investigated how soil nematode abundance and community structure responded to fertilization of a double-cropping system with paddy rice, representing anaerobic soil conditions due to flooding, followed an upland wheat phase that was rainfed and predominantly aerobic. We examined nematode communities twice a year from 2011 to 2013 at the ripening stage of rice (October) or wheat (June). Five fertilizer treatments were compared, including control (CK), chemical fertilizer (CF), compound pig manure-chemical fertilizer (MCF), straw plus chemical fertilizer (SCF) and pig manure plus straw plus chemical fertilizer (MSCF). Total nematode abundance increased by fertilization consistently in the rice and wheat cropping phases, and straw addition (i.e. SCF and MSCF) showed higher increment than manure addition (i.e. MCF) and CF treatments. However, dominant nematode genera respond to fertilization differently, depending on the crop phase. This is because dominant genera in the anaerobic soils of the rice phase were the plant-feeding nematode Hirschmanniella and algae-feeding nematode Rhabdolaimus , whereas dominant genera in the aerobic soils of the wheat phase were the fungal-feeding nematode Filenchus and bacterial-feeding nematodes Cephalobus , Eucephalobus and Acrobeloides . The manure addition (i.e. MCF) significantly raised Hirschmanniella abundance (by 133–616%) but sharply reduced the Rhabdolaimus population by 115–774% in the rice phase. In addition, straw addition (i.e. SCF and MSCF) increased Filenchus numbers (18–118%) but decreased the Acrobeloides population (49–145%) in the wheat phase. Since the MCF, SCF and MSCF fertilizers supply organic substrates for microbes and nutrients for plants, both of which are consumed by nematodes, this implies that food resources are the key determinant of total nematode abundance, the population size of all trophic levels. Our findings show that the nematode community structure is distinctive for each crop grown under a particular soil moisture regime, and that food resources derived from fertilizer inputs act as a bottom-up modulator of nematode population size in paddy rice–upland wheat systems. [ABSTRACT FROM AUTHOR]

Chemical nutrient amendment by human activities can lead to environmental impacts contributing to global biodiversity loss. However, the comprehensive understanding of how below- and above-ground biodiversity shifts under fertilization regimes in natural ecosystems remains elusive. Here, we conducted a seven-year field experiment (2011–2017) and examined the effects of different fertilization on plant biodiversity and soil belowground (prokaryotic and eukaryotic) communities in the alpine meadow of the Tibetan Plateau, based on data collected in 2017. Our results indicate that nitrogen addition promoted total plant biomass but reduced the plant species richness. Conversely, phosphorus enrichment did not promote plant biomass and exhibited an unimodal pattern with plant richness. In the belowground realm, distinct responses of soil prokaryotic and eukaryotic communities were observed under fertilizer application. Specifically, soil prokaryotic diversity decreased with nitrogen enrichment, correlating with shifts in soil pH. Similarly, soil eukaryotic diversity decreased with increased phosphorous inputs, aligning with the equilibrium between soil available and total phosphorus. We also established connections between these soil organism communities with above-ground plant richness and biomass. Overall, our study contributes to a better understanding of the sustainable impacts of human-induced nutrient enrichment on the natural environment. Future research should delve deeper into the long-term effects of fertilization on soil health and ecosystem functioning, aiming to achieve a balance between agricultural productivity and environmental conservation. • Soil prokaryotic and eukaryotic diversity decreased under nitrogen and phosphorus fertilization respectively. • Phosphorus fertilizer can alleviate nitrogen fertilizer induced soil acidification and promote soil diversity. • The changes of soil biodiversity were attributed to soil physicochemical characteristics induced by different fertilizer. • Soil prokaryotes and eukaryotes diversity was linked with the plant richness and biomass respectively. [ABSTRACT FROM AUTHOR]

Soil microbiomes play a pivotal role in shaping plant health and their ability to suppress the pathogens. However, the specific microbial features that confer disease suppression in agricultural soils have remained unknown. In this study, we aim to elucidate the mechanistic roles of soil key bacteria contributing to disease suppression in banana Panama disease by using a comprehensive soil survey focusing on suppressive, and conducive soils. Through an initial field survey across twelve paired locations, we identified five fields with significantly lower pathogen abundances compared to their co-located counterparts. Subsequent greenhouse experiments validated the disease-suppressive nature of soils collected from Jianfeng (JF) and Lingao (LG), both exhibiting low pathogen densities. Furthermore, four OTUs classified as Massilia (OTU44), Flavisolibacter (OTU396), Brevundimonas (OTU632) and Pseudomonas (OTU731), respectively, were identified as key players in suppressing pathogen invasion as they were significantly enriched in suppresive groups and pathogen inoculated treatments. The present results might suggest a vital link between these soil bacteria and pathogen inhibition in banana rhizosphere via a greenhouse experiment. The abundance of nonribosomal peptide synthetase (NRPS) genes, which was responsible for antibiotic synthesis and significantly enriched in the banana rhizosphere after beneficial microorganism inoculation, displayed a significant and negative correlation with pathogen abundance while a positive correlation with relative abundance of Pseudomonas. This result suggests that the up-regulation of NRPS genes may play a key role in bolstering banana plant immunity. These findings not only provide promising biocontrol strategies but also offer valuable insights into the dynamic relationship between soil microbiomes and plant physiology, paving the way for sustainable agriculture and disease management. [ABSTRACT FROM AUTHOR]

Hydrochar aging may mitigate the adverse effects of direct hydrochar application on plant growth. However, little is known about the strategies for accelerating aging process and the microbiological mechanisms involved. This study explored the effects of three aging strategies, including the addition of straw and efficient-degrading microorganisms, on the aging processes of food waste-derived hydrochar, and identified the key microbial drivers. The bacterial and fungal sequencing was performed to estimate the species composition in hydrochar at different aging periods (i.e., day 1, 7, 14 and 35). The results showed that the addition of straw and microbial inoculum improved the maximum reaction temperature by 13%, and shortened the aging time by ∼30%. Three bacterial guilds, mainly including Bacillus -like species, were identified that showed significant correlations with the nitrogen and phosphorus dynamics during aging. This study demonstrates the feasibility of manipulating key microbial guilds artificially to achieve efficient harmless-treatment of hydrochar. [Display omitted] • Straw and microbial inoculum addition reduced aging duration by 30%. • Microbial inoculum addition increases the aging reaction temperature by 13%. • Bacteria, rather than fungi, play the critical role in hydrochar aging. • Bacillus and related species drive nitrogen and phosphorus cycles of aging. [ABSTRACT FROM AUTHOR]