Sulfur-bearing minerals are key reservoirs in the global sulfur cycle, and microorganisms mediate sulfur release from these minerals. Labile carbon inputs may modify microbial sulfur metabolism, but their net effects on sulfide mineral oxidation remain unclear. Here, we conducted a 56-day soil incubation with glucose input and combined geochemical measurements, mineralogical characterization, qPCR, metagenomics, 16S rRNA amplicon sequencing, and DNA-stable isotope probing (DNA-SIP) to identify glucose-assimilating microorganisms and their roles in regulating sulfide mineral oxidation. Glucose significantly suppressed sulfide mineral oxidation, resulting in 60.00% lower sulfate (SO42-) and a 33.23% higher pH than the control by day 56. Glucose also reshaped microbial community and functions potentials. Sulfur-oxidizing bacteria (SOB) decreased, sulfatereducing bacteria (SRB) increased, and genes annotated in sulfur oxidation (soxB, soxX, soxY, soxZ) were depleted before day 42. This inhibition was reversed after glucose depletion, with sulfur oxidation genes becoming enriched. DNA-SIP using 13C-glucose linked Frateuria and Dyella to glucose assimilation and to the inhibitory phase of sulfur release. Glucose-amended microcosms maintained a lower redox potential and showed a delayed rise relative to the control, consistent with oxygen competition that may constrain sulfur oxidizers such as Bradyrhizobium. Notably, Dyella harbored a complete assimilatory sulfate reduction pathway, driven by ATP and NADPH produced through the central carbon metabolism (CCM). This metabolic coupling reduced oxygen availability for terminal sulfur oxidation, suggesting a dual mechanism of sulfur release suppression via both assimilatory reduction and respiratory competition. Our findings highlight a previously underappreciated link between labile carbon metabolism and sulfur cycling in soil. This mechanism offers insights into microbial controls over sulfur fluxes and presents implications for managing soil acidification and sulfur-driven water pollution in mineral-rich environments.

Soil health reflects the sustained capacity of soil to function as a vital living ecosystem, ensuring support for all forms of life. The evaluation of soil health relies heavily on physicochemical indicators. However, it remains unclear whether and how microbial traits are related to soil health in soil with long-term organic manure amendment. This study aims to examine how detrimental and beneficial microbial traits change with soil health based on physicochemical indicators. This research measures the effects of 9-year manure supplementation on soil health using multiomics techniques. We found that, compared to 100% chemical fertilizers, the soil health index increased by 5.2%, 19.3%, and 72.6% with 25%, 50%, and 100% organic fertilizer amendments, respectively. Correspondingly, the abundance of beneficial microorganisms, including Actinomadura, Actinoplanes, Aeromicrobium, Agromyces, Azospira, Cryobacterium, Dactylosporangium, Devosia, Hyphomicrobium, Kribbella, and Lentzea, increased progressively, while the abundance of the pathogenic fungus Fusarium decreased with the organic manure application rate. In addition, the application of organic manure significantly increased the concentrations of soil metabolites, such as sugars (raffinose, trehalose, maltose, and maltotriose) and lithocholic acid, which promoted plant growth and soil aggregation. Moreover, the abundances of pathogens and beneficial microorganisms and the concentrations of beneficial soil metabolites were significantly correlated with the soil health index based on physicochemical indicators. We conclude that organic fertilizer can enhance soil health by promoting the increase in beneficial microorganisms while suppressing detrimental microorganisms, which can serve as potential indicators for assessing soil health. In agricultural production, substituting 25–50% of chemical fertilizers with organic fertilizers significantly helps improve soil health and promotes crop growth.

Microbial traits are critical for carbon sequestration and degradation in terrestrial ecosystems. Yet, our understanding of the relationship between carbon metabolic strategies and genomic traits like genome size remains limited. To address this knowledge gap, we conducted a global-scale meta-analysis of 2650 genomes, integrated whole-genome sequencing data, and performed a continental-scale metagenomic field study. We found that genome size was tightly associated with an increase in the ratio between genes encoding for polysaccharide decomposition and biomass synthesis that we defined as the carbon acquisition-to-biomass yield ratio (A/Y). We also show that horizontal gene transfer played a major evolutionary role in the expanded bacterial capacities in carbon acquisition. Our continental-scale field study further revealed a significantly negative relationship between the A/Y ratio and soil organic carbon stocks. Our work demonstrates a global relationship between genome size and the encoded carbon metabolic strategies of soil bacteria across terrestrial microbiomes.

Ammonia oxidizers play an important role in nitrification that forms nitrate, the main form of leaching nitrogen (N). However, little is known about how ammonia oxidizers bridge long-term N fertilization levels and soil nitrate leaching. We conducted a field experiment in purple soil, investigating the interactions among soil physico-chemical parameters, ammonia-oxidizing microbial communities, and N leaching under 0, 90, 180, 270, and 360 kg N ha-1 yr-1 fertilization levels. We found that soil inorganic N leaching increased exponentially with increasing N application rate. N fertilization enhanced the abundances of the amoA gene in ammonia-oxidizing archaea (AOA) and bacteria (AOB), while partial least squares regression analysis revealed that AOA and AOB abundances were correlated with pH and soil organic carbon (SOC). Compared with no N fertilization, N application reduced AOA alpha diversity and increased AOB alpha diversity. AOA alpha diversity was associated with pH and bulk density, whereas soil SOC and inorganic N content were more important in predicting changes in AOB alpha diversity. A linear relationship was established between soil NO3--N leaching, the potential nitrification rate (PNR), and the abundances of AOA and AOB. The association of soil NO3--N leaching and PNR with both AOA and AOB abundances were further corroborated by Mantel test, random forest regression, and partial least squares path modelling. Furthermore, alterations in the AOB alpha diversity, soil pH and NH4+-N content also contribute to the increasing soil NO3--N leaching along the N application rate. Our results suggest that AOA, which previous studies have found to be active only under low N conditions, can also contribute to nitrification and support soil NO3--N leaching at a wide range of N gradients. Overall, this finding advances the current understanding of the relationship between soil N leaching and microbial functional properties to some extent.

Engineering root microbiomes holds great promise to enhance plant health. Enhanced plant resistance via breeding or genetic modification can promote recruiting beneficial microbes, but is challenging to achieve. Here we showed that calcium (Ca) addition caused significant changes in tomato physiology, resulting in enhanced immunity towards the pathogen Ralstonia solanacearum along with increased levels of salicylic acid (SA), sugar content, and defense enzyme activities in roots. High Ca levels significantly altered the root microbiomes, enriching sixteen bacterial genera, including Dyella japonica, Rhodanobacter glycinis, Paenibacillus polymyxa, and Pseudomonas aeruginosa, with the mostly enriched genus showing a 16.5-fold increase in the relative abundance compared to no Ca addition. Associated with the enhancement of these bacterial genera, tomato wilt incidence was reduced from 80 to 0

The soil microbiome plays an important role in carbon (C) and nitrogen (N) processing and storage and is influenced by rare earth elements (REEs), which can have both direct and indirect effects on plant metabolic processes. Using conventional physicochemical methods and metagenomic-based analyses, we investigated REEs effects on soil respiration, soil mineral N, soil microbial community structure and functional genes related to C and N metabolism. High doses of cerium (0.16 and 0.32 mmol kg- 1 soil) increased CO2 net production rate by 59 and 42%, and N2O net production rate by 255 and 609%, respectively, compared to no REEs. Similarly, high doses of lanthanum (0.16 and 0.32 mmol kg- 1 soil) increased CO2 net production rate by 47 and 39%, and N2O net production rate by 105 and 187%, respectively. Increased soil respiration from altered relative abundances of key soil microorganisms associated with soil N cycling and organic matter degradation and functional genes encoding enzymes involved in C and N metabolism, accelerated N mineralization. Elevated REEs levels substantially increased the relative abundances of functional genes related to cellulose, chitin, glucans, hemicellulose, lignin, and peptidoglycan degradation. REEs also influenced multiple functional genes associated with the N cycle. The abundance of genes responsible for organic N degradation and synthesis, such as asnB, gdh_K15371, glsA, and gs, increased with elevated cerium and lanthanum concentrations. Similarly, the abundances of denitrification genes, including narl, narJ, narZ, and nosZ, also rose with increasing amounts of cerium and lanthanum. However, the decrease in narB and nirB gene abundance with increasing REE concentrations was attributed to the reduction of nitrate to amino groups. Our findings highlight the influence of REEs on key soil microorganisms associated with soil N cycling and organic matter degradation and key functional genes in soil C and N metabolism, with implications for agriculture, environmental protection, and human health.

Aims: Diazotrophs are crucial for sustainable agriculture by converting atmospheric dinitrogen into plant-usable nitrogen through biological nitrogen fixation. Understanding how different agricultural practices affect diazotrophic communities can provide valuable insights for optimizing nitrogen management in crop production. Methods: Here, we employed the nifH gene as a molecular marker to assess the impact of 10 years of nitrogen fertilization and Bradyrhizobium inoculation on diazotrophic community structure. Treatments included no fertilization (CK), phosphorus plus potassium (PK), PK plus urea (PK + N), and PK plus Bradyrhizobium japonicum 5821 (PK + R). Results: At soybeans flowering-podding stage, Bradyrhizobium inoculation increased nifH gene copies but decreased the Shannon index in both bulk and rhizosphere soils compared to nitrogen fertilization. At maturity, Bradyrhizobium inoculation reduced nifH gene copies while increasing the Shannon index in both bulk and rhizosphere soils. Bradyrhizobium inoculation lowered beta diversity in the rhizosphere during the floweringpodding but increased it in mature bulk soil. The dominant diazotrophic genera were Bacillus, Azohydromonas, and Skermanella. Bradyrhizobium inoculation enhanced Bacillus abundance during flowering-podding but reduced it while boosting Azohydromonas and Skermanella during maturity. Overall, Bradyrhizobium inoculation decreased network complexity but increased diazotrophic dynamics compared to nitrogen fertilization. Conclusions: Long-term Bradyrhizobium inoculation fosters diazotrophic interactions more effectively than nitrogen fertilization.

Soil in high latitude and altitude cold regions contains over half of soil organic carbon (SOC) globally, so the decomposition of these SOCs under climate warming could release huge amounts of carbon dioxide to the atmosphere, amplifying climate warming. However, it is still unclear how the SOC storages will change when the ecosystem reaches the final and stable stage (i.e., the climax) under long-term warming. This is mainly because the turnover times of SOC in cold regions exceeds hundreds or even thousands of years, much longer than the periods of simulated warming experiments. Herein we used natural geothermal warming gradients in a Tibetan alpine grassland to determine SOC changes and underlying plant and microbial mechanisms at the potential climax. SOC concentrations were significantly decreased by 21.4%-30.6% under high-level soil warming (+4 similar to+6 degrees C), but remained unchanged under low-level soil warming (+2 degrees C). The losses of SOC were primarily from mineral-associated organic carbon, rather than unprotected particulate organic carbon. The shifts of microbial communities and associated decline of microbial carbon use efficiency, rather than plant-driven carbon fluxes, substantially contributed to the SOC changes. This observed SOC losses at the climax of alpine grassland by high-level warming provide strong empirical support for the positive soil carbon-climate feedback in cold regions, which could not be concluded from short-term experiments or only based on ecosystem carbon fluxes alone. The divergent responses of SOC to different degrees of warming suggest that models must account for these heterogeneous carbon dynamics for projecting future climate warming scenarios.

Manure application is a global approach for enhancing soil organic carbon (SOC) sequestration. However, the response of SOC decomposition in manure-applied soil to abrupt warming, often occurring during diurnal temperature fluctuations, remains poorly understood. We examined the effects of long-term (23 years) continuous application of manure on SOC chemical composition, soil respiration, and microbial communities under temperature shifts (15 vs 25 °C) in the presence of plant residues. Compared to soil without fertilizer, manure application reduced SOC recalcitrance indexes (i.e., aliphaticity and aromaticity) by 17.45 and 21.77%, and also reduced temperature sensitivity (Q10) of native SOC decomposition, plant residue decomposition, and priming effect by 12.98, 15.98, and 52.83%, respectively. The relative abundances of warm-stimulated chemoheterotrophic bacteria and fungi were lower in the manure-applied soil, whereas those of chemoautotrophic Thaumarchaeota were higher. In addition, the microbial network of the manure-applied soil was more interconnected, with more negative connections with the warm-stimulated taxa than soils without fertilizer or with chemical fertilizer applied. In conclusion, our study demonstrated that the reduced loss of SOC to abrupt warming by manure application arises from C chemistry modification, less warm-stimulated microorganisms, a more complex microbial community, and the higher CO2 intercepting capability by Thaumarchaeota.

Rare earth is physiologically active elements,which can affect the growth and development of plants,and plant roots can respond to exogenous plant growth regulators and regulate plant growth.Using tomato seedings as materials,the effects of lanthanum and cerium on the growth and root exudates of tomato seedlings were analyzed by hydroponic experiment. The results showed that the application concentration of rare earth elements at 0.05 mmol/kg promoted the increase of tomato plant height and leaf area,but inhibit them when the concentration reached 0.1 mmol/kg.The application of rare earth elements inhibited the growth of plant roots.The components and contents of tomato root exudates were identified and analyzed.There were 110 metabolites with significant difference between rare earth treatment and blank group,belonging to 10 secondary classifications and 38 tertiary classifications,among which the differences among Fatty acyls class ification,Carboxylic acids and derivatives class ification and Organoxygen compounds class ification were the most significant.However,the effect mechanism of various root exudates on tomato growth still needs to be further studied.

Microbial diversity is an important indicator of soil fertility and plays an indispensable role in farmland ecosystem sustainability. The short-term effects of fertilization and rhizobium inoculation on soil microbial diversity and community structure have been explored extensively; however, few studies have evaluated their long-term effects. Here, we applied quantitative polymerase chain reaction (qPCR) and amplicon sequencing to characterize the effect of 10-year fertilizer and rhizobium inoculation on bacterial communities in soybean bulk and rhizosphere soils at the flowering-podding and maturity stages. Four treatments were examined: non-fertilization control (CK), phosphorus and potassium fertilization (PK), nitrogen and PK fertilization (PK + N), and PK fertilization and Bradyrhizobium japonicum 5821 (PK + R). Long-term co-application of rhizobium and PK promoted soybean nodule dry weight by 33.94% compared with PK + N, and increased soybean yield by average of 32.25%, 5.90%, and 5.00% compared with CK, PK, and PK + N, respectively. The pH of PK + R was significantly higher than that of PK and PK + N at the flowering-podding stage. The bacterial abundance at the flowering-podding stage was positively correlated with soybean yield, but not at the maturity stage. The significant different class Gemmatimonadetes, and the genera Gemmatimonas, and Ellin6067 in soil at the flowering-podding stage were negatively correlated with soybean yield. However, the bacterial community at class and genus levels at maturity had no significant effect on soybean yield. The key bacterial communities that determine soybean yield were concentrated in the flowering-podding stage, not at maturity stage. Rhizosphere effect, growth period, and treatment synergies resulted in significant differences in soil bacterial community composition. Soil organic matter (OM), total nitrogen (TN), pH, and available phosphorus (AP) were the main variables affecting bacterial community structure. Overall, long-term co-application of rhizobium and fertilizer not only increased soybean yield, but also altered soil bacterial community structure through niche reconstruction and microbial interaction. Rhizobium inoculation plays key role in reducing nitrogen fertilizer application and promoting sustainable agriculture practices.

To obtain high maize yield (Zea mays L.), nitrogen (N) fertilizer is widely used across the world and has greatly altered soil microbial communities and influenced soil health. Increasing plant density is an effective strategy for increasing maize yield, while variations in soil microbial communities in response to plant density under high N levels have not been well-studied. In Northeast China, maize was grown at low (LD, 67,500 plants ha-1) and high (HD, 90,000 plants ha-1) densities, combined with three N application rates of 0, 200, and 400 kg N ha- 1yr- 1(N0, N200 and N400). Based on a six-year field experiment, key soil microbial characteristics and physicochemical properties of top soils (0-20 cm), as well as yield and vegetative parameters were examined. Compared with that of LD, the maize grain yield of HD increased 10.8 % across N application rates from 2012 to 2017 (P < 0.05), while no significant differences between N200 and N400 were observed. HD significantly increased microbial biomass carbon (MBC), microbial biomass N (MBN), and bacterial and fungal diversity at N400 (P < 0.05). Dominant bacterial phyla across all samples were Proteobacteria, Acidobacteria, Actinobacteria and Thaumarchaeota, and fungal phyla were Ascomycota, Basidiomycota and Zygomycota. Species composition of HD shared more similarity between N200 and N400 than that of LD. HD significantly increased the abundance of Nitrososphaera and reduced the abundance of Pseudomonas and Sphingobium. From LD to HD, ammonia-oxidizing archaea (AOA) gene abundance increased while nirK gene abundance decreased at all N application rates, and ammonia oxidizing bacteria (AOB) and nirS gene abundances decreased at N0 and N400 but increased at N200 (P < 0.05). Shoot biomass and N uptake were positively correlated with MBC and MBN but negatively correlated with microbial community diversity. HD directly increased root biomass and N uptake, then reduced soil N contents (NH4+-N, NO3--N, and TN) and thus positively regulated soil microbial communities. Relative differences of diversity indexes and functional gene abundances between N application rates of HD were significantly lower than those of LD. Overall, our findings indicate that higher plant density of maize could mitigate the adverse effects of N fertilizer overuse on soil microbial communities, thus reconciling maize productivity and black soil health in Northeast China.

Diazotrophs play a dominant role in the sustainable agriculture due to their ability to convert atmospheric dinitrogen (N2) into plant-usable nitrogen via the process of biological nitrogen fixation (BNF). However, the effects of long-term rhizobium inoculation on the diazotrophic community structure remain poorly understood. Here, we employed the nifH gene as a molecular marker to investigate the influence of 10 years of rhizobium inoculation on the abundance and community structure of diazotrophs at the Amplicon Sequence Variant (ASV) level. The treatments consisted of no fertilization (CK), phosphorus plus potassium (PK), and PK plus Bradyrhizobium japonicum 5821 (PK+R). At the flowering-podding stage, rhizobium inoculation prevented soil acidification, and at the maturity stage, it increased the soil AP and AK contents. Furthermore, it enhanced soybean yield by an average of 737.73 kg ha-1 (32.25%) compared to CK, and by an average of 168.66 kg ha-1 (5.90%) compared to PK. Diazotrophic abundance and community composition were significantly influenced by treatment, rhizosphere effect, growth stage, and their combined effects. Rhizobium inoculation increased the abundance of the nifH gene in the rhizosphere soil at the flowering-podding stage and improved diazotroph richness and diversity in the rhizosphere soil at the maturity stage. Bacillus, Azohydromonas and Skermanella were the dominant diazotrophs in the different treatments. Rhizobium inoculation decreased the relative abundance of Bacillus and Azohydromonas but increased the relative abundance of Skermanella in the rhizosphere soil at maturity. In general, the network complexity and stability of diazotrophs were compromised by long-term rhizobium inoculation, in comparison with other treatments. Soil TN and NO3--N were identified as the primary factors influencing the diazotrophic community structure, while AP and AK showed a positive correlation with soybean yield. Overall, long-term rhizobium inoculation improved soybean yield, modified diazotrophic community structure, and potentially enhanced BNF in the rhizosphere soil.

Lignin and cellulose are the most important component of crop straw entering arable soil. The decomposition of lignin and cellulose are related to carbon sequestration and soil fertility. The keystone microbes decomposing lignin and cellulose in cropland and their impact on agricultural management, however, remains largely unclear. In this study, we traced the carbon (C) from highly enriched 13C-labeled (atom% 13C = 99 %) lignin and cellulose to functional keystone microbes in soils of a 26-year fertilization field experiment with stable isotope probing (SIP). 13C-cellulose and 13C-lignin decomposition were significantly accelerated with the long-term application of fertilization, especially with the combination of organic and chemical fertilization (NPKM). The 13C was mainly assimilated by bacteria Acidobacteria (i.e. GP1, GP3, GP6), Proteobacteria (i.e. unidentified gamaproteobactiera, Bradyrhizobium), and fungi Ascomycota (i.e. Talaromyces and Fusarium, etc.). The keystone bacteria taxa decomposing cellulose and lignin were large overlapped, but substantially shaped by fertilization. For instance, GP3 was the dominant bacterium that decomposed both cellulose and lignin in no fertilizer control (CK), while GP1 and GP6 were the ones in chemical fertilization (NPK) and NPKM, respectively. The decomposition rates of cellulose in different fertilizations were majorly predicted by soil total phosphorus (TP), functional fungi abundance, total nitrogen (TN), whereas functional bacterial and fungal abundance, TP, and community structure of functional fungi manipulated the decomposing rate of lignin. Together, we demonstrate that keystone functional microbes decomposing cellulose and lignin were largely concurring and significantly altered by long-term resources enrichment, which drives the similar patterns of decomposition rates of these two substrates along the resource enrichment gradient.

As a potent greenhouse gas, soil nitrous oxide (N2O) is strongly stimulated by rising temperature, triggering a positive feedback effect of global warming. However, its temperature sensitivity varies greatly among soils with different physical and chemical characteristics, while associated mechanisms remain unknown. Here we performed a meta-analysis of the effect of warming on N2O emission and found distinctions in the response of N2O to temperature increase in soils with different textures. Then, we conducted an incubation experiment on 11 arable soils with varying textures sampled across China. The results show that the temperature sensitivity of N2O emissions was lower as soil texture became more clayey and was consistent with the outcome of meta-analysis. Further analysis was conducted by classifying the soils into clay and loam subgroups. As shown in the clay soil subgroup, N2O emission was significantly correlated with both inorganic nitrogen contents and potential denitrification and nitrification activities. Correlation analysis and partial least square (PLS) path model revealed that temperature mediated N2O emission by regulating nosZ gene abundance indirectly. In loam soils, however, the indirect effect of temperature on N2O production was achieved mainly through nirS gene abundance. Additionally, soil DON content strongly correlated with N2O emission in both subgroups and affected N2O emissions by influencing the abundance of denitrifiers under warming conditions. Our findings suggest that (i) soil texture was an important factor affecting temperature sensitivity of N2O emission and (ii) variable efficacy of warming in soil N2O production might originate from the enriching DON and nitrate content and its different indirect effects on nirS- or nosZ-type denitrifiers.

为验证新型复合肥在大桃上的应用效果,为该产品的大面积推广提供一定的研究基础,本研究在北京市平谷区金海湖镇胡庄村设立试验点进行研究.通过测定施肥前后桃园的土壤有机质、碱解氮、速效磷、有效钾含量和pH,以及不施肥、农户常规处理和新型复合肥处理后的单果重、单株留果数、产量、果实硬度、可溶性固形物含量、可滴定酸含量、投入产出比等指标,分析新型复合肥在大桃上的应用肥效.研究发现,施用新型复合肥(N 14％、P2O59％、K2O 26％)颗粒后,显著提高大桃的果实单果重、 留果量和产量,提高桃果实硬度、可溶性固形物含量,显著降低桃可滴定酸含量,显著提高果实固酸比,显著改善果实的口感.施用新型复合肥能够显著提高农民的经济效益,建议大面积推广使用.

Microbial immobilization of fertilizer nitrogen (N) can effectively reduce N losses in soil. However, the effects of crop residue on microbial assimilation of fertilizer-N and the underlying microbial mechanisms in upland soils are unclear. We evaluated the influence of maize residue (13C) addition on the microbial assimilation of ammonium-N (15N) in DNA from fertilizer, and quantified the bacterial 13C or 15N assimilation by quantitative stable isotope probing (DNA-qSIP). We found that the straw addition did increase total microbial assimilation of ammonium from fertilizer during the 2-week incubation. However, bacterial taxa varied in their responses to straw addition: Bacteriodetes and Proteobacteria accounted for large fractions of ammonium assimilation and their N assimilations were increased, while N assimilations of Acidobacteria were decreased. We revealed that highly 13C-labeled taxa were the main contributors of N assimilation under straw addition. The straw primarily enhanced the contributions of bacterial taxa to ammonium assimilation through increasing the extent of N assimilation, or enhancing the abundance of the N-assimilating bacterial taxa. Overall, our study elucidated an interaction between microbial assimilation of fertilizer-N and straw-C, showing a close element coupling of the keystone functional microbial taxa in N immobilization driven by organic carbon.

为了探索不同磷形态处理下土壤、水稻根际和根内环境中细菌群落组成、结构、多样性,从而挖掘不同磷形态下水稻根际中介导植物-微生物相互作用的细菌群落特征.以籼稻(kasalath)为试验材料,采集南京的低磷土壤进行为期8周的水稻盆栽试验,采用高通量测序方法(16S rDNA Illumina测序),并结合土壤有效磷浓度和水稻生物学指标,分别比较不同磷形态处理下水稻生长和根际土、根内细菌微生物群落结构组成和多样性.研究发现,有机磷和无机磷处理显著提高了土壤有效磷含量和磷酸酶活性,其中与不加磷对照相比,无机磷处理显著提高了植株全磷含量,有机磷处理与无机磷处理无显著性差异;在根际土和根内细菌中,有机磷和对照处理植株细菌多样性均显著高于无机磷处理;不同磷形态下水稻的根系细菌多样性和丰富度均显著(P<0.001)低于根际和非根际土壤细菌多样性和丰富度指数.不同处理中主要细菌包括:厚壁菌门(Firmicutes)、变形菌门(Proteobacteria)、放线菌门(Actinobacteria)、酸杆菌门(Acidobacteria)、Ignavibacteriae、绿弯菌门(Chloroflexi).无机磷处理与对照、有机磷处理相比较,在根际土壤和根内细菌中微杆菌科(Microbacteriaceae)、链霉菌科(Streptomycetaceae)相对丰度较低,高温放线菌科(Thermoactinomycetace-ae)、Ignavibacteriaceae显著高于对照和有机磷处理,其中芽孢杆菌科(Bacillaceae)在根际、非根际土壤及根系相对丰度均低于对照和有机磷处理.根际土细菌多样性与植株全磷呈极显著负相关;根系细菌多样性与地上部生物量呈极显著负相关(P<0.01),与有效磷和磷酸酶活性呈显著负相关(P<0.05);根系细菌丰富度与有效磷呈显著负相关:非根际土壤细菌多样性与有效磷呈极显著负相关,与磷酸酶活性和植株全磷呈显著负相关;非根际土壤细菌多样性和丰富度均与有效磷呈极显著负相关,与磷酸酶活性和植株全磷呈显著负相关.本研究结果表明,不同磷形态对水稻根系微生物存在显著差异,无机磷比有机磷的作用更强,为理解磷形态-植物-微生物的相互关系提供了科学依据.