Soil Biology & Biochemistry最新文献_第7页

Priming effect on plant-derived mineral-associated organic C in paddy soil: a three-source partitioning study with a dual-13C approach 水稻土中植物源性矿物相关有机碳的启动效应：双13c方法下的三源分配研究

IF 10.3 1区农林科学 Q1 SOIL SCIENCE

Soil Biology & Biochemistry

Pub Date : 2026-03-01 Epub Date: 2025-12-22 DOI: 10.1016/j.soilbio.2025.110073

Yuhong Li , Jialing Wu , Qiong Liu , Jun Yuan , Falin Liu , Hongzhao Yuan , Kyle Mason-Jones , Yan Li , Jia Lu , Shaofeng Peng , Yongfu Li , Tida Ge

Mineral-associated organic matter (MAOM) represents a large and stable soil carbon (C) pool, yet its response to fresh labile C inputs—a key driver of priming effects (PEs)— could lead to significant impacts on soil C cycling. Although PEs have been extensively studied across various ecosystems, a knowledge gap remains regarding the specific soil organic carbon (SOC) pools involved, particularly key MAOM fractions such as iron-associated organic carbon (Fe-OC). Therefore, we employed a dual-isotope labelling approach (using glucose at two contrasting ¹³C enrichments) to trace the mineralization of ¹³C-enriched Fe-OC (derived from rice litter) and native SOC in response to glucose addition under flooded conditions. When added individually, the mineralization of Fe-OC (16.1 %) was lower than that of glucose (67.0 %). Glucose addition suppressed mineralization of both Fe-OC (from 16.1 % to 10.4 % of Fe-OC present) and native SOC (from 0.90 % to 0.78 % of SOC), demonstrating a negative priming effect. The negative priming intensity was correlated with glucose mineralization rates, and the suppression of mineralization was stronger for Fe-OC than for SOC. Based on the added:native Fe-OC ratio, 84.6 % of the negative PE was attributed to a reduction in MAOM mineralization. Our findings demonstrate that MAOM exhibits high responsiveness to labile C inputs, with its suppressed mineralization representing an underlying mechanism that may facilitate carbon sequestration in C-rich hotspots within paddy soils.

矿物伴生有机质（MAOM）代表了一个巨大而稳定的土壤碳(C)库，但其对新鲜稳定碳输入的响应（启动效应（PEs）的关键驱动因素）可能对土壤碳循环产生重大影响。尽管pe已经在不同的生态系统中得到了广泛的研究，但关于具体土壤有机碳（SOC）库的知识差距仍然存在，特别是关键的MAOM组分，如铁相关有机碳（Fe-OC）。因此，我们采用了双同位素标记方法（使用葡萄糖在两种不同的13C浓度下）来追踪13C富集的Fe-OC（来自水稻凋落物）的矿化和天然有机碳在淹水条件下对葡萄糖添加的响应。单独添加时，Fe-OC的矿化率（16.1%）低于葡萄糖的矿化率（67.0%）。葡萄糖的加入抑制了Fe-OC（从16.1%到10.4%）和天然SOC（从0.90%到0.78%）的矿化，表现出负启动效应。负启动强度与葡萄糖矿化率相关，且Fe-OC对矿化的抑制强于SOC。根据添加的原生Fe-OC比，负PE的84.6%归因于MAOM矿化的减少。我们的研究结果表明，MAOM对不稳定的C输入表现出高度的响应性，其抑制的矿化代表了可能促进水稻土中富含C热点的碳固存的潜在机制。

{"title":"Priming effect on plant-derived mineral-associated organic C in paddy soil: a three-source partitioning study with a dual-13C approach","authors":"Yuhong Li , Jialing Wu , Qiong Liu , Jun Yuan , Falin Liu , Hongzhao Yuan , Kyle Mason-Jones , Yan Li , Jia Lu , Shaofeng Peng , Yongfu Li , Tida Ge","doi":"10.1016/j.soilbio.2025.110073","DOIUrl":"10.1016/j.soilbio.2025.110073","url":null,"abstract":"<div><div>Mineral-associated organic matter (MAOM) represents a large and stable soil carbon (C) pool, yet its response to fresh labile C inputs—a key driver of priming effects (PEs)— could lead to significant impacts on soil C cycling. Although PEs have been extensively studied across various ecosystems, a knowledge gap remains regarding the specific soil organic carbon (SOC) pools involved, particularly key MAOM fractions such as iron-associated organic carbon (Fe-OC). Therefore, we employed a dual-isotope labelling approach (using glucose at two contrasting <sup>13</sup>C enrichments) to trace the mineralization of <sup>13</sup>C-enriched Fe-OC (derived from rice litter) and native SOC in response to glucose addition under flooded conditions. When added individually, the mineralization of Fe-OC (16.1 %) was lower than that of glucose (67.0 %). Glucose addition suppressed mineralization of both Fe-OC (from 16.1 % to 10.4 % of Fe-OC present) and native SOC (from 0.90 % to 0.78 % of SOC), demonstrating a negative priming effect. The negative priming intensity was correlated with glucose mineralization rates, and the suppression of mineralization was stronger for Fe-OC than for SOC. Based on the added:native Fe-OC ratio, 84.6 % of the negative PE was attributed to a reduction in MAOM mineralization. Our findings demonstrate that MAOM exhibits high responsiveness to labile C inputs, with its suppressed mineralization representing an underlying mechanism that may facilitate carbon sequestration in C-rich hotspots within paddy soils.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"214 ","pages":"Article 110073"},"PeriodicalIF":10.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145813856","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

A novel approach for calorespirometry: Integrating a CO2 sensor into an isothermal microcalorimeter for simultaneous measurement of microbial heat evolution and mineralization 一种新的热肺测量方法：将CO2传感器集成到等温微量热计中，用于同时测量微生物热演化和矿化

IF 10.3 1区农林科学 Q1 SOIL SCIENCE

Soil Biology & Biochemistry

Pub Date : 2026-03-01 Epub Date: 2025-11-21 DOI: 10.1016/j.soilbio.2025.110043

Shiyue Yang , Sven Paufler , Hauke Harms , Matthias Kästner , Anja Miltner , Thomas Maskow

Soil, as the largest terrestrial carbon sink, plays a crucial role in carbon sequestration. Within soil systems, microorganisms decompose soil organic matter to generate energy and obtain carbon for growth, concomitantly release heat and CO₂ as metabolic byproducts. The calorespirometric (CR) ratio – defined as the ratio of heat production to CO₂ evolution, is a key indicator of carbon use efficiency and soil anaerobicity. However, conventional methodologies typically measure heat and CO₂ separately, with CO₂ often quantified by intermittent sampling. This discontinuous approach, compounded by the inherent heterogeneity of soil, introduces uncertainties in calorespirometric analysis. To address this limitation, an infrared CO₂ sensor was mounted onto a stainless-steel calorimetric ampoule, containing soil-glucose mixtures, enabling simultaneous real-time measurements within an isothermal microcalorimeter. The novel configuration permits continuous monitoring of both parameters, validated through comparative analysis with traditional methods. The derived CR ratios aligned with theoretical predictions for carbohydrates metabolism. Furthermore, parallel oxygen measurements enabled quantification of CR ratio based on O₂ (heat-to-O₂), and the respiratory quotient (CO₂-to-O₂), offering deeper insight into microbial carbon-energy coupling and turnover in soil systems. This methodological advancement enhances the capacity to interrogate soil biogeochemical processes under dynamic environmental conditions.

土壤作为最大的陆地碳汇，在固碳中起着至关重要的作用。在土壤系统内，微生物通过分解土壤有机质产生能量，获取生长所需的碳，同时作为代谢副产物释放热量和二氧化碳。热肺比（CR）定义为产热与CO2演化的比值，是碳利用效率和土壤厌氧性的关键指标。然而，传统的方法通常是分别测量热量和二氧化碳，二氧化碳通常通过间歇性采样来量化。这种不连续的方法，再加上土壤固有的异质性，在热量计量分析中引入了不确定性。为了解决这一限制，将红外CO2传感器安装在含有土壤-葡萄糖混合物的不锈钢量热安瓿上，可以在等温微量热计内同时进行实时测量。新的配置允许连续监测这两个参数，并通过与传统方法的对比分析进行验证。所得的CR比率与碳水化合物代谢的理论预测一致。此外，平行氧气测量可以量化基于O2（热对氧）和呼吸商（co2对O2）的CR比，从而更深入地了解土壤系统中微生物的碳能耦合和周转。这种方法的进步提高了在动态环境条件下询问土壤生物地球化学过程的能力。

{"title":"A novel approach for calorespirometry: Integrating a CO2 sensor into an isothermal microcalorimeter for simultaneous measurement of microbial heat evolution and mineralization","authors":"Shiyue Yang , Sven Paufler , Hauke Harms , Matthias Kästner , Anja Miltner , Thomas Maskow","doi":"10.1016/j.soilbio.2025.110043","DOIUrl":"10.1016/j.soilbio.2025.110043","url":null,"abstract":"<div><div>Soil, as the largest terrestrial carbon sink, plays a crucial role in carbon sequestration. Within soil systems, microorganisms decompose soil organic matter to generate energy and obtain carbon for growth, concomitantly release heat and CO<sub>2</sub> as metabolic byproducts. The calorespirometric (CR) ratio – defined as the ratio of heat production to CO<sub>2</sub> evolution, is a key indicator of carbon use efficiency and soil anaerobicity. However, conventional methodologies typically measure heat and CO<sub>2</sub> separately, with CO<sub>2</sub> often quantified by intermittent sampling. This discontinuous approach, compounded by the inherent heterogeneity of soil, introduces uncertainties in calorespirometric analysis. To address this limitation, an infrared CO<sub>2</sub> sensor was mounted onto a stainless-steel calorimetric ampoule, containing soil-glucose mixtures, enabling simultaneous real-time measurements within an isothermal microcalorimeter. The novel configuration permits continuous monitoring of both parameters, validated through comparative analysis with traditional methods. The derived CR ratios aligned with theoretical predictions for carbohydrates metabolism. Furthermore, parallel oxygen measurements enabled quantification of CR ratio based on O<sub>2</sub> (heat-to-O<sub>2</sub>), and the respiratory quotient (CO<sub>2</sub>-to-O<sub>2</sub>), offering deeper insight into microbial carbon-energy coupling and turnover in soil systems. This methodological advancement enhances the capacity to interrogate soil biogeochemical processes under dynamic environmental conditions.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"214 ","pages":"Article 110043"},"PeriodicalIF":10.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145567786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Frequency and C:N:P stoichiometry of organic inputs determines intensity of net C balance in paddy soils 有机投入的频率和碳氮磷化学计量决定了水稻土净碳平衡的强度

IF 10.3 1区农林科学 Q1 SOIL SCIENCE

Soil Biology & Biochemistry

Pub Date : 2026-03-01 Epub Date: 2025-12-04 DOI: 10.1016/j.soilbio.2025.110051

Ruiqiao Wu , Ze Zhang , Guanjun Li , Xiangxiang Wang , Yunying Fang , Yakov Kuyakov , Xuebin Xu , Jianping Chen , Tida Ge , Zhenke Zhu

The frequency and nutrient composition of organic inputs jointly regulate soil organic carbon (SOC) dynamics, but their interactive effects on microbial carbon use efficiency (CUE), priming effects (PE), and net soil C balance remain poorly understood in flooded paddy systems. We performed a 40-day incubation experiment using a ¹³C-labeled simulated root-exudate mixture (glucose:oxalic acid:alanine, 65:30:5) under two input modes (single substrate input vs. continuous substrate input) and four C:N:P stoichiometries. Single substrate inputs generated an early pulse in labile-C mineralization that was 39–64 % greater than under continuous addition, and mineralization rates declined with increasing nutrient supply. Single-pulse addition triggered an early peak in the metabolic quotient (qCO₂) and lower tracer-based CUE, whereas continuous addition maintained steadier microbial activity and higher CUE. The C:N:P stoichiometry of the added substrate strongly controlled C partitioning: stoichiometrically balanced inputs reduced CO₂–C losses and increased ¹³C incorporation into microbial biomass and SOC pool. Pulse inputs typically induced negative PEs, whereas continuous inputs tended to cause positive PEs. Therefore, the net C balance was consistently greater following single substrate inputs than following continuous inputs; across nutrient treatments, single pulses produced substantially larger short-term C retention. Combining ¹³C tracing, enzyme assays and kinetic modelling, we demonstrate that under balanced nutrient inputs, microbes respire less of the added C and allocate more into biomass and necromass, which subsequently contributes to more stable SOC pool. This study provides mechanistic guidance for using C:N:P-balanced amendments to increase SOC retention in flooded cropping systems.

有机投入频率和养分组成共同调节土壤有机碳（SOC）动态，但它们对水淹稻田土壤微生物碳利用效率（CUE）、启动效应（PE）和土壤净碳平衡的交互作用尚不清楚。我们使用13c标记的模拟根渗出液混合物（葡萄糖：草酸：丙氨酸，65:30:5）在两种输入模式（单一底物输入与连续底物输入）和四种C:N:P化学计量学下进行了40天的培养实验。与连续添加相比，单一底物输入能产生较早的稳定碳矿化脉冲，且矿化率随养分供给的增加而下降。单脉冲添加可提前触发代谢商（qCO2）峰值和较低的示踪剂CUE，而连续添加可保持更稳定的微生物活性和较高的CUE。添加底物的C:N:P化学计量学控制了碳分配：化学计量学平衡的输入减少了CO2-C损失，增加了13C进入微生物生物量和SOC库的量。脉冲输入通常导致负pe，而连续输入往往导致正pe。因此，单一基质输入后的净C平衡始终大于连续输入后的净C平衡；在不同的营养处理中，单一脉冲产生了更大的短期碳潴留。结合13C示踪、酶分析和动力学模型，我们证明在平衡的营养输入下，微生物呼吸的增加的C较少，更多地分配到生物量和坏死体中，从而有助于更稳定的有机碳池。本研究为采用C:N: p平衡改良提高水淹作物系统有机碳保有量提供了机制指导。

{"title":"Frequency and C:N:P stoichiometry of organic inputs determines intensity of net C balance in paddy soils","authors":"Ruiqiao Wu , Ze Zhang , Guanjun Li , Xiangxiang Wang , Yunying Fang , Yakov Kuyakov , Xuebin Xu , Jianping Chen , Tida Ge , Zhenke Zhu","doi":"10.1016/j.soilbio.2025.110051","DOIUrl":"10.1016/j.soilbio.2025.110051","url":null,"abstract":"<div><div>The frequency and nutrient composition of organic inputs jointly regulate soil organic carbon (SOC) dynamics, but their interactive effects on microbial carbon use efficiency (CUE), priming effects (PE), and net soil C balance remain poorly understood in flooded paddy systems. We performed a 40-day incubation experiment using a <sup>13</sup>C-labeled simulated root-exudate mixture (glucose:oxalic acid:alanine, 65:30:5) under two input modes (single substrate input <em>vs.</em> continuous substrate input) and four C:N:P stoichiometries. Single substrate inputs generated an early pulse in labile-C mineralization that was 39–64 % greater than under continuous addition, and mineralization rates declined with increasing nutrient supply. Single-pulse addition triggered an early peak in the metabolic quotient (qCO<sub>2</sub>) and lower tracer-based CUE, whereas continuous addition maintained steadier microbial activity and higher CUE. The C:N:P stoichiometry of the added substrate strongly controlled C partitioning: stoichiometrically balanced inputs reduced CO<sub>2</sub>–C losses and increased <sup>13</sup>C incorporation into microbial biomass and SOC pool. Pulse inputs typically induced negative PEs, whereas continuous inputs tended to cause positive PEs. Therefore, the net C balance was consistently greater following single substrate inputs than following continuous inputs; across nutrient treatments, single pulses produced substantially larger short-term C retention. Combining <sup>13</sup>C tracing, enzyme assays and kinetic modelling, we demonstrate that under balanced nutrient inputs, microbes respire less of the added C and allocate more into biomass and necromass, which subsequently contributes to more stable SOC pool. This study provides mechanistic guidance for using C:N:P-balanced amendments to increase SOC retention in flooded cropping systems.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"214 ","pages":"Article 110051"},"PeriodicalIF":10.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145689063","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Organic nutrient amendments enhance the accrual of mineral associated soil organic carbon via microbial processes in a marginal Miscanthus agroecosystem 在芒草边缘农业生态系统中，有机养分修正通过微生物过程提高了矿物相关土壤有机碳的积累

IF 10.3 1区农林科学 Q1 SOIL SCIENCE

Soil Biology & Biochemistry

Pub Date : 2026-03-01 Epub Date: 2025-12-08 DOI: 10.1016/j.soilbio.2025.110063

Jennifer L. Kane , Ronald G. Schartiger , Zachary B. Freedman , Ember M. Morrissey

Interactivity between plants and microorganisms underpin the cycling and storage of carbon in soil, processes that are especially critical to understand on marginal lands. Nutrient amendments may impact these processes by shaping plant productivity and microbial activity with implications for the stabilization of carbon in soil organic matter (SOM). In year three of nutrient management, we investigated the impact of conventional (mineral N–P–K, 300 kg ha⁻¹) and organic (composted dairy manure, 57 kg N ha⁻¹) nutrient additions on Miscanthus x giganteus grown on marginal land. We surveyed plant productivity, microbial activity, and SOM pools (particulate and mineral-associated). Plant productivity increased with both conventional (+70 %) and organic (+94 %) nutrient amendments (p < 0.05). Using quantitative stable isotope probing (qSIP), we identified bacterial genera exhibiting increased C assimilation under each nutrient treatment (16 genera for organically amended plots and 9 genera for conventionally amended plots). At the community level, microbial activity was also responsive to nutrient treatments (e.g., +43 % and +50 % increases in microbial respiration rate for conventional and organic amendments respectively, p < 0.05). Soil carbon content in organically amended plots was 21 % higher than control plots and 27 % higher than conventionally fertilized plots (p < 0.05) with increases in both particulate and mineral-associated organic matter pools. Direct addition of carbon with the manure amendment could account for 44 % of the observed increase in particulate organic matter carbon but only 5 % of mineral-associated carbon gains, suggesting that stimulated microbial activity shapes carbon accrual under organic amendments. These results suggest that organic amendments may stimulate both plant productivity and microbially mediated soil carbon sequestration to meet agronomic and environmental goals simultaneously.

植物和微生物之间的相互作用是土壤中碳循环和储存的基础，这一过程对于了解边缘土地尤为重要。养分修正可能通过塑造植物生产力和微生物活动来影响这些过程，从而影响土壤有机质（SOM）中碳的稳定。在养分管理的第三年，我们研究了常规（矿质N - p - k， 300 kg ha - 1）和有机（堆肥牛粪，57 kg N - ha - 1）营养添加对边缘土地上生长的芒草的影响。我们调查了植物生产力、微生物活动和SOM池（颗粒和矿物相关）。常规（+ 70%）和有机（+ 94%）养分改良均能提高植物生产力（p < 0.05）。通过定量稳定同位素探测（qSIP），我们发现了在每种营养处理下都表现出碳同化增加的细菌属（有机改良样地16属，常规改良样地9属）。在群落水平上，微生物活性也对营养处理有响应（例如，常规和有机处理的微生物呼吸率分别增加43%和50%，p < 0.05）。土壤碳含量在有机改良地块比对照地块高21%，比常规施肥地块高27% (p < 0.05)，颗粒和矿物相关有机质库均增加。通过粪便改进剂直接添加的碳可以占到观察到的颗粒有机质碳增加的44%，但仅占矿物相关碳增加的5%，这表明受刺激的微生物活动决定了有机改进剂下的碳积累。这些结果表明，有机改良可能同时刺激植物生产力和微生物介导的土壤碳固存，以同时满足农艺和环境目标。

{"title":"Organic nutrient amendments enhance the accrual of mineral associated soil organic carbon via microbial processes in a marginal Miscanthus agroecosystem","authors":"Jennifer L. Kane , Ronald G. Schartiger , Zachary B. Freedman , Ember M. Morrissey","doi":"10.1016/j.soilbio.2025.110063","DOIUrl":"10.1016/j.soilbio.2025.110063","url":null,"abstract":"<div><div>Interactivity between plants and microorganisms underpin the cycling and storage of carbon in soil, processes that are especially critical to understand on marginal lands. Nutrient amendments may impact these processes by shaping plant productivity and microbial activity with implications for the stabilization of carbon in soil organic matter (SOM). In year three of nutrient management, we investigated the impact of conventional (mineral N–P–K, 300 kg ha<sup>−1</sup>) and organic (composted dairy manure, 57 kg N ha<sup>−1</sup>) nutrient additions on <em>Miscanthus x giganteus</em> grown on marginal land. We surveyed plant productivity, microbial activity, and SOM pools (particulate and mineral-associated). Plant productivity increased with both conventional (+70 %) and organic (+94 %) nutrient amendments (p < 0.05). Using quantitative stable isotope probing (qSIP), we identified bacterial genera exhibiting increased C assimilation under each nutrient treatment (16 genera for organically amended plots and 9 genera for conventionally amended plots). At the community level, microbial activity was also responsive to nutrient treatments (e.g., +43 % and +50 % increases in microbial respiration rate for conventional and organic amendments respectively, p < 0.05). Soil carbon content in organically amended plots was 21 % higher than control plots and 27 % higher than conventionally fertilized plots (p < 0.05) with increases in both particulate and mineral-associated organic matter pools. Direct addition of carbon with the manure amendment could account for 44 % of the observed increase in particulate organic matter carbon but only 5 % of mineral-associated carbon gains, suggesting that stimulated microbial activity shapes carbon accrual under organic amendments. These results suggest that organic amendments may stimulate both plant productivity and microbially mediated soil carbon sequestration to meet agronomic and environmental goals simultaneously.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"214 ","pages":"Article 110063"},"PeriodicalIF":10.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145732411","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Plant functional groups shape microbial colonization and decomposition dynamics in grassland soils 植物功能群影响草地土壤微生物定植和分解动态

IF 10.3 1区农林科学 Q1 SOIL SCIENCE

Soil Biology & Biochemistry

Pub Date : 2026-03-01 Epub Date: 2025-12-10 DOI: 10.1016/j.soilbio.2025.110067

Ramesha H. Jayaramaiah , Catarina S.C. Martins , Eleonora Egidi , Catriona A. Macdonald , Jun-Tao Wang , Nico Eisenhauer , Peter B. Reich , Manuel Delgado-Baquerizo , Brajesh K. Singh

Litter decomposition is a key ecosystem process that governs nutrient release and organic matter turnover in terrestrial ecosystems. While plants are known to influence rhizosphere microbiome, their role in shaping microbial colonization of litter, and further regulating decomposition remains less understood. Here, we employed a field-based Tea Bag Index (TBI) experiment to investigate how living plant functional groups (PFGs), including C3, C4, forb, and N₂-fixing legumes affect decomposition of standardized tea substrates (Green tea = labile; Rooibos tea = recalcitrant) and the associated microbial communities. Our results demonstrate that PFG type exerted a stronger influence on decomposition rate than species richness. The PFG impacts on decomposition were linked directly with shifts in substrate-colonizing communities, and indirectly with higher soil nitrate, N mineralization, and favourable moisture conditions. Microbial assemblages on Green vs Rooibos tea were distinct, indicating strong substrate filtering with PFG-mediated selection of decomposer communities. Across both substrates, PFGs and soil properties jointly explained most of the variance in decomposition rate, with additional, context-dependent contributions from bacterial and faunal (protist and metazoan) diversity reflecting their functional roles in litter breakdown. These findings underscore the central role of PFGs in structuring decomposer communities and regulating key soil processes. Preserving plant functional diversity is therefore essential for preserving microbial-mediated soil processes and ensuring grassland ecosystem resilience.

凋落物分解是陆地生态系统中控制养分释放和有机质周转的关键生态系统过程。虽然已知植物会影响根际微生物群，但它们在形成凋落物的微生物定植以及进一步调节分解方面的作用仍然知之甚少。在这里，我们采用基于田间的茶袋指数（TBI）实验来研究活植物功能群（PFGs），包括C3、C4、forb和固氮豆科植物，如何影响标准化茶叶基质（绿茶=不稳定；路易波士茶=顽固）的分解和相关的微生物群落。结果表明，PFG类型对分解速率的影响大于物种丰富度。PFG对分解的影响与底物定殖群落的变化直接相关，并与土壤硝酸盐、氮矿化和有利的水分条件间接相关。绿茶和路易波士茶的微生物组合不同，表明pfg介导的强底物过滤对分解者群落的选择。在这两种基质中，PFGs和土壤性质共同解释了分解率的大部分差异，细菌和动物（原生动物和后生动物）多样性的额外、依赖于环境的贡献反映了它们在凋落物分解中的功能作用。这些发现强调了PFGs在构建分解者群落和调节关键土壤过程中的核心作用。因此，保护植物功能多样性对于保护微生物介导的土壤过程和确保草原生态系统的恢复能力至关重要。

{"title":"Plant functional groups shape microbial colonization and decomposition dynamics in grassland soils","authors":"Ramesha H. Jayaramaiah , Catarina S.C. Martins , Eleonora Egidi , Catriona A. Macdonald , Jun-Tao Wang , Nico Eisenhauer , Peter B. Reich , Manuel Delgado-Baquerizo , Brajesh K. Singh","doi":"10.1016/j.soilbio.2025.110067","DOIUrl":"10.1016/j.soilbio.2025.110067","url":null,"abstract":"<div><div>Litter decomposition is a key ecosystem process that governs nutrient release and organic matter turnover in terrestrial ecosystems. While plants are known to influence rhizosphere microbiome, their role in shaping microbial colonization of litter, and further regulating decomposition remains less understood. Here, we employed a field-based Tea Bag Index (TBI) experiment to investigate how living plant functional groups (PFGs), including C3, C4, forb, and N<sub>2</sub>-fixing legumes affect decomposition of standardized tea substrates (Green tea = labile; Rooibos tea = recalcitrant) and the associated microbial communities. Our results demonstrate that PFG type exerted a stronger influence on decomposition rate than species richness. The PFG impacts on decomposition were linked directly with shifts in substrate-colonizing communities, and indirectly with higher soil nitrate, N mineralization, and favourable moisture conditions. Microbial assemblages on Green vs Rooibos tea were distinct, indicating strong substrate filtering with PFG-mediated selection of decomposer communities. Across both substrates, PFGs and soil properties jointly explained most of the variance in decomposition rate, with additional, context-dependent contributions from bacterial and faunal (protist and metazoan) diversity reflecting their functional roles in litter breakdown. These findings underscore the central role of PFGs in structuring decomposer communities and regulating key soil processes. Preserving plant functional diversity is therefore essential for preserving microbial-mediated soil processes and ensuring grassland ecosystem resilience.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"214 ","pages":"Article 110067"},"PeriodicalIF":10.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145731634","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Foliar phosphorus concentrations in Bahiagrass are well-predicted by the abundance of a Fusarium taxa 镰刀菌类群的丰度对百喜草叶片磷浓度有很强的预测作用

IF 10.3 1区农林科学 Q1 SOIL SCIENCE

Soil Biology & Biochemistry

Pub Date : 2026-03-01 Epub Date: 2025-11-29 DOI: 10.1016/j.soilbio.2025.110049

Daniel F. Petticord , Ran Zhi , Elizabeth H. Boughton , Yuxi Guo , Hui-Ling Liao , Alma L. Reyes , Jiangxiao Qiu , Jed P. Sparks

Sustaining agricultural productivity in phosphorus-poor soils requires innovation to reduce reliance on synthetic fertilizers. One underexplored solution is the role of fungi in enhancing plant phosphorus (P) acquisition. We examined fungal diversity in the rhizosphere and roots of Paspalum notatum, a globally important forage grass, across a soil P gradient in a subtropical pasture. Rhizosphere fungal communities were more diverse than those associated with roots, though root communities were more compositionally distinct among plants. Variation in foliar P concentrations was partially explained by plant-available P, percent carbon, and soil moisture (R² = 0.58). DESeq2 analysis identified two taxa whose relative abundance shifted with foliar P: a putative Fusarium variasi ASV that increased with P, and an unidentified Clavariaceae ASV that declined. Incorporating these taxa into regression models improved predictions of foliar P, with Total P and the Fusarium ASV together explaining 67.8 % of variation. Although this Fusarium ASV is labeled as a pathogen in the FungalTraits database, not all Fusarium strains negatively affect plants. Many are weakly pathogenic or beneficial, often promoting growth by suppressing more virulent pathogens through competition in the rhizosphere. A key mechanism underlying this competition is iron acquisition. We speculate that this same strategy may have an underrecognized side effect: mobilizing phosphorus from iron-bound pools. In highly weathered tropical soils, where calcium and magnesium are depleted and phosphorus is commonly occluded by iron oxides, such iron competition could indirectly enhance plant P availability. Our findings generate two non-exclusive hypotheses: (a) this Fusarium strain may provide genuine benefits by mobilizing P, or (b) its increased abundance may reflect low-virulence pathogenicity that suppresses biomass more than P uptake, effectively concentrating foliar P. These results highlight the need to reassess the ecological roles of rhizosphere Fusarium and related taxa—not only as potential pathogens but also as contributors to nutrient cycling in P-limited ecosystems.

在缺磷土壤中维持农业生产力需要创新，以减少对合成肥料的依赖。一个未被充分开发的解决方案是真菌在促进植物磷(P)获取中的作用。研究了全球重要牧草雀稗（Paspalum notatum）根际和根系中不同土壤磷梯度的真菌多样性。根际真菌群落的多样性高于根内真菌群落，但根间真菌群落的组成差异较大。植物速效磷、碳百分比和土壤水分可以部分解释叶片磷浓度的变化（R2 = 0.58）。DESeq2分析发现，两个类群的相对丰度随叶片磷含量的变化而变化：一个推测的变异镰刀菌ASV随磷含量的增加而增加，另一个未确定的Clavariaceae ASV则随磷含量的下降而下降。将这些分类群纳入回归模型，改进了对叶磷的预测，总磷和镰刀菌ASV共同解释了67.8%的变异。虽然这种镰刀菌ASV在FungalTraits数据库中被标记为病原体，但并不是所有的镰刀菌菌株都对植物有负面影响。许多是弱致病性或有益的，通常通过在根际竞争抑制毒性更强的病原体来促进生长。这种竞争背后的一个关键机制是铁的获取。我们推测，同样的策略可能有一个未被认识到的副作用：从铁结合池中动员磷。在高度风化的热带土壤中，钙和镁被耗尽，磷通常被氧化铁遮挡，这种铁竞争可能间接提高植物的磷有效性。我们的研究结果产生了两个非排他的假设：(a)这种镰刀菌菌株可能通过动员磷来提供真正的益处，或者(b)其丰度的增加可能反映了低毒力致病性，这种致病性抑制生物量多于磷的吸收，有效地集中了叶面磷。这些结果突出了重新评估根际镰刀菌和相关分类的生态作用的必要性-不仅是潜在的病原体，而且是磷限制生态系统中营养循环的贡献者。

{"title":"Foliar phosphorus concentrations in Bahiagrass are well-predicted by the abundance of a Fusarium taxa","authors":"Daniel F. Petticord , Ran Zhi , Elizabeth H. Boughton , Yuxi Guo , Hui-Ling Liao , Alma L. Reyes , Jiangxiao Qiu , Jed P. Sparks","doi":"10.1016/j.soilbio.2025.110049","DOIUrl":"10.1016/j.soilbio.2025.110049","url":null,"abstract":"<div><div>Sustaining agricultural productivity in phosphorus-poor soils requires innovation to reduce reliance on synthetic fertilizers. One underexplored solution is the role of fungi in enhancing plant phosphorus (P) acquisition. We examined fungal diversity in the rhizosphere and roots of <em>Paspalum notatum</em>, a globally important forage grass, across a soil P gradient in a subtropical pasture. Rhizosphere fungal communities were more diverse than those associated with roots, though root communities were more compositionally distinct among plants. Variation in foliar P concentrations was partially explained by plant-available P, percent carbon, and soil moisture (R<sup>2</sup> = 0.58). DESeq2 analysis identified two taxa whose relative abundance shifted with foliar P: a putative <em>Fusarium variasi</em> ASV that increased with P, and an unidentified <em>Clavariaceae</em> ASV that declined. Incorporating these taxa into regression models improved predictions of foliar P, with Total P and the <em>Fusarium</em> ASV together explaining 67.8 % of variation. Although this <em>Fusarium</em> ASV is labeled as a pathogen in the FungalTraits database, not all <em>Fusarium</em> strains negatively affect plants. Many are weakly pathogenic or beneficial, often promoting growth by suppressing more virulent pathogens through competition in the rhizosphere. A key mechanism underlying this competition is iron acquisition. We speculate that this same strategy may have an underrecognized side effect: mobilizing phosphorus from iron-bound pools. In highly weathered tropical soils, where calcium and magnesium are depleted and phosphorus is commonly occluded by iron oxides, such iron competition could indirectly enhance plant P availability. Our findings generate two non-exclusive hypotheses: (a) this <em>Fusarium</em> strain may provide genuine benefits by mobilizing P, or (b) its increased abundance may reflect low-virulence pathogenicity that suppresses biomass more than P uptake, effectively concentrating foliar P. These results highlight the need to reassess the ecological roles of rhizosphere <em>Fusarium</em> and related taxa—not only as potential pathogens but also as contributors to nutrient cycling in P-limited ecosystems.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"214 ","pages":"Article 110049"},"PeriodicalIF":10.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145613436","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Belowground perspectives: how plant functional type clipping reshapes soil fungal communities across peat depths 地下视角：植物功能类型修剪如何重塑泥炭深度的土壤真菌群落

IF 10.3 1区农林科学 Q1 SOIL SCIENCE

Soil Biology & Biochemistry

Pub Date : 2026-03-01 Epub Date: 2025-12-06 DOI: 10.1016/j.soilbio.2025.110055

Xin Guo , Meng Wang

Vascular plant encroachment at the expense of Sphagnum mosses may threaten peatland carbon (C) stocks, yet the role of plant functional types (PFTs) and their fungal partners remains unclear. We conducted an in situ clipping experiment in a montane peatland to examine how shrubs, graminoids, and Sphagnum mosses shape fungal abundance, diversity, and functional composition across acrotelm (0–20 cm) and mesotelm (20–30 cm) layers. Shrub clipping reduced overall fungal diversity and the relative abundances of ericoid (ErMF) and ectomycorrhizal fungi (EcMF) in the acrotelm, while increasing the relative abundance of lignocellulose-degrading fungi. In contrast, arbuscular mycorrhizal fungi (AMF) were less abundant than ErMF and EcMF, and responded primarily to edaphic conditions, especially low phosphate availability. Although the relative abundance of Sphagnum-associated fungi increased with Sphagnum cover, their distribution was mainly governed by temperature rather than host abundance. Notably, shrub encroachment may enhance peatland C stocks by increasing plant–fungal C inputs and suppressing decomposition, partially counteracting climate-driven C losses. By disentangling PFT and depth effects, this study demonstrates that shrub clipping selectively alters mycorrhizal and saprotrophic fungi in surface peat, whereas AMF respond mainly to edaphic variation. This depth-dependent decoupling between host and edaphic controls provides new insight into how vegetation change restructures fungal networks and regulates peatland C dynamics.

以泥炭藓为代价的维管植物入侵可能威胁泥炭地碳(C)储量，但植物功能类型（pft）及其真菌伙伴的作用尚不清楚。作者在山地泥炭地进行了原位剪枝实验，研究了灌木、禾本科植物和泥炭藓类植物在肢端层（0-20 cm）和中端层（20-30 cm）真菌丰度、多样性和功能组成的变化。灌木修剪降低了叶柄部真菌的总体多样性和叶柄类真菌（ErMF）和外生菌根真菌（EcMF）的相对丰度，而增加了木质纤维素降解真菌的相对丰度。相比之下，丛枝菌根真菌（AMF）的丰度低于ErMF和EcMF，并且主要对土壤条件，特别是低磷酸盐有效性做出反应。虽然藓类相关真菌的相对丰度随着藓类覆盖的增加而增加，但其分布主要受温度而非宿主丰度的影响。值得注意的是，灌木入侵可能通过增加植物真菌C输入和抑制分解来增加泥炭地C储量，部分抵消气候驱动的C损失。通过分离PFT和深度效应，本研究表明灌木修剪选择性地改变了表层泥炭的菌根真菌和腐养真菌，而AMF主要响应土壤变化。宿主和土壤控制之间的深度依赖解耦为植被变化如何重构真菌网络和调节泥炭地C动态提供了新的见解。

{"title":"Belowground perspectives: how plant functional type clipping reshapes soil fungal communities across peat depths","authors":"Xin Guo , Meng Wang","doi":"10.1016/j.soilbio.2025.110055","DOIUrl":"10.1016/j.soilbio.2025.110055","url":null,"abstract":"<div><div>Vascular plant encroachment at the expense of <em>Sphagnum</em> mosses may threaten peatland carbon (C) stocks, yet the role of plant functional types (PFTs) and their fungal partners remains unclear. We conducted an <em>in situ</em> clipping experiment in a montane peatland to examine how shrubs, graminoids, and <em>Sphagnum</em> mosses shape fungal abundance, diversity, and functional composition across acrotelm (0–20 cm) and mesotelm (20–30 cm) layers. Shrub clipping reduced overall fungal diversity and the relative abundances of ericoid (ErMF) and ectomycorrhizal fungi (EcMF) in the acrotelm, while increasing the relative abundance of lignocellulose-degrading fungi. In contrast, arbuscular mycorrhizal fungi (AMF) were less abundant than ErMF and EcMF, and responded primarily to edaphic conditions, especially low phosphate availability. Although the relative abundance of <em>Sphagnum</em>-associated fungi increased with <em>Sphagnum</em> cover, their distribution was mainly governed by temperature rather than host abundance. Notably, shrub encroachment may enhance peatland C stocks by increasing plant–fungal C inputs and suppressing decomposition, partially counteracting climate-driven C losses. By disentangling PFT and depth effects, this study demonstrates that shrub clipping selectively alters mycorrhizal and saprotrophic fungi in surface peat, whereas AMF respond mainly to edaphic variation. This depth-dependent decoupling between host and edaphic controls provides new insight into how vegetation change restructures fungal networks and regulates peatland C dynamics.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"214 ","pages":"Article 110055"},"PeriodicalIF":10.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145689064","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Microbial community regulation of extracellular enzyme production can mediate patterns of particulate and mineral-associated organic matter accumulation in undersaturated soils 微生物群落对胞外酶生产的调节可以介导欠饱和土壤中颗粒和矿物相关有机质的积累模式

IF 10.3 1区农林科学 Q1 SOIL SCIENCE

Soil Biology & Biochemistry

Pub Date : 2026-03-01 Epub Date: 2025-12-04 DOI: 10.1016/j.soilbio.2025.110056

Paige M. Hansen , Yao Zhang , Ksenia Guseva , Christina Kaiser , M. Francesca Cotrufo

Dissolved low molecular weight (LMW) compounds in soil can either be assimilated by microbes or sorb onto mineral surfaces, forming mineral-associated organic matter (MAOM). This creates possible ‘competition’ between microbes and mineral surfaces for LMW compounds, potentially influencing whether particulate organic matter (POM) is retained or depolymerized by microbes to produce LMW substrates. Therefore, microscale interactions between unoccupied mineral surfaces and microbial enzymes may mediate patterns of POM and MAOM storage, particularly in soils varying in MAOM saturation. To explore this, we adapted an individual-based microscale model to simulate POM retention and new MAOM formation under different initial POM qualities (carbon:nitrogen ratio; C:N) and MAOM saturation levels, while also considering microbial social-like dynamics, which emerge from interactions between microbes with different capacities to produce and share public goods (in this case, extracellular enzymes). Consistent with prior findings, the presence of these dynamics slowed decomposition of initial POM pools, particularly at high C:N ratios. Additionally, MAOM saturation affected microbial community properties, MAOM formation, and POM decomposition in ways that depended on POM C:N, but only when social dynamics were included. The patterns of POM decomposition and MAOM formation identified in our work align with observations of simultaneous POM and MAOM formation in undersaturated soils from prior field studies, suggesting that regulation of enzyme production via microbial interactions may be an additional driver of POM and MAOM storage in such soils. Overall, this highlights the importance of explicitly incorporating microbial ecology into our conceptual understanding of C and N cycling, particularly to improve the predictive capacity of ecosystem models and inform soil management strategies that enhance global change mitigation, especially in degraded soils likely to be undersaturated.

土壤中溶解的低分子量（LMW）化合物既可以被微生物吸收，也可以吸附在矿物表面，形成矿物相关有机质（MAOM）。这可能会在微生物和矿物表面之间形成争夺低分子量化合物的“竞争”，从而潜在地影响颗粒有机物质（POM）是否被微生物保留或解聚以产生低分子量化合物底物。因此，未被占用的矿物表面与微生物酶之间的微尺度相互作用可能介导POM和MAOM储存模式，特别是在MAOM饱和度不同的土壤中。为了探索这一点，我们采用了一个基于个体的微尺度模型来模拟不同初始POM质量（碳氮比；C:N）和MAOM饱和水平下POM的保留和新MAOM的形成，同时也考虑了微生物类社会动力学，这是由具有不同生产和共享公共产品能力的微生物（在这种情况下是细胞外酶）之间的相互作用产生的。与先前的发现一致，这些动态的存在减缓了初始POM池的分解，特别是在高碳氮比下。此外，MAOM饱和度影响微生物群落特性、MAOM形成和POM分解的方式取决于POM C:N，但仅在包括社会动态的情况下。在我们的工作中发现的POM分解和MAOM形成的模式与之前在不饱和土壤中同时形成的POM和MAOM的观察结果一致，这表明通过微生物相互作用调节酶的产生可能是POM和MAOM在这些土壤中储存的另一个驱动因素。总的来说，这突出了将微生物生态学明确纳入我们对C和N循环的概念理解的重要性，特别是为了提高生态系统模型的预测能力，并为加强全球变化缓解的土壤管理战略提供信息，特别是在可能不饱和的退化土壤中。

{"title":"Microbial community regulation of extracellular enzyme production can mediate patterns of particulate and mineral-associated organic matter accumulation in undersaturated soils","authors":"Paige M. Hansen , Yao Zhang , Ksenia Guseva , Christina Kaiser , M. Francesca Cotrufo","doi":"10.1016/j.soilbio.2025.110056","DOIUrl":"10.1016/j.soilbio.2025.110056","url":null,"abstract":"<div><div>Dissolved low molecular weight (LMW) compounds in soil can either be assimilated by microbes or sorb onto mineral surfaces, forming mineral-associated organic matter (MAOM). This creates possible ‘competition’ between microbes and mineral surfaces for LMW compounds, potentially influencing whether particulate organic matter (POM) is retained or depolymerized by microbes to produce LMW substrates. Therefore, microscale interactions between unoccupied mineral surfaces and microbial enzymes may mediate patterns of POM and MAOM storage, particularly in soils varying in MAOM saturation. To explore this, we adapted an individual-based microscale model to simulate POM retention and new MAOM formation under different initial POM qualities (carbon:nitrogen ratio; C:N) and MAOM saturation levels, while also considering microbial social-like dynamics, which emerge from interactions between microbes with different capacities to produce and share public goods (in this case, extracellular enzymes). Consistent with prior findings, the presence of these dynamics slowed decomposition of initial POM pools, particularly at high C:N ratios. Additionally, MAOM saturation affected microbial community properties, MAOM formation, and POM decomposition in ways that depended on POM C:N, but only when social dynamics were included. The patterns of POM decomposition and MAOM formation identified in our work align with observations of simultaneous POM and MAOM formation in undersaturated soils from prior field studies, suggesting that regulation of enzyme production via microbial interactions may be an additional driver of POM and MAOM storage in such soils. Overall, this highlights the importance of explicitly incorporating microbial ecology into our conceptual understanding of C and N cycling, particularly to improve the predictive capacity of ecosystem models and inform soil management strategies that enhance global change mitigation, especially in degraded soils likely to be undersaturated.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"214 ","pages":"Article 110056"},"PeriodicalIF":10.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145689059","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Pyocyanin induces rice benzoxazinoid synthesis to co-drive cadmium immobilization in rhizosphere microdomain: Microbial metabolite-mediated spatiotemporal communication mechanisms 花青素诱导水稻苯并恶嗪合成协同驱动根际微域镉的固定化：微生物代谢物介导的时空通讯机制

IF 10.3 1区农林科学 Q1 SOIL SCIENCE

Soil Biology & Biochemistry

Pub Date : 2026-03-01 Epub Date: 2025-12-30 DOI: 10.1016/j.soilbio.2025.110081

Shengwei Yi , Zan Tian , Lanlan Wei , Feng Li , Lizhong Zhu , Fangbai Li , Songxiong Zhong , Fei Ge , Na Liu , Xionghui Ji , Jiang Tian , Yujun Wu

Microbial metabolites and root exudates significantly influence the fate of cadmium (Cd) in rhizosphere microdomains, but its interactions and regulatory mechanisms during the rice and microbiome dialogue remain poorly understood. Therefore, pyocyanin (PYO), a phenazine compound with redox properties secreted by Pseudomonas aeruginosa, was added to the rice rhizosphere microdomains. Subsequently, the response mechanisms of rice root exudates, rhizosphere microbiome, and Cd transformation were investigated using rice transcriptomics, metabolomics, and high-throughput 16S rRNA gene sequencing. The results indicated that PYO enhanced the biosynthesis of benzoxazinoids (BXs) and their intermediates by 1.2–2.0-fold in rice roots, thereby increasing the total accumulation of Cd in the roots through chelation. In turn, PYO and BXs reshaped functional rhizobacterial communities centered around Nitrospira, Kaistobacter, and Rubrivivax, which have potential Cd tolerance and adsorption capabilities. Consequently, the overall Cd adsorption by the rhizosphere microbial community increased significantly by 56.2 %–66.1 %. Pot experiments demonstrated that after the addition of PYO, the Cd bioavailability in the rhizosphere soil decreased by 5.6 %–27.5 %, and the translocation capacity of Cd from roots to shoot tissues was reduced by 15.4 %–46.0 %. Moreover, the application of PYO improved the catalase activity and the availability of major nutrients (nitrogen, phosphorus, and potassium) in the lightly contaminated soil during the jointing stage. The findings enhance the understanding of how microbial metabolites regulate rice root exudates to co-alleviate heavy metal toxicity and accumulation, thereby providing a theoretical basis for the development of biological prevention and control technologies for Cd in paddy soils.

微生物代谢物和根系分泌物显著影响水稻根际微域镉（Cd）的命运，但其在水稻与微生物组对话中的相互作用和调节机制尚不清楚。因此，将铜绿假单胞菌分泌的具有氧化还原特性的非那嗪类化合物pyocyanin （PYO）添加到水稻根际微域。随后，利用水稻转录组学、代谢组学和高通量16S rRNA基因测序研究了水稻根系分泌物、根际微生物组和Cd转化的响应机制。结果表明，PYO使苯并恶嗪类化合物（benzoxazinoids, BXs）及其中间体在水稻根系中的生物合成增加了1.2 ~ 2.0倍，从而通过螯合作用增加了根系中Cd的总积累。反过来，PYO和BXs重塑了以硝基螺旋菌、Kaistobacter和Rubrivivax为中心的功能性根瘤菌群落，这些根瘤菌具有潜在的Cd耐受性和吸附能力。因此，根际微生物群落对Cd的总体吸附量显著增加56.2% ~ 66.1%。盆栽试验表明，添加PYO后，根际土壤Cd生物有效性降低了5.6% ~ 27.5%，Cd从根到茎的转运能力降低了15.4% ~ 46.0%。此外，施用PYO提高了轻污染土壤在节育期过氧化氢酶活性和主要养分氮、磷、钾的有效性。研究结果有助于进一步认识微生物代谢物如何调控水稻根系分泌物，共同缓解重金属的毒性和积累，从而为开发水稻土Cd生物防治技术提供理论依据。

{"title":"Pyocyanin induces rice benzoxazinoid synthesis to co-drive cadmium immobilization in rhizosphere microdomain: Microbial metabolite-mediated spatiotemporal communication mechanisms","authors":"Shengwei Yi , Zan Tian , Lanlan Wei , Feng Li , Lizhong Zhu , Fangbai Li , Songxiong Zhong , Fei Ge , Na Liu , Xionghui Ji , Jiang Tian , Yujun Wu","doi":"10.1016/j.soilbio.2025.110081","DOIUrl":"10.1016/j.soilbio.2025.110081","url":null,"abstract":"<div><div>Microbial metabolites and root exudates significantly influence the fate of cadmium (Cd) in rhizosphere microdomains, but its interactions and regulatory mechanisms during the rice and microbiome dialogue remain poorly understood. Therefore, pyocyanin (PYO), a phenazine compound with redox properties secreted by <em>Pseudomonas aeruginosa</em>, was added to the rice rhizosphere microdomains. Subsequently, the response mechanisms of rice root exudates, rhizosphere microbiome, and Cd transformation were investigated using rice transcriptomics, metabolomics, and high-throughput 16S rRNA gene sequencing. The results indicated that PYO enhanced the biosynthesis of benzoxazinoids (BXs) and their intermediates by 1.2–2.0-fold in rice roots, thereby increasing the total accumulation of Cd in the roots through chelation. In turn, PYO and BXs reshaped functional rhizobacterial communities centered around <em>Nitrospira</em>, <em>Kaistobacter</em>, and <em>Rubrivivax</em>, which have potential Cd tolerance and adsorption capabilities. Consequently, the overall Cd adsorption by the rhizosphere microbial community increased significantly by 56.2 %–66.1 %. Pot experiments demonstrated that after the addition of PYO, the Cd bioavailability in the rhizosphere soil decreased by 5.6 %–27.5 %, and the translocation capacity of Cd from roots to shoot tissues was reduced by 15.4 %–46.0 %. Moreover, the application of PYO improved the catalase activity and the availability of major nutrients (nitrogen, phosphorus, and potassium) in the lightly contaminated soil during the jointing stage. The findings enhance the understanding of how microbial metabolites regulate rice root exudates to co-alleviate heavy metal toxicity and accumulation, thereby providing a theoretical basis for the development of biological prevention and control technologies for Cd in paddy soils.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"214 ","pages":"Article 110081"},"PeriodicalIF":10.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145884105","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0

Root tissue chemistry influences the formation and composition of new mineral-associated organic matter 根组织化学影响新矿物伴生有机质的形成和组成

IF 10.3 1区农林科学 Q1 SOIL SCIENCE

Soil Biology & Biochemistry

Pub Date : 2026-03-01 Epub Date: 2025-12-09 DOI: 10.1016/j.soilbio.2025.110064

Brian Rinehart , Joe P. Noel , Justin Allen , Joeri Kaal , Dave McNear , Hanna Poffenbarger

Interest in managing soil organic matter through plant inputs is increasing, but the role of plant litter chemistry in organic matter cycling is still debated. While roots are an important carbon input, there are conflicting findings on how root litter chemistry affects the formation and composition of organic matter across soil types. Roots of seven plant species with diverse chemical composition were incubated for six months in two soil types differing in texture and pH. Soil respiration was measured regularly and the movement of root carbon into soil organic matter fractions was tracked using carbon-13 natural abundance. In both soils, litters with high guaiacyl and syringyl lignin units had less respiration and less transformation of litter C into heavy particulate organic matter (POM) and mineral-associated organic matter (MAOM). High suberin content decreased respiration and increased the recovery of litter C in light POM, but had no effects on its transfer to heavy POM or MAOM. On the other hand, p-hydroxyphenyl lignin units had positive effects on the transformation of litter C into MAOM but limited effects on respiration or recovery of litter C in POM. The litter treatments had similar effects on litter-derived MAOM across both soils despite overall less litter C in that fraction for the coarse, low pH soil. We also found evidence of chemical changes to the MAOM, with the ratios of lignin subunits shifting towards the ratios found in the litters. Our results highlight that lignin composition, in addition to total amount, seems to shape decomposition dynamics. Our results also support the idea that microbial processing of high-quality litters facilitates stabilization of C in MAOM. However, we show that regardless of degradability roots leave a chemical imprint on MAOM, particularly through their lignin composition, suggesting that direct contributions of plant C to MAOM cannot be overlooked.

通过植物输入管理土壤有机质的兴趣日益增加，但植物凋落物化学在有机质循环中的作用仍存在争议。虽然根系是一个重要的碳输入，但关于根系凋落物化学如何影响不同土壤类型有机质的形成和组成，研究结果相互矛盾。采用不同化学成分的7种植物根系在不同质地和ph的2种土壤类型中培养6个月，定期测量土壤呼吸，利用碳-13自然丰度跟踪根系碳向土壤有机质组分的运动。在这两种土壤中，愈创木酰和丁香基木质素单位高的凋落物呼吸较少，凋落物C向重颗粒有机质（POM）和矿物相关有机质（MAOM）的转化较少。高亚木质素含量降低了轻POM中凋落物C的呼吸作用，增加了凋落物C的恢复，但对其向重POM或MAOM的转移没有影响。另一方面，对羟基苯基木质素单位对凋落物C转化为MAOM有积极作用，但对POM中凋落物C的呼吸或回收作用有限。在两种土壤中，凋落物处理对凋落物来源的MAOM有相似的影响，尽管粗、低pH土壤的凋落物C总体较少。我们还发现了MAOM化学变化的证据，木质素亚单位的比例向凋落物中的比例转移。我们的结果强调木质素组成，除了总量，似乎塑造分解动力学。我们的研究结果也支持了微生物处理高质量凋落物有助于MAOM中C稳定的观点。然而，我们表明，无论降解性如何，根系都会在MAOM上留下化学印记，特别是通过它们的木质素组成，这表明植物C对MAOM的直接贡献不容忽视。

{"title":"Root tissue chemistry influences the formation and composition of new mineral-associated organic matter","authors":"Brian Rinehart , Joe P. Noel , Justin Allen , Joeri Kaal , Dave McNear , Hanna Poffenbarger","doi":"10.1016/j.soilbio.2025.110064","DOIUrl":"10.1016/j.soilbio.2025.110064","url":null,"abstract":"<div><div>Interest in managing soil organic matter through plant inputs is increasing, but the role of plant litter chemistry in organic matter cycling is still debated. While roots are an important carbon input, there are conflicting findings on how root litter chemistry affects the formation and composition of organic matter across soil types. Roots of seven plant species with diverse chemical composition were incubated for six months in two soil types differing in texture and pH. Soil respiration was measured regularly and the movement of root carbon into soil organic matter fractions was tracked using carbon-13 natural abundance. In both soils, litters with high guaiacyl and syringyl lignin units had less respiration and less transformation of litter C into heavy particulate organic matter (POM) and mineral-associated organic matter (MAOM). High suberin content decreased respiration and increased the recovery of litter C in light POM, but had no effects on its transfer to heavy POM or MAOM. On the other hand, <em>p</em>-hydroxyphenyl lignin units had positive effects on the transformation of litter C into MAOM but limited effects on respiration or recovery of litter C in POM. The litter treatments had similar effects on litter-derived MAOM across both soils despite overall less litter C in that fraction for the coarse, low pH soil. We also found evidence of chemical changes to the MAOM, with the ratios of lignin subunits shifting towards the ratios found in the litters. Our results highlight that lignin composition, in addition to total amount, seems to shape decomposition dynamics. Our results also support the idea that microbial processing of high-quality litters facilitates stabilization of C in MAOM. However, we show that regardless of degradability roots leave a chemical imprint on MAOM, particularly through their lignin composition, suggesting that direct contributions of plant C to MAOM cannot be overlooked.</div></div>","PeriodicalId":21888,"journal":{"name":"Soil Biology & Biochemistry","volume":"214 ","pages":"Article 110064"},"PeriodicalIF":10.3,"publicationDate":"2026-03-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"145728778","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":1,"RegionCategory":"农林科学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

引用次数: 0