1
|
Liu L, Qin S, Richard Whalley W, Zhou H, Ren T, Gao W. The pore-rhizosheath shapes maize root architecture by enhancing root distribution in macropores. PLANT, CELL & ENVIRONMENT 2024; 47:2911-2922. [PMID: 38623641 DOI: 10.1111/pce.14915] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/28/2023] [Revised: 04/03/2024] [Accepted: 04/05/2024] [Indexed: 04/17/2024]
Abstract
Pores and old root-channels are preferentially used by roots to allow them to penetrate hard soils. However, there are few studies that have accounted for the effects of pore-rhizosheath on root growth. In this study, we developed an approach by adding the synthetic root exudates using a porous stainless tube with 0.1-mm micropores through a peristaltic pump to reproduce the rhizosheath around the artificial pore, and investigated the effects of pores with and without rhizosheaths on maize root growth in a dense soil. The results indicated that the artificial rhizosheath was about 2.69 mm wide in the region surrounding the pores. The rhizosheath had a higher content of organic carbon, total nitrogen, and abundance of Actinobacteria than that of the bulk soil. Compared with the artificial macropores, the artificial root-pores with a rhizosheath increased the opportunities for root utilisation of the pores space, promoting steeper and deeper root growth. It is concluded that the pore-rhizosheath has a significant impact on root architecture by enhancing root distribution in macropores.
Collapse
Affiliation(s)
- Lingling Liu
- College of Land Science and Technology, China Agricultural University, Beijing, China
| | - Shijie Qin
- College of Land Science and Technology, China Agricultural University, Beijing, China
| | | | - Hu Zhou
- College of Land Science and Technology, China Agricultural University, Beijing, China
| | - Tusheng Ren
- College of Land Science and Technology, China Agricultural University, Beijing, China
| | - Weida Gao
- College of Land Science and Technology, China Agricultural University, Beijing, China
| |
Collapse
|
2
|
Li C, Ma X, Wang Y, Sun Q, Chen M, Zhang C, Ding S, Dai Z. Root-mediated acidification, phosphatase activity and the phosphorus-cycling microbial community enhance phosphorus mobilization in the rhizosphere of wetland plants. WATER RESEARCH 2024; 255:121548. [PMID: 38569357 DOI: 10.1016/j.watres.2024.121548] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/11/2023] [Revised: 03/23/2024] [Accepted: 03/28/2024] [Indexed: 04/05/2024]
Abstract
Rhizoremediation of wetland plants is an environmentally friendly strategy for sediment phosphorous (P) removal, the basic underlying principle of which is the complex interactions between roots and microorganisms. This study investigated the immobilization and mobilization mechanisms of P in the rhizosphere of wetland plants using high-resolution spatial visualization techniques and metagenomic sequencing. Two-dimensional visualization of the spatial distribution of P, iron (Fe) and manganese (Mn) indicated that the sequestration of Fe-oxides rather than Mn-oxides caused the depletion of labile P, resulting in an increase in the Fe-adsorbed P fraction. Plants altered the rhizospheric environments and P-cycling microbial community to mobilize low-availability P from sediments. Mineral P solubilization and organic P mineralization were enhanced by local acidification and increased phosphatase activity, respectively. Microbial P mobilization also increased with increasing relative abundances of P solubilization and mineralization genes (gcd and phnW) and decreasing P transportation genes (ugpA, ugpB, and pit) genes in the rhizosphere. These processes led to the remobilization of 10.04 % of inorganic P, and 15.23 % of organic P, in the rhizosphere during the incubation period. However, the resupply of P via the above processes did not compensate for the depletion of rhizospheric P via root uptake and mineral sequestration. Our results provide novel insights into the mechanisms of rhizospheric P cycling, which will help to inform future phytoremediation strategies.
Collapse
Affiliation(s)
- Cai Li
- State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing Institute of Geography and Limnology, Nanjing 210008, China
| | - Xin Ma
- School of Hydrology and Water Resources, Hohai University, Nanjing 210098, China
| | - Yan Wang
- Ministry of Ecology and Environment, Nanjing Institute of Environmental Sciences, Nanjing 210042, China
| | - Qin Sun
- College of Environment, Hohai University, Nanjing 210098, China
| | - Musong Chen
- State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing Institute of Geography and Limnology, Nanjing 210008, China
| | - Chaosheng Zhang
- International Network for Environment and Health, School of Geography and Archaeology, National University of Ireland, Galway, Ireland
| | - Shiming Ding
- State Key Laboratory of Lake Science and Environment, Chinese Academy of Sciences, Nanjing Institute of Geography and Limnology, Nanjing 210008, China.
| | - Zhihui Dai
- State Key Laboratory of Ore Deposit Geochemistry, Chinese Academy of Sciences, Institute of Geochemistry, Guiyang 550081, China.
| |
Collapse
|
3
|
Li XY, Li XY, Jiang YF, Zhang C, Yang Q, Manzoor M, Luo J, Guan DX. High-resolution chemical imaging to understand Cd activation in rice rhizosphere of karstic soils. CHEMOSPHERE 2024; 349:140988. [PMID: 38122945 DOI: 10.1016/j.chemosphere.2023.140988] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/04/2023] [Revised: 12/09/2023] [Accepted: 12/16/2023] [Indexed: 12/23/2023]
Abstract
Cadmium (Cd) activation, especially at a high spatial resolution, in paddy soils with a high geogenic Cd background is yet to be understood. To investigate the temporal and spatial patterns of Cd activation in rice rhizosphere, pot and rhizotron experiments were conducted using four paddy soils with high geogenic Cd (0.11-3.70 mg kg-1) from Guangxi, southwestern China. The pot experiment results showed that porewater Cd concentrations initially decreased and then increased over the complete rice growth period, reaching its lowest value during the late-tillering and early-filling stages. Besides, correlation analysis identified organic matter and root manganese (Mn) content as the main factors affecting rice Cd uptake, with Mn having a negative effect and organic matter having a positive effect. Sub-millimeter two-dimensional chemical imaging revealed that the distribution of labile Cd in the rhizosphere (by diffusive gradients in thin-films, or DGT) was influenced by the root system and soil properties, such as pH (by planar optode) and acid phosphatase activity (by soil zymography). Soil acid phosphatase activity increased under Cd stress. The overall pH at rice rhizosphere decreased. Moreover, a close relationship was found between the spatial distributions of soil labile Mn and Cd at the rhizosphere, with higher Mn being associated with lower Cd lability. This study highlights Mn as a key element in regulating rice Cd uptake and enlightens future Mn-based strategies for addressing Cd pollution in rice paddy soils, especially in karst areas with high geochemical background.
Collapse
Affiliation(s)
- Xing-Yue Li
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Xi-Yuan Li
- Tianjin Key Laboratory of Earth Critical Zone Science and Sustainable Development in Bohai Rim, Institute of Surface-Earth System Science, School of Earth System Science, Tianjin University, Tianjin, 300072, China
| | - Yi-Fan Jiang
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Chao Zhang
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Qiong Yang
- School of Agricultural Sciences, Zhengzhou University, Zhengzhou, 450001, China
| | - Maria Manzoor
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China
| | - Jun Luo
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Nanjing, 210023, China
| | - Dong-Xing Guan
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
| |
Collapse
|
4
|
Bornø ML, Zervas A, Bak F, Merl T, Koren K, Nicolaisen MH, Jensen LS, Müller-Stöver DS. Differential impacts of sewage sludge and biochar on phosphorus-related processes: An imaging study of the rhizosphere. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 905:166888. [PMID: 37730064 DOI: 10.1016/j.scitotenv.2023.166888] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/23/2023] [Revised: 08/15/2023] [Accepted: 09/05/2023] [Indexed: 09/22/2023]
Abstract
Recycling of phosphorus (P) from waste streams in agriculture is essential to reduce the negative environmental effects of surplus P and the unsustainable mining of geological P resources. Sewage sludge (SS) is an important P source; however, several issues are associated with the handling and application of SS in agriculture. Thus, post-treatments such as pyrolysis of SS into biochar (BC) could address some of these issues. Here we elucidate how patches of SS in soil interact with the living roots of wheat and affect important P-related rhizosphere processes compared to their BC counterparts. Wheat plants were grown in rhizoboxes with sandy loam soil, and 1 cm Ø patches with either SS or BC placed 10 cm below the seed. A negative control (CK) was included. Planar optode pH sensors were used to visualize spatiotemporal pH changes during 40 days of plant growth, diffusive gradients in thin films (DGT) were applied to map labile P, and zymography was used to visualize the spatial distribution of acid (ACP) and alkaline (ALP) phosphatase activity. In addition, bulk soil measurements of available P, pH, and ACP activity were conducted. Finally, the relative abundance of bacterial P-cycling genes (phoD, phoX, phnK) was determined in the patch area rhizosphere. Labile P was only observed in the area of the SS patches, and SS further triggered root proliferation and increased the activity of ACP and ALP in interaction with the roots. In contrast, BC seemed to be inert, had no visible effect on root growth, and even reduced ACP and ALP activity in the patch area. Furthermore, there was a lower relative abundance of phoD and phnK genes in the BC rhizosphere compared to the CK. Hence, optimization of BC properties is needed to increase the short-term efficiency of BC from SS as a P fertilizer.
Collapse
Affiliation(s)
- Marie Louise Bornø
- University of Copenhagen, Department of Plant & Environmental Sciences, Thorvaldsensvej 40, 1821 Frederiksberg, Denmark.
| | - Athanasios Zervas
- Aarhus University, Department of Environmental Science, Frederiksborgvej 399, 4000 Roskilde, Denmark
| | - Frederik Bak
- University of Copenhagen, Department of Plant & Environmental Sciences, Thorvaldsensvej 40, 1821 Frederiksberg, Denmark; Austrian Institute of Technology, Bioresources Unit, Konrad-Lorenz-Straße 24, 3430 Tulln, Austria
| | - Theresa Merl
- Aarhus University Centre for Water Technology, Department of Biology - Microbiology, Ny Munkegade 116, 8000 Aarhus C, Denmark
| | - Klaus Koren
- Aarhus University Centre for Water Technology, Department of Biology - Microbiology, Ny Munkegade 116, 8000 Aarhus C, Denmark
| | - Mette H Nicolaisen
- University of Copenhagen, Department of Plant & Environmental Sciences, Thorvaldsensvej 40, 1821 Frederiksberg, Denmark
| | - Lars S Jensen
- University of Copenhagen, Department of Plant & Environmental Sciences, Thorvaldsensvej 40, 1821 Frederiksberg, Denmark
| | - Dorette S Müller-Stöver
- University of Copenhagen, Department of Plant & Environmental Sciences, Thorvaldsensvej 40, 1821 Frederiksberg, Denmark
| |
Collapse
|
5
|
Lin J, Sun Y, Zhang H, Shen Q, Xu L, Zeng Q, Su Y, Han C. Two-dimensional, high-resolution imaging of pH dynamics in the phyllosphere of submerged macrophyte using a new Nano-optode. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 903:166327. [PMID: 37595908 DOI: 10.1016/j.scitotenv.2023.166327] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/04/2023] [Revised: 08/11/2023] [Accepted: 08/13/2023] [Indexed: 08/20/2023]
Abstract
The phyllosphere pH helps shape the plant microbiome and strongly influences aboveground interactions in plant canopies. Yet little is known about the distribution of pH at a microscale within the macrophyte phyllosphere and the factors promoting them because achieving high-resolution quantitative imaging of phyllosphere pH is a great challenge. Here, new ratiometric pH nano-optodes were prepared by firstly encapsulating the self-synthesized lipophilic dyes (8-acetoxypyrene-N1, N3, N6-trioctadecyl-1, 3, 6-tri-trisulfonamide) to poly(1-vinylpyrrolidone-co-styrene) nanoparticles, and then immobilizing the resulting nanoparticles in polyurethane hydrogel on transparent foils. The nano-optodes presented reversible and fast response (t95 < 80 s) to the pH range from 7.0 to 11.0, with merits of good spatial resolution, photobleaching/leaching resistance and negligible cross-sensitives toward temperature, O2 and ionic strength (< 100 mM). The nano-optodes together with a self-designed phyllosphere chamber were further applied to directly measure the pH distributions at a microscale around single leaves of V. spiralis grown in natural sediment. The pronounced pH microheterogeneity and leaf basification within the V. spiralis phyllosphere were quantitatively visualized. We also provided direct empirical evidence that the dynamic of the phyllosphere pH at high resolution was significantly controlled by the shifting light intensity and temperature. Implementation of the nano-optodes holds great potential for various laboratory applications, which will provide an in-depth insight into phyllosphere activities on the microscale.
Collapse
Affiliation(s)
- Jianyu Lin
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Yu Sun
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Hao Zhang
- Lancaster Environment Centre, Lancaster University, Lancaster LA1 4YQ, UK
| | - Qiushi Shen
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Li Xu
- Institute of Quality Standard and Testing Technology, Beijing Academy of Agriculture and Forestry Sciences, Beijing 100097, China
| | - Qingfei Zeng
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Yaling Su
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Chao Han
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
| |
Collapse
|
6
|
Zhou F, Liu Y, Xie W, Huang J, Liu F, Kong W, Zhao Z, Peng J. Recent advances and applications of laser-based imaging techniques in food crops and products: a critical review. Crit Rev Food Sci Nutr 2023:1-17. [PMID: 37983168 DOI: 10.1080/10408398.2023.2283579] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2023]
Abstract
To meet the growing demand for food quality and safety, there is a pressing need for fast and visible techniques to monitor the food crop and product production processing, and to understand the chemical changes that occur during these processes. Herein, the fundamental principles, instruments, and characteristics of three major laser-based imaging techniques (LBITs), namely, laser-induced breakdown spectroscopy, Raman spectroscopy, and laser ablation-inductively coupled plasma-mass spectrometry, are introduced. Additionally, the advances, challenges, and prospects for the application of LBITs in food crops and products are discussed. In recent years, LBITs have played a crucial role in mapping primary metabolites, secondary metabolites, nanoparticles, toxic metals, and mineral elements in food crops, as well as visualizing food adulteration, composition changes, pesticide residue, microbial contamination, and elements in food products. However, LBITs are still facing challenges in achieving accurate and sensitive quantification of compositions due to the complex sample matrix and minimal laser sampling quantity. Thus, further research is required to develop comprehensive data processing strategies and signal enhancement methods. With the continued development of imaging methods and equipment, LBITs have the potential to further explore chemical distribution mechanisms and ensure the safety and quality of food crops and products.
Collapse
Affiliation(s)
- Fei Zhou
- College of Standardization, China Jiliang University, Hangzhou, China
- College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Yifan Liu
- College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Weiyue Xie
- College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Jing Huang
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
| | - Fei Liu
- College of Biosystems Engineering and Food Science, Zhejiang University, Hangzhou, China
| | - Wenwen Kong
- College of Mathematics and Computer Science, Zhejiang A & F University, Hangzhou, China
| | - Zhangfeng Zhao
- College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, China
| | - Jiyu Peng
- College of Mechanical Engineering, Zhejiang University of Technology, Hangzhou, China
| |
Collapse
|
7
|
Hummel C, Daudin G, Gerzabek MH, Santner J, Wenzel WW, Oburger E. Chemical imaging reveals environmental risk of minor tungsten and lead shotgun pellet constituents during weathering in soil. THE SCIENCE OF THE TOTAL ENVIRONMENT 2023; 882:163554. [PMID: 37088395 DOI: 10.1016/j.scitotenv.2023.163554] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/14/2023] [Revised: 04/13/2023] [Accepted: 04/13/2023] [Indexed: 05/03/2023]
Abstract
Tungsten (W)-based shots are considered more environmentally safe than lead (Pb)-based shots, but knowledge about the W-shot fate in the soil environment is still limited, especially in terms of minor constituents such as iron, copper, and nickel (Ni). Contaminant behaviour in soil strongly depends on pH; in turn, the corrosion of metal composites may affect the pH locally. The aim of this study was to compare Pb- and W-shot weathering dynamics in soil (silt loam, pH 6.3) and reveal the interplay of shot weathering-induced pH-changes on the mobility of elements using in situ chemical imaging (Diffusive gradients in thin films for labile elements, planar optodes for soil pH) and batch incubation experiments over time (16 months). Despite our expectation to find acidification due to W oxidation, we observed a pH increase by 0.2 units in extracted soil solutions and by 0.6 units in the soil around W-shots as Ni dissolved from the binder phase of the shot. After 10 weeks, release of labile Ni was 3-times higher compared to W despite the low Ni content in the shot (7 %, m/m). Pb-shot oxidation increased soil solution pH by 0.5 units which likely supported mobility of Pb-shot-derived antimony (Sb). Steep gradients of labile W and Pb and soil solution concentrations <0.8 μmol L-1 indicated that transfer from shot to soil was low. Contrastingly, labile Ni and Sb were found up to ~4 mm from the shot surface and in higher soil solution concentrations as suggested by the shot constitution, indicating higher mobility of minor as compared to major shot constituents. After 16 months, 36 % of total Ni were dissolved in the soil solution highlighting the environmental relevance of minor shot constituents in Pb-shot alternatives after short term weathering in soil.
Collapse
Affiliation(s)
- Christina Hummel
- University of Natural Resources and Life Sciences, BOKU, Department of Forest and Soil Sciences, Institute of Soil Research, Konrad-Lorenz Strasse 24, A-3430 Tulln, Austria
| | - Gabrielle Daudin
- Eco&Sols, Univ Montpellier, CIRAD, INRAE, IRD, Institut Agro, 2 place Viala, F-34060 Montpellier, France
| | - Martin H Gerzabek
- University of Natural Resources and Life Sciences, BOKU, Department of Forest and Soil Sciences, Institute of Soil Research, Peter-Jordan-Straße 82, A-1190 Vienna, Austria
| | - Jakob Santner
- University of Natural Resources and Life Sciences, BOKU, Institute of Agronomy, Konrad-Lorenz Strasse 24, A-3430 Tulln, Austria; Justus-Liebig-University Giessen, Institute of Plant Nutrition, Heinrich-Buff-Ring 26-32, 35390 Gießen, Germany
| | - Walter W Wenzel
- University of Natural Resources and Life Sciences, BOKU, Department of Forest and Soil Sciences, Institute of Soil Research, Konrad-Lorenz Strasse 24, A-3430 Tulln, Austria
| | - Eva Oburger
- University of Natural Resources and Life Sciences, BOKU, Department of Forest and Soil Sciences, Institute of Soil Research, Konrad-Lorenz Strasse 24, A-3430 Tulln, Austria.
| |
Collapse
|
8
|
Stimulation of Distinct Rhizosphere Bacteria Drives Phosphorus and Nitrogen Mineralization in Oilseed Rape under Field Conditions. mSystems 2022; 7:e0002522. [PMID: 35862821 PMCID: PMC9426549 DOI: 10.1128/msystems.00025-22] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/04/2023] Open
Abstract
Advances in DNA sequencing technologies have drastically changed our perception of the structure and complexity of the plant microbiome. By comparison, our ability to accurately identify the metabolically active fraction of soil microbiota and its specific functional role in augmenting plant health is relatively limited. Important ecological interactions being performed by microbes can be investigated by analyzing the extracellular protein fraction. Here, we combined a unique protein extraction method and an iterative bioinformatics pipeline to capture and identify extracellular proteins (metaexoproteomics) synthesized in the rhizosphere of Brassica spp. We first validated our method in the laboratory by successfully identifying proteins related to a host plant (Brassica rapa) and its bacterial inoculant, Pseudomonas putida BIRD-1. This identified numerous rhizosphere specific proteins linked to the acquisition of plant-derived nutrients in P. putida. Next, we analyzed natural field-soil microbial communities associated with Brassica napus L. (oilseed rape). By combining metagenomics with metaexoproteomics, 1,885 plant, insect, and microbial proteins were identified across bulk and rhizosphere samples. Metaexoproteomics identified a significant shift in the metabolically active fraction of the soil microbiota responding to the presence of B. napus roots that was not apparent in the composition of the total microbial community (metagenome). This included stimulation of rhizosphere-specialized bacteria, such as Gammaproteobacteria, Betaproteobacteria, and Flavobacteriia, and the upregulation of plant beneficial functions related to phosphorus and nitrogen mineralization. Our metaproteomic assessment of the “active” plant microbiome at the field-scale demonstrates the importance of moving beyond metagenomics to determine ecologically important plant-microbe interactions underpinning plant health. IMPORTANCE Plant-microbe interactions are critical to ecosystem function and crop production. While significant advances have been made toward understanding the structure of the plant microbiome, learning about its full functional role is still in its infancy. This is primarily due to an incomplete ability to determine in situ plant-microbe interactions actively operating under field conditions. Proteins are the functional entities of the cell. Therefore, their identification and relative quantification within a microbial community provide the best proxy for which microbes are the most metabolically active and which are driving important plant-microbe interactions. Here, we provide the first metaexoproteomics assessment of the plant microbiome using field-grown oilseed rape as the model crop species, identifying key taxa responsible for specific ecological interactions. Gaining a mechanistic understanding of the plant microbiome is central to developing engineered plant microbiomes to improve sustainable agricultural approaches and reduce our reliance on nonrenewable resources.
Collapse
|
9
|
Stiblíková P, Klimeš A, Cahill JF, Koubek T, Weiser M. Interspecific differences in root foraging precision cannot be directly inferred from species' mycorrhizal status or fine root economics. OIKOS 2022. [DOI: 10.1111/oik.08995] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
| | - Adam Klimeš
- Dept of Functional Ecology, Inst. of Botany, Czech Academy of Sciences Třeboň Czechia
- Dept of Biological Sciences, Biological Sciences Building, Univ. of Alberta Edmonton AB Canada
| | - James F. Cahill
- Dept of Biological Sciences, Faculty of Mathematics and Natural Sciences, Univ. of Bergen Bergen Norway
| | - Tomáš Koubek
- Dept of Botany, Faculty of Science, Charles Univ. Praha Czechia
| | - Martin Weiser
- Dept of Botany, Faculty of Science, Charles Univ. Praha Czechia
| |
Collapse
|
10
|
Doolette CL, Howard DL, Afshar N, Kewish CM, Paterson DJ, Huang J, Wagner S, Santner J, Wenzel WW, Raimondo T, De Vries Van Leeuwen AT, Hou L, van der Bom F, Weng H, Kopittke PM, Lombi E. Tandem Probe Analysis Mode for Synchrotron XFM: Doubling Throughput Capacity. Anal Chem 2022; 94:4584-4593. [PMID: 35276040 PMCID: PMC8943523 DOI: 10.1021/acs.analchem.1c04255] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Synchrotron-based X-ray fluorescence microscopy (XFM) analysis is a powerful technique that can be used to visualize elemental distributions across a broad range of sample types. Compared to conventional mapping techniques such as laser ablation inductively coupled plasma mass spectrometry or benchtop XFM, synchrotron-based XFM provides faster and more sensitive analyses. However, access to synchrotron XFM beamlines is highly competitive, and as a result, these beamlines are often oversubscribed. Therefore, XFM experiments that require many large samples to be scanned can penalize beamline throughput. Our study was largely driven by the need to scan large gels (170 cm2) using XFM without decreasing beamline throughput. We describe a novel approach for acquiring two sets of XFM data using two fluorescence detectors in tandem; essentially performing two separate experiments simultaneously. We measured the effects of tandem scanning on beam quality by analyzing a range of contrasting samples downstream while simultaneously scanning different gel materials upstream. The upstream gels were thin (<200 μm) diffusive gradients in thin-film (DGT) binding gels. DGTs are passive samplers that are deployed in water, soil, and sediment to measure the concentration and distribution of potentially bioavailable nutrients and contaminants. When deployed on soil, DGTs are typically small (2.5 cm2), so we developed large DGTs (170 cm2), which can be used to provide extensive maps to visualize the diffusion of fertilizers in soil. Of the DGT gel materials tested (bis-acrylamide, polyacrylamide, and polyurethane), polyurethane gels were most suitable for XFM analysis, having favorable handling, drying, and analytical properties. This gel type enabled quantitative (>99%) transmittance with minimal (<3%) flux variation during raster scanning, whereas the other gels had a substantial effect on the beam focus. For the first time, we have (1) used XFM for mapping analytes in large DGTs and (2) developed a tandem probe analysis mode for synchrotron-based XFM, effectively doubling throughput. The novel tandem probe analysis mode described here is of broad applicability across many XFM beamlines as it could be used for future experiments where any uniform, highly transmissive sample could be analyzed upstream in the "background" of downstream samples.
Collapse
Affiliation(s)
- Casey L Doolette
- Future Industries Institutes, University of South Australia, Mawson Lakes, South Australia 5095, Australia
| | - Daryl L Howard
- Australian Synchrotron, ANSTO, Clayton, Victoria 3168, Australia
| | - Nader Afshar
- Australian Synchrotron, ANSTO, Clayton, Victoria 3168, Australia
| | - Cameron M Kewish
- Australian Synchrotron, ANSTO, Clayton, Victoria 3168, Australia.,Department of Chemistry and Physics, School of Molecular Sciences, La Trobe University, Melbourne, Victoria 3086, Australia
| | - David J Paterson
- Australian Synchrotron, ANSTO, Clayton, Victoria 3168, Australia
| | - Jianyin Huang
- Future Industries Institutes, University of South Australia, Mawson Lakes, South Australia 5095, Australia.,UniSA STEM, University of South Australia, Mawson Lakes, South Australia 5095, Australia
| | - Stefan Wagner
- Chair of General and Analytical Chemistry, Montanuniversität Leoben, Leoben 8700, Austria.,Institute of Analytical Chemistry, University of Natural Resources and Life Sciences Vienna, Tulln 3430, Austria.,Institute of Soil Research, University of Natural Resources and Life Sciences Vienna, Tulln 3430, Austria
| | - Jakob Santner
- Institute of Agronomy, University of Natural Resources and Life Sciences Vienna, Tulln 3430, Austria
| | - Walter W Wenzel
- Institute of Soil Research, University of Natural Resources and Life Sciences Vienna, Tulln 3430, Austria
| | - Tom Raimondo
- Future Industries Institutes, University of South Australia, Mawson Lakes, South Australia 5095, Australia.,UniSA STEM, University of South Australia, Mawson Lakes, South Australia 5095, Australia
| | | | - Lei Hou
- Future Industries Institutes, University of South Australia, Mawson Lakes, South Australia 5095, Australia.,The University of Queensland, School of Agriculture and Food Sciences, St Lucia, Queensland 4072, Australia
| | - Frederik van der Bom
- The University of Queensland, School of Agriculture and Food Sciences, St Lucia, Queensland 4072, Australia
| | - Han Weng
- The University of Queensland, School of Agriculture and Food Sciences, St Lucia, Queensland 4072, Australia
| | - Peter M Kopittke
- The University of Queensland, School of Agriculture and Food Sciences, St Lucia, Queensland 4072, Australia
| | - Enzo Lombi
- Future Industries Institutes, University of South Australia, Mawson Lakes, South Australia 5095, Australia.,UniSA STEM, University of South Australia, Mawson Lakes, South Australia 5095, Australia
| |
Collapse
|
11
|
Li C, Ding S, Chen M, Sun Q, Zhang Y, Ma X, Zhong Z, Tsang DCW, Wang Y. Mechanistic insights into trace metal mobilization at the micro-scale in the rhizosphere of Vallisneria spiralis. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 806:150735. [PMID: 34606867 DOI: 10.1016/j.scitotenv.2021.150735] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/23/2021] [Revised: 09/28/2021] [Accepted: 09/28/2021] [Indexed: 06/13/2023]
Abstract
Mobilization of trace metals in the rhizosphere of macrophytes is controlled by root-driven chemical changes, especially the steep gradients of O2 and pH from the rhizosphere to bulk sediments. Here, the O2 and pH dynamics, and the distribution of trace metal, in the rhizosphere of Vallisneria spiralis were obtained using planar optodes and diffusive gradients in thin films, respectively. Radial O2 loss (ROL) and acidification occurred on all visible roots of V. spiralis and exhibited highly spatiotemporal dynamics depending on the root growth and various environmental conditions. Trace metals showed different mobilization mechanisms in the rhizosphere. ROL and produced Fe(III) (oxyhydr)oxides decreased the mobility of Fe, As, Co, V and W in the rhizosphere. However, Mn, Ni and Cu exhibited greater mobility in the rhizosphere than bulk sediments as a result of the oxidation of metal sulfide and proton-induced dissolution of minerals. In particular, Co and Ni presented increased activity at the interface between rhizosphere and bulk sediment, which was attributed to the redox dissolution processes of Fe and Mn as a result of ROL and rhizosphere acidification. These results provide new insights into the roles of macrophyte root-induced O2 and pH changes in controlling trace metal mobility in sediments.
Collapse
Affiliation(s)
- Cai Li
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shiming Ding
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
| | - Musong Chen
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| | - Qin Sun
- College of Environment, Hohai University, Nanjing 210098, China
| | - Yi Zhang
- School of Hydrology and Water Resources, Hohai University, Nanjing 210098, China
| | - Xin Ma
- School of Hydrology and Water Resources, Hohai University, Nanjing 210098, China
| | - Zhilin Zhong
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
| | - Yan Wang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China
| |
Collapse
|
12
|
Comparison of methods for mapping rhizosphere processes in the context of their surrounding root and soil environments. Biotechniques 2021; 71:604-614. [PMID: 34809497 DOI: 10.2144/btn-2021-0021] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
The rhizosphere embodies a complex biogeochemical zone with enhanced rates of nutrient exchange between plants, soil, and microbial communities. Understanding controls on rhizosphere dynamics is critical to support emerging concepts including rhizosphere engineering and reduced dependence on chemical fertilizers which have direct application to food production, increased biofuel generation, and habitat restoration efforts. Yet, its fine spatial scale and complex interactions between geochemical and microbial processes within complex spatiotemporal gradients make the rhizosphere notoriously difficult to study. Emerging instrumentation and methodologies, however, are providing improved resolution to rhizosphere measurements and helping to address critical knowledge gaps in rhizosphere function, ecology, and establishment. Here, we examine recent advances in analysis techniques and the resulting potential for improved understanding of rhizosphere function.
Collapse
|
13
|
de Tombeur F, Cornelis JT, Lambers H. Silicon mobilisation by root-released carboxylates. TRENDS IN PLANT SCIENCE 2021; 26:1116-1125. [PMID: 34315662 DOI: 10.1016/j.tplants.2021.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/30/2021] [Accepted: 07/01/2021] [Indexed: 06/13/2023]
Abstract
Plants have evolved numerous strategies to acquire poorly available nutrients from soil, including the release of carboxylates from their roots. Silicon (Si) release from mineral dissolution increases in the presence of chelating substances, and recent evidence shows that leaf [Si] increases markedly in old phosphorus (P)-depleted soils, where many species exhibit carboxylate-releasing strategies, compared with younger P-richer soils. Here, we propose that root-released carboxylates, and more generally rhizosphere processes, play an overlooked role in plant Si accumulation by increasing soil Si mobilisation from minerals. We suggest that Si mobilisation is costly in terms of carbon but becomes cheaper if those costs are already met to acquire poorly available P. Uptake of the mobilised Si by roots will then depend on whether they express Si transporters.
Collapse
Affiliation(s)
- Félix de Tombeur
- TERRA Teaching and Research Centre, Gembloux Agro-Bio Tech, University of Liege, Gembloux, Belgium.
| | - Jean-Thomas Cornelis
- TERRA Teaching and Research Centre, Gembloux Agro-Bio Tech, University of Liege, Gembloux, Belgium; Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Hans Lambers
- School of Biological Sciences, The University of Western Australia, Crawley (Perth), WA 6009, Australia.
| |
Collapse
|
14
|
Ren M, Ding S, Dai Z, Wang J, Li C, Zhong Z, Cao J, Yang L, Tsang DCW, Xu S, Yang C, Wang Y. A new DGT technique comprising a hybrid sensor for the simultaneous high resolution 2-D imaging of sulfides, metallic cations, oxyanions and dissolved oxygen. JOURNAL OF HAZARDOUS MATERIALS 2021; 403:123597. [PMID: 32781278 DOI: 10.1016/j.jhazmat.2020.123597] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/06/2020] [Revised: 07/26/2020] [Accepted: 07/27/2020] [Indexed: 06/11/2023]
Abstract
A new diffusive gradients in thin films technique (HR-ZCA DGT) was developed for simultaneous two-dimensional (2-D) chemical imaging of sulfides, metallic cations and oxyanions (S, Cd, Co, Fe, Cu, Mn, Ni, Pb, Zn, As, Cr, Mo, Sb, Se, V, P and W) at the submillimeter scale, combined with laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) analysis. A novel binding gel was prepared using a double precipitation method with AgI and zirconium oxide (Zr-oxide) deposited sequentially on a preformed Chelex-100 resin gel. A good linear relationship was observed (R2>0.99) between mass accumulation of the 17 assessed elements on the binding gel and the corresponding standardized laser ablation signals (signals of elements divided by signals of internal standard 13C), proving the feasibility of LA-ICP-MS analysis. Good analytical precision (RSD<12 %) was achieved for all 17 elements. A hybrid sensor comprising the novel DGT binding gel overlying an O2 planar optrode was then tested in sediments to evaluate the dynamics of O2 and multiple elements. Results showed that the mobility of As, P and W were controlled by precipitation/dissolution processes with Fe/Mn oxides. V, Co, Ni, Zn, Mo, Cd and Sb were released at the sediment surface with the oxidation of iron sulfides.
Collapse
Affiliation(s)
- Mingyi Ren
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Shiming Ding
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; Nanjing EasySensor Environmental Technology Co., Ltd, Nanjing 210018, China.
| | - Zhihui Dai
- State Key Laboratory of Ore Deposit Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China.
| | - Jingfu Wang
- State Key Laboratory of Environmental Geochemistry, Institute of Geochemistry, Chinese Academy of Sciences, Guiyang 550081, China
| | - Cai Li
- School of Resources and Environment, University of Jinan, Jinan 250022, China
| | - Zhilin Zhong
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jingxin Cao
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Liyuan Yang
- School of Resources and Environment, University of Jinan, Jinan 250022, China
| | - Daniel C W Tsang
- Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong China
| | - Shiwei Xu
- Central Laboratory, Jiangsu Academy of Agricultural Science, Nanjing 210008, China
| | - Chenye Yang
- Central Laboratory, Jiangsu Academy of Agricultural Science, Nanjing 210008, China
| | - Yan Wang
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China; Nanjing EasySensor Environmental Technology Co., Ltd, Nanjing 210018, China
| |
Collapse
|
15
|
Feil SB, Pii Y, Valentinuzzi F, Tiziani R, Mimmo T, Cesco S. Copper toxicity affects phosphorus uptake mechanisms at molecular and physiological levels in Cucumis sativus plants. PLANT PHYSIOLOGY AND BIOCHEMISTRY : PPB 2020; 157:138-147. [PMID: 33113485 DOI: 10.1016/j.plaphy.2020.10.023] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 10/16/2020] [Indexed: 05/28/2023]
Abstract
Due to the deliberate use of cupric fungicides in the last century for crop-defence programs, copper (Cu) has considerably accumulated in the soil. The concentrations of Cu often exceed the safety limits of risk assessment for Cu in soil and this may cause toxicity in plants. Copper toxicity induces nutritional imbalances in plants and constraints to plants growth. These aspects might be of paramount importance in the case of phosphorus (P), which is an essential plant macronutrient. In this work, hydroponically grown cucumber plants were used to investigate the influence of the exposure to different Cu concentrations (0.2, 5, 25 and 50 μM) on i) the phenotypic traits of plants, particularly at root level, ii) the nutrient content in both roots and shoots, and iii) the P uptake mechanisms, considering both the biochemical and molecular aspects. At high Cu concentrations (i.e. above 25 μM), the shoot and root growth resulted stunted and the P influx rate diminished. Furthermore, two P transporter genes (i.e. CsPT1.4 and CsPT1.9) were upregulated at the highest Cu concentration, albeit with different induction kinetics. Overall, these results confirm that high Cu concentrations can limit the root acquisition of P, most likely via a direct action on the uptake mechanisms (e.g. transporters). However, the alteration of root plasma membrane permeability induced by Cu toxicity might also play a pivotal role in the observed phenomenon.
Collapse
Affiliation(s)
- Sebastian B Feil
- Faculty of Science and Technology, Free University of Bozen-Bolzano, I-39100, Bolzano, Italy
| | - Youry Pii
- Faculty of Science and Technology, Free University of Bozen-Bolzano, I-39100, Bolzano, Italy.
| | - Fabio Valentinuzzi
- Faculty of Science and Technology, Free University of Bozen-Bolzano, I-39100, Bolzano, Italy
| | - Raphael Tiziani
- Faculty of Science and Technology, Free University of Bozen-Bolzano, I-39100, Bolzano, Italy
| | - Tanja Mimmo
- Faculty of Science and Technology, Free University of Bozen-Bolzano, I-39100, Bolzano, Italy; Competence Centre of Plant Health, Free University of Bozen/Bolzano, I-39100, Bolzano, Italy
| | - Stefano Cesco
- Faculty of Science and Technology, Free University of Bozen-Bolzano, I-39100, Bolzano, Italy
| |
Collapse
|
16
|
Wang X, Whalley WR, Miller AJ, White PJ, Zhang F, Shen J. Sustainable Cropping Requires Adaptation to a Heterogeneous Rhizosphere. TRENDS IN PLANT SCIENCE 2020; 25:1194-1202. [PMID: 32830043 DOI: 10.1016/j.tplants.2020.07.006] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/30/2020] [Revised: 07/02/2020] [Accepted: 07/09/2020] [Indexed: 05/19/2023]
Abstract
Root-soil interactions in the rhizosphere are central to resource acquisition and crop production in agricultural systems. However, apart from studies in idealized experimental systems, rhizosphere processes in real agricultural soils in situ are largely uncharacterized. This limits the contribution of rhizosphere science to agriculture and the ongoing Green Revolution. Here, we argue that understanding plant responses to soil heterogeneity is key to understanding rhizosphere processes. We highlight rhizosphere sensing and root-induced soil modification in the context of heterogeneous soil structure, resource distribution, and root-soil interactions. A deeper understanding of the integrated and dynamic root-soil interactions in the heterogeneously structured rhizosphere could increase crop production and resource use efficiency towards sustainable agriculture.
Collapse
Affiliation(s)
- Xin Wang
- Department of Plant Nutrition, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, China Agricultural University, Key Laboratory of Plant-Soil Interactions, Ministry of Education, Beijing 100193, PR China
| | | | | | - Philip J White
- Ecological Science Group, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK; National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Distinguished Scientist Fellowship Program, King Saud University, Riyadh 11451, Saudi Arabia
| | - Fusuo Zhang
- Department of Plant Nutrition, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, China Agricultural University, Key Laboratory of Plant-Soil Interactions, Ministry of Education, Beijing 100193, PR China
| | - Jianbo Shen
- Department of Plant Nutrition, College of Resources and Environmental Sciences, National Academy of Agriculture Green Development, China Agricultural University, Key Laboratory of Plant-Soil Interactions, Ministry of Education, Beijing 100193, PR China.
| |
Collapse
|
17
|
Steinegger A, Wolfbeis OS, Borisov SM. Optical Sensing and Imaging of pH Values: Spectroscopies, Materials, and Applications. Chem Rev 2020; 120:12357-12489. [PMID: 33147405 PMCID: PMC7705895 DOI: 10.1021/acs.chemrev.0c00451] [Citation(s) in RCA: 182] [Impact Index Per Article: 45.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/15/2020] [Indexed: 12/13/2022]
Abstract
This is the first comprehensive review on methods and materials for use in optical sensing of pH values and on applications of such sensors. The Review starts with an introduction that contains subsections on the definition of the pH value, a brief look back on optical methods for sensing of pH, on the effects of ionic strength on pH values and pKa values, on the selectivity, sensitivity, precision, dynamic ranges, and temperature dependence of such sensors. Commonly used optical sensing schemes are covered in a next main chapter, with subsections on methods based on absorptiometry, reflectometry, luminescence, refractive index, surface plasmon resonance, photonic crystals, turbidity, mechanical displacement, interferometry, and solvatochromism. This is followed by sections on absorptiometric and luminescent molecular probes for use pH in sensors. Further large sections cover polymeric hosts and supports, and methods for immobilization of indicator dyes. Further and more specific sections summarize the state of the art in materials with dual functionality (indicator and host), nanomaterials, sensors based on upconversion and 2-photon absorption, multiparameter sensors, imaging, and sensors for extreme pH values. A chapter on the many sensing formats has subsections on planar, fiber optic, evanescent wave, refractive index, surface plasmon resonance and holography based sensor designs, and on distributed sensing. Another section summarizes selected applications in areas, such as medicine, biology, oceanography, bioprocess monitoring, corrosion studies, on the use of pH sensors as transducers in biosensors and chemical sensors, and their integration into flow-injection analyzers, microfluidic devices, and lab-on-a-chip systems. An extra section is devoted to current challenges, with subsections on challenges of general nature and those of specific nature. A concluding section gives an outlook on potential future trends and perspectives.
Collapse
Affiliation(s)
- Andreas Steinegger
- Institute
of Analytical Chemistry and Food Chemistry, Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria
| | - Otto S. Wolfbeis
- Institute
of Analytical Chemistry, Chemo- and Biosensors, University of Regensburg, D-93040 Regensburg, Germany
| | - Sergey M. Borisov
- Institute
of Analytical Chemistry and Food Chemistry, Graz University of Technology, Stremayrgasse 9, A-8010 Graz, Austria
| |
Collapse
|
18
|
Touhami D, McDowell RW, Condron LM. Role of Organic Anions and Phosphatase Enzymes in Phosphorus Acquisition in the Rhizospheres of Legumes and Grasses Grown in a Low Phosphorus Pasture Soil. PLANTS (BASEL, SWITZERLAND) 2020; 9:E1185. [PMID: 32932934 PMCID: PMC7570192 DOI: 10.3390/plants9091185] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 08/14/2020] [Revised: 09/08/2020] [Accepted: 09/09/2020] [Indexed: 11/16/2022]
Abstract
Rhizosphere processes play a critical role in phosphorus (P) acquisition by plants and microbes, especially under P-limited conditions. Here, we investigated the impacts of nutrient addition and plant species on plant growth, rhizosphere processes, and soil P dynamics. In a glasshouse experiment, blue lupin (Lupinus angustifolius), white clover (Trifolium repens L.), perennial ryegrass (Lolium perenne L.), and wheat (Triticum aestivum L.) were grown in a low-P pasture soil for 8 weeks with and without the single and combined addition of P (33 mg kg-1) and nitrogen (200 mg kg-1). Phosphorus addition increased plant biomass and total P content across plant species, as well as microbial biomass P in white clover and ryegrass. Alkaline phosphatase activity was higher for blue lupin. Legumes showed higher concentrations of organic anions compared to grasses. After P addition, the concentrations of organic anions increased by 11-,10-, 5-, and 2-fold in the rhizospheres of blue lupin, white clover, wheat, and ryegrass, respectively. Despite the differences in their chemical availability (as assessed by P fractionation), moderately labile inorganic P and stable organic P were the most depleted fractions by the four plant species. Inorganic P fractions were depleted similarly between the four plant species, while blue lupin exhibited a strong depletion of stable organic P. Our findings suggest that organic anions were not related to the acquisition of inorganic P for legumes and grasses. At the same time, alkaline phosphatase activity was associated with the mobilization of stable organic P for blue lupin.
Collapse
Affiliation(s)
- Driss Touhami
- Faculty of Agriculture and Life Sciences, P.O. Box 85084, Lincoln University, Lincoln 7647, Christchurch, New Zealand; (R.W.M.); (L.M.C.)
- AgroBioSciences Program, Mohammed VI Polytechnic University (UM6P), Hay Moulay Rachid, Ben Guerir 43150, Morocco
| | - Richard W. McDowell
- Faculty of Agriculture and Life Sciences, P.O. Box 85084, Lincoln University, Lincoln 7647, Christchurch, New Zealand; (R.W.M.); (L.M.C.)
- AgResearch Limited, Lincoln Research Centre, Private Bag 4749, Christchurch, New Zealand
| | - Leo M. Condron
- Faculty of Agriculture and Life Sciences, P.O. Box 85084, Lincoln University, Lincoln 7647, Christchurch, New Zealand; (R.W.M.); (L.M.C.)
| |
Collapse
|
19
|
Wagner S, Hoefer C, Puschenreiter M, Wenzel WW, Oburger E, Hann S, Robinson B, Kretzschmar R, Santner J. Arsenic redox transformations and cycling in the rhizosphere of Pteris vittata and Pteris quadriaurita. ENVIRONMENTAL AND EXPERIMENTAL BOTANY 2020; 177:104122. [PMID: 34103771 PMCID: PMC7610922 DOI: 10.1016/j.envexpbot.2020.104122] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/19/2023]
Abstract
Pteris vittata (PV) and Pteris quadriaurita (PQ) are reported to hyperaccumulate arsenic (As) when grown in Asrich soil. Yet, little is known about the impact of their unique As accumulation mechanisms on As transformations and cycling at the soil-root interface. Using a combined approach of two-dimensional (2D), sub-mm scale solute imaging of arsenite (AsIII), arsenate (AsV), phosphorus (P), manganese (Mn), iron (Fe) and oxygen (O2), we found localized patterns of AsIII/AsV redox transformations in the PV rhizosphere (AsIII/AsV ratio of 0.57) compared to bulk soil (AsIII/AsV ratio of ≤0.04). Our data indicate that the high As root uptake, translocation and accumulation from the As-rich experimental soil (2080 mg kg-1) to PV fronds (6986 mg kg-1) induced As detoxification via AsV reduction and AsIII root efflux, leading to AsIII accumulation and re-oxidation to AsV in the rhizosphere porewater. This As cycling mechanism is linked to the reduction of O2 and MnIII/IV (oxyhydr)oxides resulting in decreased O2 levels and increased Mn solubilization along roots. Compared to PV, we found 4-fold lower As translocation to PQ fronds (1611 mg kg-1), 2-fold lower AsV depletion in the PQ rhizosphere, and no AsIII efflux from PQ roots, suggesting that PQ efficiently controls As uptake to avoid toxic As levels in roots. Analysis of root exudates obtained from soil-grown PV showed that As acquisition by PV roots was not associated with phytic acid release. Our study demonstrates that two closely-related As-accumulating ferns have distinct mechanisms for As uptake modulating As cycling in As-rich environments.
Collapse
Affiliation(s)
- Stefan Wagner
- Department of Forest and Soil Sciences, Institute of Soil Research, Rhizosphere Ecology & Biogeochemistry Group, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430, Tulln, Austria
- Department General, Analytical and Physical Chemistry, Chair of General and Analytical Chemistry, Montanuniversität Leoben, Franz-Josef-Strasse 18, 8700, Leoben, Austria
- Department of Chemistry, Institute of Analytical Chemistry, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190, Vienna, Austria
| | - Christoph Hoefer
- Department of Forest and Soil Sciences, Institute of Soil Research, Rhizosphere Ecology & Biogeochemistry Group, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430, Tulln, Austria
- Department of Environmental Systems Science, Institute of Biogeochemistry and Pollutant Dynamics, Soil Chemistry Group, ETH Zürich, Universitätstrasse 16, CHN, 8092, Zürich, Switzerland
| | - Markus Puschenreiter
- Department of Forest and Soil Sciences, Institute of Soil Research, Rhizosphere Ecology & Biogeochemistry Group, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430, Tulln, Austria
| | - Walter W. Wenzel
- Department of Forest and Soil Sciences, Institute of Soil Research, Rhizosphere Ecology & Biogeochemistry Group, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430, Tulln, Austria
| | - Eva Oburger
- Department of Forest and Soil Sciences, Institute of Soil Research, Rhizosphere Ecology & Biogeochemistry Group, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430, Tulln, Austria
| | - Stephan Hann
- Department of Chemistry, Institute of Analytical Chemistry, University of Natural Resources and Life Sciences, Vienna, Muthgasse 18, 1190, Vienna, Austria
| | - Brett Robinson
- School of Physical and Chemical Sciences, University of Canterbury, 20 Kirkwood Ave, Ilam, Christchurch, 8041, New Zealand
| | - Ruben Kretzschmar
- Department of Environmental Systems Science, Institute of Biogeochemistry and Pollutant Dynamics, Soil Chemistry Group, ETH Zürich, Universitätstrasse 16, CHN, 8092, Zürich, Switzerland
| | - Jakob Santner
- Department General, Analytical and Physical Chemistry, Chair of General and Analytical Chemistry, Montanuniversität Leoben, Franz-Josef-Strasse 18, 8700, Leoben, Austria
- Department of Crop Sciences, Institute of Agronomy, University of Natural Resources and Life Sciences, Vienna, Konrad-Lorenz-Strasse 24, 3430, Tulln, Austria
- Corresponding author. (J. Santner)
| |
Collapse
|
20
|
Siao W, Coskun D, Baluška F, Kronzucker HJ, Xu W. Root-Apex Proton Fluxes at the Centre of Soil-Stress Acclimation. TRENDS IN PLANT SCIENCE 2020; 25:794-804. [PMID: 32673580 DOI: 10.1016/j.tplants.2020.03.002] [Citation(s) in RCA: 25] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/30/2019] [Revised: 02/13/2020] [Accepted: 03/04/2020] [Indexed: 05/22/2023]
Abstract
Proton (H+) fluxes in plant roots play critical roles in maintaining root growth and facilitating plant responses to multiple soil stresses, including fluctuations in nutrient supply, salt infiltration, and water stress. Soil mining for nutrients and water, rates of nutrient uptake, and the modulation of cell expansion all depend on the regulation of root H+ fluxes, particularly at the root apex, mediated primarily by the activity of plasma membrane (PM) H+-ATPases. Here, we summarize recent findings on the regulatory mechanisms of H+ fluxes at the root apex under three abiotic stress conditions - phosphate deficiency, salinity stress, and water deficiency - and present an integrated physiomolecular view of the functions of H+ fluxes in maintaining root growth in the acclimation to soil stress.
Collapse
Affiliation(s)
- Wei Siao
- Center for Plant Water-Use and Nutrition Regulation and College of Life Sciences, Joint International Research Laboratory of Water and Nutrient in Crop, Fujian Agriculture and Forestry University, Jinshan Fuzhou 350002, China; Department of Plant Biotechnology and Bioinformatics, Ghent University, 9052 Ghent, Belgium; Center for Plant Systems Biology, VIB, 9052 Ghent, Belgium
| | - Devrim Coskun
- Département de Phytologie, Faculté des Sciences de l'Agriculture et de l'Alimentation, Université Laval, Québec, QC G1V 0A6, Canada
| | - František Baluška
- Institute of Cellular and Molecular Botany, University of Bonn, 53115 Bonn, Germany
| | - Herbert J Kronzucker
- School of Agriculture and Food, Faculty of Veterinary and Agricultural Sciences, The University of Melbourne, VIC 3010, Australia; Faculty of Land and Food Systems, University of British Columbia, Vancouver, BC V6T 1Z4, Canada.
| | - Weifeng Xu
- Center for Plant Water-Use and Nutrition Regulation and College of Life Sciences, Joint International Research Laboratory of Water and Nutrient in Crop, Fujian Agriculture and Forestry University, Jinshan Fuzhou 350002, China.
| |
Collapse
|
21
|
Fang W, Shi X, Yang D, Hu X, Williams PN, Shi B, Liu Z, Luo J. In Situ Selective Measurement Based on Diffusive Gradients in Thin Films Technique with Mercapto-Functionalized Mesoporous Silica for High-Resolution Imaging of Sb III in Soil. Anal Chem 2020; 92:3581-3588. [PMID: 31916433 DOI: 10.1021/acs.analchem.9b04225] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In situ monitoring of Sb speciation improves the understanding of Sb biogeochemistry and toxicity in ecosystems. Precise measurement of Sb is a challenge due to its instability of oxidation and ultratrace concentration. The development of simple and reliable methods specific to SbIII measurement is not only appealing but essential for implementing regulations. Here, we present an in situ speciation analysis method for SbIII, using the diffusive gradients in thin films (DGT) technique, combined with mercapto-functionalized SBA-15 mesoporous silica nanoparticles (MSBA). Laboratory performance tests confirmed MSBA-DGT uptake was independent of pH (4-9) and ionic strength (0.1-200 mmol L-1). DGT devices equipped with MSBA-based binding gels showed a theoretically linear accumulation of SbIII and exhibited a high capacity for SbIII at 65 μg/gel disc, with negligible accumulation of SbV over a 72 h deployment. Compared with commercial 3-mercaptopropyl-functionalized silica (MFS), the nanosized MSBA facilitate its even distribution in the binding gels. Furthermore, the good selectivity and high homogeneity of the MSBA gel enabled it to be applied in a rice rhizosphere in conjunction with AgI gel to investigate the effects of sulfur application on the SbIII solubility. In summary, the newly developed MSBA-DGT provides a selective measurement of SbIII, showing potential for environmental monitoring and further application in understanding the biogeochemical process of Sb.
Collapse
Affiliation(s)
- Wen Fang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China
| | - Xinyao Shi
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China
| | - Danxing Yang
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China
| | - Xuan Hu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China
| | - Paul N Williams
- Institute for Global Food Security, School of Biological Sciences, Queen's University Belfast, Belfast BT9 7BL, United Kingdom
| | - Bingqing Shi
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China
| | - Zhaodong Liu
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China
| | - Jun Luo
- State Key Laboratory of Pollution Control and Resource Reuse, School of the Environment, Nanjing University, Jiangsu 210023, China
| |
Collapse
|
22
|
Wang Y, Yuan JH, Chen H, Zhao X, Wang D, Wang SQ, Ding SM. Small-scale interaction of iron and phosphorus in flooded soils with rice growth. THE SCIENCE OF THE TOTAL ENVIRONMENT 2019; 669:911-919. [PMID: 30970458 DOI: 10.1016/j.scitotenv.2019.03.054] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/30/2018] [Revised: 03/04/2019] [Accepted: 03/04/2019] [Indexed: 06/09/2023]
Abstract
In the rhizosphere of flooded paddy soils, the solubilization, efflux, and uptake of phosphorus (P) are highly intertwined with iron (Fe) redox cycling. However, the direct observation of Fe-P coupling in the rhizosphere is challenging. This study combined high-resolution dialysis (HR-Peeper) and diffusive gradients in thin films (DGT) techniques to capture the one-dimensional distributions of soluble reactive P (SRP), soluble Fe(II), and labile P and Fe in the root zone of rice (Oryza sativa L.), respectively. The results show a depletion of soluble/labile P and Fe concentrations around the rice root zone, compared to anaerobic bulk soils that have two different soil Olsen-P levels. Two-dimensional (2D) measurements of DGT-labile P concentrations exhibited similar but stronger trends of P depletion due to uptake of P from soil solids. In low-P soil treatment, 97.8% soluble Fe(II) was depleted in the rice root zone relative to bulk soil, and a 540% enrichment of total Fe in Fe plaques appeared in comparison to that in high-P soil. This demonstrated that the rice plant showed an adaptive metabolic reaction to combat P deficiency in low-P soil by increasing Fe plaque formation. This reaction directly resulted in stronger depletion of P in low-P soil, as indicated by the results of 2D measurements of DGT-labile P concentrations. Moreover, the significant (P < 0.001, R2 = 0.175-0.951) positive corrections between SRP vs. soluble Fe(II), and DGT-labile P vs. Fe were observed in combination with pronounced peaks at the same position in the rice root zone, thus verifying that the cycling of Fe dictated P depletion. A notably lower value of the DGT-labile Fe/P ratio was found in high-P soil, which indicates a relatively higher risk of P release compared to that in low-P soil.
Collapse
Affiliation(s)
- Yu Wang
- State Key Laboratory of Soil and Sustainable Agriculture, Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Jia-Hui Yuan
- State Key Laboratory of Soil and Sustainable Agriculture, Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Hao Chen
- State Key Laboratory of Soil and Sustainable Agriculture, Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Xu Zhao
- State Key Laboratory of Soil and Sustainable Agriculture, Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China
| | - Dengjun Wang
- National Research Council Resident Research Associate, United States Environmental Protection Agency, Ada, 74820, USA
| | - Shen-Qiang Wang
- State Key Laboratory of Soil and Sustainable Agriculture, Changshu National Agro-Ecosystem Observation and Research Station, Institute of Soil Science, Institute of Soil Science, Chinese Academy of Sciences, Nanjing 210008, China.
| | - Shi-Ming Ding
- State Key Laboratory of Lake Science and Environment, Nanjing Institute of Geography and Limnology, Chinese Academy of Sciences, Nanjing 210008, China.
| |
Collapse
|
23
|
Sugiyama A. The soybean rhizosphere: Metabolites, microbes, and beyond-A review. J Adv Res 2019; 19:67-73. [PMID: 31341671 PMCID: PMC6630087 DOI: 10.1016/j.jare.2019.03.005] [Citation(s) in RCA: 69] [Impact Index Per Article: 13.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/2018] [Revised: 03/15/2019] [Accepted: 03/16/2019] [Indexed: 11/17/2022] Open
Abstract
Rhizosphere microbial communities are important for plant health. Specialized metabolites in the rhizosphere influence the microbial communities. Isoflavones and saponins are major specialized metabolites secreted by soybean. Secretion is regulated developmentally and nutritionally. Possible links between specialized metabolites and microbial communities are highlighted.
The rhizosphere is the region close to a plant’s roots, where various interactions occur. Recent evidence indicates that plants influence rhizosphere microbial communities by secreting various metabolites and, in turn, the microbes influence the growth and health of the plants. Despite the importance of plant-derived metabolites in the rhizosphere, relatively little is known about their spatiotemporal distribution and dynamics. In addition to being an important crop, soybean (Glycine max) is a good model plant with which to study these rhizosphere interactions, because soybean plants have symbiotic relationships with rhizobia and arbuscular mycorrhizal fungi and secrete various specialized metabolites, such as isoflavones and saponins, into the soil. This review summarizes the characteristics of the soybean rhizosphere from the viewpoint of specialized metabolites and microbes and discusses future research perspectives. In sum, secretion of these metabolites is developmentally and nutritionally regulated and potentially alters the rhizosphere microbial communities.
Collapse
Affiliation(s)
- Akifumi Sugiyama
- Research Institute for Sustainable Humanosphere, Kyoto University, Uji 611-0011, Japan
| |
Collapse
|