1
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Geilfus CM, Zörb C, Jones JJ, Wimmer MA, Schmöckel SM. Water for agriculture: more crop per drop. PLANT BIOLOGY (STUTTGART, GERMANY) 2024; 26:499-507. [PMID: 38773740 DOI: 10.1111/plb.13652] [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: 06/30/2023] [Accepted: 04/04/2024] [Indexed: 05/24/2024]
Abstract
Global crop production in agriculture depends on water availability. Future scenarios predict increasing occurrence of flash floods and rapidly developing droughts accompanied by heatwaves in humid regions that rely on rain-fed agriculture. It is challenging to maintain high crop yields, even in arid and drought-prone regions that depend on irrigation. The average water demand of crops varies significantly, depending on plant species, development stage, and climate. Most crops, such as maize and wheat, require relatively more water during the vegetative phase compared to the ripening phase. In this review, we explain WUE and options to improve water use and thus crop yield. Nutrient management might represent another possibility to manipulate water uptake and use by plants. An emerging topic involves agroforest co-cultivation, where trees in the system facilitate water transfer through hydraulic lift, benefiting neighbouring crops. Other options to enhance crop yield per water use are discussed.
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Affiliation(s)
- C-M Geilfus
- Department of Plant Nutrition and Soil Science, Hochschule Geisenheim University, Geisenheim, Germany
| | - C Zörb
- Department Quality of Plant Products, Institute of Crop Science, University of Hohenheim, Stuttgart, Germany
| | - J J Jones
- Division of Controlled Environment Horticulture, Faculty of Life Sciences, Albrecht Daniel Thaer-Institute of Agricultural and Horticultural Sciences, Humboldt-University of Berlin, Berlin, Germany
| | - M A Wimmer
- Department Quality of Plant Products, Institute of Crop Science, University of Hohenheim, Stuttgart, Germany
| | - S M Schmöckel
- Department Physiology of Yield Stability, Institute of Crop Science, University of Hohenheim, Stuttgart, Germany
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2
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Ragland CJ, Shih KY, Dinneny JR. Choreographing root architecture and rhizosphere interactions through synthetic biology. Nat Commun 2024; 15:1370. [PMID: 38355570 PMCID: PMC10866969 DOI: 10.1038/s41467-024-45272-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/17/2023] [Accepted: 01/18/2024] [Indexed: 02/16/2024] Open
Abstract
Climate change is driving extreme changes to the environment, posing substantial threats to global food security and bioenergy. Given the direct role of plant roots in mediating plant-environment interactions, engineering the form and function of root systems and their associated microbiota may mitigate these effects. Synthetic genetic circuits have enabled sophisticated control of gene expression in microbial systems for years and a surge of advances has heralded the extension of this approach to multicellular plant species. Targeting these tools to affect root structure, exudation, and microbe activity on root surfaces provide multiple strategies for the advancement of climate-ready crops.
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Affiliation(s)
- Carin J Ragland
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - Kevin Y Shih
- Department of Biology, Stanford University, Stanford, CA, 94305, USA
| | - José R Dinneny
- Department of Biology, Stanford University, Stanford, CA, 94305, USA.
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3
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Afridi MS, Kumar A, Javed MA, Dubey A, de Medeiros FHV, Santoyo G. Harnessing root exudates for plant microbiome engineering and stress resistance in plants. Microbiol Res 2024; 279:127564. [PMID: 38071833 DOI: 10.1016/j.micres.2023.127564] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 11/02/2023] [Accepted: 11/27/2023] [Indexed: 12/23/2023]
Abstract
A wide range of abiotic and biotic stresses adversely affect plant's growth and production. Under stress, one of the main responses of plants is the modulation of exudates excreted in the rhizosphere, which consequently leads to alterations in the resident microbiota. Thus, the exudates discharged into the rhizospheric environment play a preponderant role in the association and formation of plant-microbe interactions. In this review, we aimed to provide a synthesis of the latest and most pertinent literature on the diverse biochemical and structural compositions of plant root exudates. Also, this work investigates into their multifaceted role in microbial nutrition and intricate signaling processes within the rhizosphere, which includes quorum-sensing molecules. Specifically, it explores the contributions of low molecular weight compounds, such as carbohydrates, phenolics, organic acids, amino acids, and secondary metabolites, as well as the significance of high molecular weight compounds, including proteins and polysaccharides. It also discusses the state-of-the-art omics strategies that unveil the vital role of root exudates in plant-microbiome interactions, including defense against pathogens like nematodes and fungi. We propose multiple challenges and perspectives, including exploiting plant root exudates for host-mediated microbiome engineering. In this discourse, root exudates and their derived interactions with the rhizospheric microbiota should receive greater attention due to their positive influence on plant health and stress mitigation.
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Affiliation(s)
- Muhammad Siddique Afridi
- Department of Plant Pathology, Federal University of Lavras, CP3037, 37200-900 Lavras, MG, Brazil.
| | - Ashwani Kumar
- Metagenomics and Secretomics Research Laboratory, Department of Botany, Dr. Harisingh Gour University (A Central University), Sagar 470003, MP, India
| | - Muhammad Ammar Javed
- Institute of Industrial Biotechnology, Government College University, Lahore 54000, Pakistan
| | - Anamika Dubey
- Metagenomics and Secretomics Research Laboratory, Department of Botany, Dr. Harisingh Gour University (A Central University), Sagar 470003, MP, India
| | | | - Gustavo Santoyo
- Instituto de Investigaciones Químico Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, 58030 Morelia, Mexico.
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4
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Xiao T, Li P, Fei W, Wang J. Effects of vegetation roots on the structure and hydraulic properties of soils: A perspective review. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 906:167524. [PMID: 37793452 DOI: 10.1016/j.scitotenv.2023.167524] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/15/2023] [Revised: 09/22/2023] [Accepted: 09/29/2023] [Indexed: 10/06/2023]
Abstract
This paper aims to provide a state-of-the-art review on the effects of vegetation roots on the soil structure and soil hydraulic properties. After a thorough review of current studies, the effects of vegetation roots are summarized into four: root exudation, root penetration, root water uptake and root decay. Root exudates alter the size and stability of aggregates, the contact angle of soil, and the viscosity and surface tension of pore fluid; root exudates of crops always increase the soil water retention capacity and decrease the soil saturated hydraulic conductivity. Root penetration creates new pores or clogs existing pores during root growth, and root parameters (e.g., root biomass density, root diameter and root length density) are well correlated to soil hydraulic properties. Root water uptake can apparently increase the soil water retention capacity by providing an additional negative pressure and induce micro-fissures and macropores in the rhizosphere soil. Root decay modifies the pore structure and water repellency of soil, resulting in the increase of soil macro-porosity, soil water retention, and the saturated hydraulic conductivity or steady infiltration rate. Some of the above four effects may be difficult to be distinguished, and most importantly each is highly time-dependent and influenced by a multitude of plant-related and soil-related factors. Therefore, it remains a significant challenge to comprehend and quantify the effects of vegetation roots on the soil structure and soil hydraulic properties. Unsolved questions and disputes that require further investigations in the future are summarized in this review.
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Affiliation(s)
- Tao Xiao
- State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an 710069, China.
| | - Ping Li
- State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an 710069, China; Water Cycle and Geological Environment Observation and Research Station for the Chinese Loess Plateau, Ministry of Education, Zhengning 745339, China.
| | - Wenbin Fei
- Department of Infrastructure Engineering, The University of Melbourne, Parkville, Australia.
| | - Jiading Wang
- State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi'an 710069, China.
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5
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Koehler T, Wankmüller FJP, Sadok W, Carminati A. Transpiration response to soil drying versus increasing vapor pressure deficit in crops: physical and physiological mechanisms and key plant traits. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:4789-4807. [PMID: 37354081 PMCID: PMC10474596 DOI: 10.1093/jxb/erad221] [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: 02/09/2023] [Accepted: 06/07/2023] [Indexed: 06/26/2023]
Abstract
The water deficit experienced by crops is a function of atmospheric water demand (vapor pressure deficit) and soil water supply over the whole crop cycle. We summarize typical transpiration response patterns to soil and atmospheric drying and the sensitivity to plant hydraulic traits. We explain the transpiration response patterns using a soil-plant hydraulic framework. In both cases of drying, stomatal closure is triggered by limitations in soil-plant hydraulic conductance. However, traits impacting the transpiration response differ between the two drying processes and act at different time scales. A low plant hydraulic conductance triggers an earlier restriction in transpiration during increasing vapor pressure deficit. During soil drying, the impact of the plant hydraulic conductance is less obvious. It is rather a decrease in the belowground hydraulic conductance (related to soil hydraulic properties and root length density) that is involved in transpiration down-regulation. The transpiration response to increasing vapor pressure deficit has a daily time scale. In the case of soil drying, it acts on a seasonal scale. Varieties that are conservative in water use on a daily scale may not be conservative over longer time scales (e.g. during soil drying). This potential independence of strategies needs to be considered in environment-specific breeding for yield-based drought tolerance.
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Affiliation(s)
- Tina Koehler
- Physics of Soils and Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
- Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Fabian J P Wankmüller
- Physics of Soils and Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
| | - Walid Sadok
- Agronomy and Plant Genetics, College of Food, Agricultural and Natural Resource Sciences, University of Minnesota, Twin Cities, MN, USA
| | - Andrea Carminati
- Physics of Soils and Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
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6
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Lin HA, Coker HR, Howe JA, Tfaily MM, Nagy EM, Antony-Babu S, Hague S, Smith AP. Progressive drought alters the root exudate metabolome and differentially activates metabolic pathways in cotton ( Gossypium hirsutum). FRONTIERS IN PLANT SCIENCE 2023; 14:1244591. [PMID: 37711297 PMCID: PMC10499043 DOI: 10.3389/fpls.2023.1244591] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/22/2023] [Accepted: 08/14/2023] [Indexed: 09/16/2023]
Abstract
Root exudates comprise various primary and secondary metabolites that are responsive to plant stressors, including drought. As increasing drought episodes are predicted with climate change, identifying shifts in the metabolome profile of drought-induced root exudation is necessary to understand the molecular interactions that govern the relationships between plants, microbiomes, and the environment, which will ultimately aid in developing strategies for sustainable agriculture management. This study utilized an aeroponic system to simulate progressive drought and recovery while non-destructively collecting cotton (Gossypium hirsutum) root exudates. The molecular composition of the collected root exudates was characterized by untargeted metabolomics using Fourier-Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) and mapped to the Kyoto Encyclopedia of Genes and Genomes (KEGG) databases. Over 700 unique drought-induced metabolites were identified throughout the water-deficit phase. Potential KEGG pathways and KEGG modules associated with the biosynthesis of flavonoid compounds, plant hormones (abscisic acid and jasmonic acid), and other secondary metabolites were highly induced under severe drought, but not at the wilting point. Additionally, the associated precursors of these metabolites, such as amino acids (phenylalanine and tyrosine), phenylpropanoids, and carotenoids, were also mapped. The potential biochemical transformations were further calculated using the data generated by FT-ICR MS. Under severe drought stress, the highest number of potential biochemical transformations, including methylation, ethyl addition, and oxidation/hydroxylation, were identified, many of which are known reactions in some of the mapped pathways. With the application of FT-ICR MS, we revealed the dynamics of drought-induced secondary metabolites in root exudates in response to drought, providing valuable information for drought-tolerance strategies in cotton.
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Affiliation(s)
- Heng-An Lin
- Department of Soil and Crop Sciences, Texas A&M University and Texas A&M AgriLife Research, College Station, TX, United States
| | - Harrison R. Coker
- Department of Soil and Crop Sciences, Texas A&M University and Texas A&M AgriLife Research, College Station, TX, United States
| | - Julie A. Howe
- Department of Soil and Crop Sciences, Texas A&M University and Texas A&M AgriLife Research, College Station, TX, United States
| | - Malak M. Tfaily
- Department of Environmental Science, University of Arizona, Tucson, AZ, United States
| | - Elek M. Nagy
- Department of Plant Pathology and Microbiology, Texas A&M University and Texas A&M AgriLife Research, College Station, TX, United States
| | - Sanjay Antony-Babu
- Department of Plant Pathology and Microbiology, Texas A&M University and Texas A&M AgriLife Research, College Station, TX, United States
| | - Steve Hague
- Department of Soil and Crop Sciences, Texas A&M University and Texas A&M AgriLife Research, College Station, TX, United States
| | - A. Peyton Smith
- Department of Soil and Crop Sciences, Texas A&M University and Texas A&M AgriLife Research, College Station, TX, United States
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7
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Berauer BJ, Akale A, Schweiger AH, Knott M, Diehl D, Wolf M, Sawers RJH, Ahmed MA. Differences in mucilage properties and stomatal sensitivity of locally adapted Zea mays in relation with precipitation seasonality and vapour pressure deficit regime of their native environment. PLANT DIRECT 2023; 7:e519. [PMID: 37600238 PMCID: PMC10435965 DOI: 10.1002/pld3.519] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/17/2023] [Revised: 07/05/2023] [Accepted: 07/27/2023] [Indexed: 08/22/2023]
Abstract
With ongoing climate change and the increase in extreme weather events, especially droughts, the challenge of maintaining food security is becoming ever greater. Locally adapted landraces of crops represent a valuable source of adaptation to stressful environments. In the light of future droughts-both by altered soil water supply and increasing atmospheric water demand (vapor pressure deficit [VPD])-plants need to improve their water efficiency. To do so, plants can enhance their access to soil water by improving rhizosphere hydraulic conductivity via the exudation of mucilage. Furthermore, plants can reduce transpirational water loss via stomatal regulation. Although the role of mucilage and stomata regulation on plant water management have been extensively studied, little is known about a possible coordination between root mucilage properties and stomatal sensitivity as well as abiotic drivers shaping the development of drought resistant trait suits within landraces. Mucilage properties and stomatal sensitivity of eight Mexican landraces of Zea mays in contrast with one inbred line were first quantified under controlled conditions and second related to water demand and supply at their respective site of origin. Mucilage physical properties-namely, viscosity, contact angle, and surface tension-differed between the investigated maize varieties. We found strong influences of precipitation seasonality, thus plant water availability, on mucilage production (R 2 = .88, p < .01) and mucilage viscosity (R 2 = .93, p < .01). Further, stomatal sensitivity to increased atmospheric water demand was related to mucilage viscosity and contact angle, both of which are crucial in determining mucilage's water repellent, thus maladaptive, behavior upon soil drying. The identification of landraces with pre-adapted suitable trait sets with regard to drought resistance is of utmost importance, for example, trait combinations such as exhibited in one of the here investigated landraces. Our results suggest a strong environmental selective force of seasonality in plant water availability on mucilage properties as well as regulatory stomatal effects to avoid mucilage's maladaptive potential upon drying and likely delay critical levels of hydraulic dysfunction. By this, landraces from highly seasonal climates may exhibit beneficial mucilage and stomatal traits to prolong plant functioning under edaphic drought. These findings may help breeders to efficiently screen for local landraces with pre-adaptations to drought to ultimately increase crop yield resistance under future climatic variability.
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Affiliation(s)
- Bernd J. Berauer
- Institute of Landscape and Plant Ecology, Department of Plant EcologyUniversity of HohenheimStuttgartGermany
| | - Asegidew Akale
- Root‐Soil Interaction, TUM School of Life SciencesTechnical University of MunichFreisingGermany
| | - Andreas H. Schweiger
- Institute of Landscape and Plant Ecology, Department of Plant EcologyUniversity of HohenheimStuttgartGermany
| | - Mathilde Knott
- Institute for Environmental Sciences, Group of Environmental and Soil ChemistryRPTU in LandauLandauGermany
| | - Dörte Diehl
- Institute for Environmental Sciences, Group of Environmental and Soil ChemistryRPTU in LandauLandauGermany
| | - Marc‐Philip Wolf
- Institute for Environmental Sciences, Group of Environmental and Soil ChemistryRPTU in LandauLandauGermany
| | - Ruairidh J. H. Sawers
- Department of Plant ScienceThe Pennsylvania State UniversityState CollegePennsylvaniaUSA
| | - Mutez A. Ahmed
- Root‐Soil Interaction, TUM School of Life SciencesTechnical University of MunichFreisingGermany
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8
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Jiang Z, Fu Y, Zhou L, He Y, Zhou G, Dietrich P, Long J, Wang X, Jia S, Ji Y, Jia Z, Song B, Liu R, Zhou X. Plant growth strategy determines the magnitude and direction of drought-induced changes in root exudates in subtropical forests. GLOBAL CHANGE BIOLOGY 2023; 29:3476-3488. [PMID: 36931867 DOI: 10.1111/gcb.16685] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/17/2022] [Revised: 02/27/2023] [Accepted: 03/08/2023] [Indexed: 05/16/2023]
Abstract
Root exudates are an important pathway for plant-microbial interactions and are highly sensitive to climate change. However, how extreme drought affects root exudates and the main components, as well as species-specific differences in response magnitude and direction, are poorly understood. In this study, root exudation rates of total carbon (C) and its components (e.g., sugar, organic acid, and amino acid) were measured under the control and extreme drought treatments (i.e., 70% throughfall reduction) by in situ collection of four tree species with different growth rates in a subtropical forest. We also quantified soil properties, root morphological traits, and mycorrhizal infection rates to examine the driving factors underlying variations in root exudation. Our results showed that extreme drought significantly decreased root exudation rates of total C, sugar, and amino acid by 17.8%, 30.8%, and 35.0%, respectively, but increased root exudation rate of organic acid by 38.6%, which were largely associated with drought-induced changes in tree growth rates, root morphological traits, and mycorrhizal infection rates. Specifically, trees with relatively high growth rates were more responsive to drought for root exudation rates compared with those with relatively low growth rates, which were closely related to root morphological traits and mycorrhizal infection rates. These findings highlight the importance of plant growth strategy in mediating drought-induced changes in root exudation rates. The coordinations among root exudation rates, root morphological traits, and mycorrhizal symbioses in response to drought could be incorporated into land surface models to improve the prediction of climate change impacts on rhizosphere C dynamics in forest ecosystems.
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Affiliation(s)
- Zheng Jiang
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Yuling Fu
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Lingyan Zhou
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Yanghui He
- Northeast Asia Ecosystem Carbon Sink Research Center (NACC), Center for Ecological Research, Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, China
| | - Guiyao Zhou
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Peter Dietrich
- German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, Leipzig, Germany
| | - Jilan Long
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Xinxin Wang
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Shuxian Jia
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Yuhuang Ji
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Zhen Jia
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Bingqian Song
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
| | - Ruiqiang Liu
- Northeast Asia Ecosystem Carbon Sink Research Center (NACC), Center for Ecological Research, Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, China
| | - Xuhui Zhou
- Center for Global Change and Ecological Forecasting, Tiantong National Field Station for Forest Ecosystem, School of Ecological and Environmental Sciences, East China Normal University, Shanghai, China
- Northeast Asia Ecosystem Carbon Sink Research Center (NACC), Center for Ecological Research, Key Laboratory of Sustainable Forest Ecosystem Management-Ministry of Education, School of Forestry, Northeast Forestry University, Harbin, China
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9
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Fadiji AE, Yadav AN, Santoyo G, Babalola OO. Understanding the plant-microbe interactions in environments exposed to abiotic stresses: An overview. Microbiol Res 2023; 271:127368. [PMID: 36965460 DOI: 10.1016/j.micres.2023.127368] [Citation(s) in RCA: 6] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/21/2022] [Revised: 02/07/2023] [Accepted: 03/19/2023] [Indexed: 03/27/2023]
Abstract
Abiotic stress poses a severe danger to agriculture since it negatively impacts cellular homeostasis and eventually stunts plant growth and development. Abiotic stressors like drought and excessive heat are expected to occur more frequently in the future due to climate change, which would reduce the yields of important crops like maize, wheat, and rice which may jeopardize the food security of human populations. The plant microbiomes are a varied and taxonomically organized microbial community that is connected to plants. By supplying nutrients and water to plants, and regulating their physiology and metabolism, plant microbiota frequently helps plants develop and tolerate abiotic stresses, which can boost crop yield under abiotic stresses. In this present study, with emphasis on temperature, salt, and drought stress, we describe current findings on how abiotic stresses impact the plants, microbiomes, microbe-microbe interactions, and plant-microbe interactions as the way microorganisms affect the metabolism and physiology of the plant. We also explore crucial measures that must be taken in applying plant microbiomes in agriculture practices faced with abiotic stresses.
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Affiliation(s)
- Ayomide Emmanuel Fadiji
- Food Security and Safety Focus Area, Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa
| | - Ajar Nath Yadav
- Microbial Biotechnology Laboratory, Department of Biotechnology, Dr. Khem Singh Gill Akal College of Agriculture, Eternal University, Baru Sahib, India
| | - Gustavo Santoyo
- Instituto de Investigaciones Químico-Biológicas, Universidad Michoacana de San Nicolás de Hidalgo, Morelia, Mich 58030, Mexico
| | - Olubukola Oluranti Babalola
- Food Security and Safety Focus Area, Faculty of Natural and Agricultural Sciences, North-West University, Private Bag X2046, Mmabatho 2735, South Africa.
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10
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Abdalla M, Schweiger AH, Berauer BJ, McAdam SAM, Ahmed MA. Constant hydraulic supply and ABA dynamics facilitate the trade-offs in water and carbon. FRONTIERS IN PLANT SCIENCE 2023; 14:1140938. [PMID: 37008480 PMCID: PMC10064056 DOI: 10.3389/fpls.2023.1140938] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/09/2023] [Accepted: 03/03/2023] [Indexed: 06/19/2023]
Abstract
Carbon-water trade-offs in plants are adjusted through stomatal regulation. Stomatal opening enables carbon uptake and plant growth, whereas plants circumvent drought by closing stomata. The specific effects of leaf position and age on stomatal behavior remain largely unknown, especially under edaphic and atmospheric drought. Here, we compared stomatal conductance (gs ) across the canopy of tomato during soil drying. We measured gas exchange, foliage ABA level and soil-plant hydraulics under increasing vapor pressure deficit (VPD). Our results indicate a strong effect of canopy position on stomatal behavior, especially under hydrated soil conditions and relatively low VPD. In wet soil (soil water potential > -50 kPa), upper canopy leaves had the highest gs (0.727 ± 0.154 mol m-2 s-1) and assimilation rate (A; 23.4 ± 3.9 µmol m-2 s-1) compared to the leaves at a medium height of the canopy (gs : 0.159 ± 0.060 mol m2 s-1; A: 15.9 ± 3.8 µmol m-2 s-1). Under increasing VPD (from 1.8 to 2.6 kPa), gs , A and transpiration were initially impacted by leaf position rather than leaf age. However, under high VPD (2.6 kPa), age effect outweighed position effect. The soil-leaf hydraulic conductance was similar in all leaves. Foliage ABA levels increased with rising VPD in mature leaves at medium height (217.56 ± 85 ng g-1 FW) compared to upper canopy leaves (85.36 ± 34 ng g-1 FW). Under soil drought (< -50 kPa), stomata closed in all leaves resulting in no differences in gs across the canopy. We conclude that constant hydraulic supply and ABA dynamics facilitate preferential stomatal behavior and carbon-water trade-offs across the canopy. These findings are fundamental in understanding variations within the canopy, which helps in engineering future crops, especially in the face of climate change.
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Affiliation(s)
- Mohanned Abdalla
- Department of Land, Air and Water Resources, University of California Davis, Davis, CA, United States
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
- Department of Horticulture, Faculty of Agriculture, University of Khartoum, Khartoum North, Sudan
- Chair of Soil-Root Interactions, TUM School of Life Science, Technical University of Munich, Freising, Germany
| | - Andreas H. Schweiger
- Institute of Landscape and Plant Ecology, Department of Plant Ecology, University of Hohenheim, Stuttgart, Germany
| | - Bernd J. Berauer
- Institute of Landscape and Plant Ecology, Department of Plant Ecology, University of Hohenheim, Stuttgart, Germany
| | - Scott A. M. McAdam
- Department of Botany and Plant Pathology, Purdue University, West Lafayette, IN, United States
| | - Mutez Ali Ahmed
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
- Chair of Soil-Root Interactions, TUM School of Life Science, Technical University of Munich, Freising, Germany
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11
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Busont O, Durambur G, Bernard S, Plasson C, Joudiou C, Baude L, Chefdor F, Depierreux C, Héricourt F, Larcher M, Malik S, Boulogne I, Driouich A, Carpin S, Lamblin F. Black Poplar (Populus nigra L.) Root Extracellular Trap, Structural and Molecular Remodeling in Response to Osmotic Stress. Cells 2023; 12:cells12060858. [PMID: 36980198 PMCID: PMC10047092 DOI: 10.3390/cells12060858] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/16/2023] [Revised: 03/04/2023] [Accepted: 03/06/2023] [Indexed: 03/12/2023] Open
Abstract
The root extracellular trap (RET) consists of root-associated, cap-derived cells (root AC-DCs) and their mucilaginous secretions, and forms a structure around the root tip that protects against biotic and abiotic stresses. However, there is little information concerning the changes undergone by the RET during droughts, especially for tree species. Morphological and immunocytochemical approaches were used to study the RET of black poplar (Populus nigra L.) seedlings grown in vitro under optimal conditions (on agar-gelled medium) or when polyethylene glycol-mediated (PEG6000—infused agar-gelled medium) was used to mimic drought conditions through osmotic stress. Under optimal conditions, the root cap released three populations of individual AC-DC morphotypes, with a very low proportion of spherical morphotypes, and equivalent proportions of intermediate and elongated morphotypes. Immunolabeling experiments using anti-glycan antibodies specific to cell wall polysaccharide and arabinogalactan protein (AGP) epitopes revealed the presence of homogalacturonan (HG), galactan chains of rhamnogalacturonan-I (RG-I), and AGPs in root AC-DC cell walls. The data also showed the presence of xylogalacturonan (XGA), xylan, AGPs, and low levels of arabinans in the mucilage. The findings also showed that under osmotic stress conditions, both the number of AC-DCs (spherical and intermediate morphotypes) and the total quantity of mucilage per root tip increased, whereas the mucilage was devoid of the epitopes associated with the polysaccharides RG-I, XGA, xylan, and AGPs. Osmotic stress also led to reduced root growth and increased root expression of the P5CS2 gene, which is involved in proline biosynthesis and cellular osmolarity maintenance (or preservation) in aerial parts. Together, our findings show that the RET is a dynamic structure that undergoes pronounced structural and molecular remodeling, which might contribute to the survival of the root tip under osmotic conditions.
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Affiliation(s)
- Océane Busont
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d’Orléans, INRAE, USC 1328, CEDEX 2, F-45067 Orléans, France
| | - Gaëlle Durambur
- GLYCOMEV UR 4358, SFR Normandie Végétal FED 4277, Innovation Chimie Carnot, University of Rouen Normandie, IRIB, F-76000 Rouen, France
| | - Sophie Bernard
- GLYCOMEV UR 4358, SFR Normandie Végétal FED 4277, Innovation Chimie Carnot, University of Rouen Normandie, IRIB, F-76000 Rouen, France
- INSERM, CNRS, HeRacLeS US 51 UAR 2026, PRIMACEN, University of Rouen Normandie, F-76000 Rouen, France
| | - Carole Plasson
- GLYCOMEV UR 4358, SFR Normandie Végétal FED 4277, Innovation Chimie Carnot, University of Rouen Normandie, IRIB, F-76000 Rouen, France
| | - Camille Joudiou
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d’Orléans, INRAE, USC 1328, CEDEX 2, F-45067 Orléans, France
| | - Laura Baude
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d’Orléans, INRAE, USC 1328, CEDEX 2, F-45067 Orléans, France
- Department of Biology, University of Fribourg, CH-1700 Fribourg, Switzerland
| | - Françoise Chefdor
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d’Orléans, INRAE, USC 1328, CEDEX 2, F-45067 Orléans, France
| | - Christiane Depierreux
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d’Orléans, INRAE, USC 1328, CEDEX 2, F-45067 Orléans, France
| | - François Héricourt
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d’Orléans, INRAE, USC 1328, CEDEX 2, F-45067 Orléans, France
| | - Mélanie Larcher
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d’Orléans, INRAE, USC 1328, CEDEX 2, F-45067 Orléans, France
| | - Sonia Malik
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d’Orléans, INRAE, USC 1328, CEDEX 2, F-45067 Orléans, France
| | - Isabelle Boulogne
- GLYCOMEV UR 4358, SFR Normandie Végétal FED 4277, Innovation Chimie Carnot, University of Rouen Normandie, IRIB, F-76000 Rouen, France
| | - Azeddine Driouich
- GLYCOMEV UR 4358, SFR Normandie Végétal FED 4277, Innovation Chimie Carnot, University of Rouen Normandie, IRIB, F-76000 Rouen, France
| | - Sabine Carpin
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d’Orléans, INRAE, USC 1328, CEDEX 2, F-45067 Orléans, France
| | - Frédéric Lamblin
- Laboratoire de Biologie des Ligneux et des Grandes Cultures, Université d’Orléans, INRAE, USC 1328, CEDEX 2, F-45067 Orléans, France
- Correspondence: ; Tel.: +33-(0)2-3841-7127
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12
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Koehler T, Schaum C, Tung SY, Steiner F, Tyborski N, Wild AJ, Akale A, Pausch J, Lueders T, Wolfrum S, Mueller CW, Vidal A, Vahl WK, Groth J, Eder B, Ahmed MA, Carminati A. Above and belowground traits impacting transpiration decline during soil drying in 48 maize (Zea mays) genotypes. ANNALS OF BOTANY 2023; 131:373-386. [PMID: 36479887 PMCID: PMC9992933 DOI: 10.1093/aob/mcac147] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/11/2022] [Revised: 11/24/2022] [Accepted: 12/06/2022] [Indexed: 06/17/2023]
Abstract
BACKGROUND AND AIMS Stomatal regulation allows plants to promptly respond to water stress. However, our understanding of the impact of above and belowground hydraulic traits on stomatal regulation remains incomplete. The objective of this study was to investigate how key plant hydraulic traits impact transpiration of maize during soil drying. We hypothesize that the stomatal response to soil drying is related to a loss in soil hydraulic conductivity at the root-soil interface, which in turn depends on plant hydraulic traits. METHODS We investigate the response of 48 contrasting maize (Zea mays) genotypes to soil drying, utilizing a novel phenotyping facility. In this context, we measure the relationship between leaf water potential, soil water potential, soil water content and transpiration, as well as root, rhizosphere and aboveground plant traits. KEY RESULTS Genotypes differed in their responsiveness to soil drying. The critical soil water potential at which plants started decreasing transpiration was related to a combination of above and belowground traits: genotypes with a higher maximum transpiration and plant hydraulic conductance as well as a smaller root and rhizosphere system closed stomata at less negative soil water potentials. CONCLUSIONS Our results demonstrate the importance of belowground hydraulics for stomatal regulation and hence drought responsiveness during soil drying. Furthermore, this finding supports the hypothesis that stomata start to close when soil hydraulic conductivity drops at the root-soil interface.
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Affiliation(s)
| | - Carolin Schaum
- Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Shu-Yin Tung
- Institute for Agroecology and Organic Farming, Bavarian State Research Center for Agriculture, Freising, Germany
| | | | - Nicolas Tyborski
- Ecological Microbiology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Andreas J Wild
- Agroecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Asegidew Akale
- Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Johanna Pausch
- Agroecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Tillmann Lueders
- Ecological Microbiology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Sebastian Wolfrum
- Institute for Agroecology and Organic Farming, Bavarian State Research Center for Agriculture, Freising, Germany
| | - Carsten W Mueller
- Soil Science, Technical University of Munich, Freising, Germany
- Department of Geosciences and Natural Resource Management, University of Copenhagen, Copenhagen, Denmark
| | - Alix Vidal
- Soil Biology Group, Wageningen University & Research, Wageningen, The Netherlands
| | - Wouter K Vahl
- Institute for Crop Science and Plant Breeding, Bavarian State Research Center for Agriculture, Freising, Germany
| | - Jennifer Groth
- Institute for Crop Science and Plant Breeding, Bavarian State Research Center for Agriculture, Freising, Germany
| | - Barbara Eder
- Institute for Crop Science and Plant Breeding, Bavarian State Research Center for Agriculture, Freising, Germany
| | - Mutez A Ahmed
- Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
- Department of Land, Air and Water Resources, University of California Davis, Davis, CA, USA
| | - Andrea Carminati
- Physics of Soils and Terrestrial Ecosystems, Department of Environmental Systems Science, ETH Zurich, Zurich, Switzerland
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13
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Zhang X, Bilyera N, Fan L, Duddek P, Ahmed MA, Carminati A, Kaestner A, Dippold MA, Spielvogel S, Razavi BS. The spatial distribution of rhizosphere microbial activities under drought: water availability is more important than root-hair-controlled exudation. THE NEW PHYTOLOGIST 2023; 237:780-792. [PMID: 35986650 DOI: 10.1111/nph.18409] [Citation(s) in RCA: 5] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Accepted: 07/22/2022] [Indexed: 06/15/2023]
Abstract
Root hairs and soil water content are crucial in controlling the release and diffusion of root exudates and shaping profiles of biochemical properties in the rhizosphere. But whether root hairs can offset the negative impacts of drought on microbial activity remains unknown. Soil zymography, 14 C imaging and neutron radiography were combined to identify how root hairs and soil moisture affect rhizosphere biochemical properties. To achieve this, we cultivated two maize genotypes (wild-type and root-hair-defective rth3 mutant) under ambient and drought conditions. Root hairs and optimal soil moisture increased hotspot area, rhizosphere extent and kinetic parameters (Vmax and Km ) of β-glucosidase activities. Drought enlarged the rhizosphere extent of root exudates and water content. Colocalization analysis showed that enzymatic hotspots were more colocalized with root exudate hotspots under optimal moisture, whereas they showed higher dependency on water hotspots when soil water and carbon were scarce. We conclude that root hairs are essential in adapting rhizosphere properties under drought to maintain plant nutrition when a continuous mass flow of water transporting nutrients to the root is interrupted. In the rhizosphere, soil water was more important than root exudates for hydrolytic enzyme activities under water and carbon colimitation.
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Affiliation(s)
- Xuechen Zhang
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, China
| | - Nataliya Bilyera
- Department of Soil and Plant Microbiome, Institute of Phytopathology, Christian-Albrechts University of Kiel, 24118, Kiel, Germany
- Department of Soil Science, Institute of Plant Nutrition and Soil Science, Christian-Albrechts University of Kiel, 24118, Kiel, Germany
- Geo-Biosphere Interactions, Department of Geosciences, University of Tuebingen, 72076, Tuebingen, Germany
| | - Lichao Fan
- College of Natural Resources and Environment, Northwest A&F University, Yangling, 712100, China
- Department of Soil Science of Temperate Ecosystems, University of Göttingen, 37077, Göttingen, Germany
| | - Patrick Duddek
- Department of Environmental Systems Science, Physics of Soils and Terrestrial Ecosystems, ETH Zürich, 8092, Zürich, Switzerland
- Division of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, 95440, Bayreuth, Germany
| | - Mutez A Ahmed
- Division of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, 95440, Bayreuth, Germany
- Department of Land, Air and Water Resources, University of California Davis, Davis, CA, 95616, USA
| | - Andrea Carminati
- Department of Environmental Systems Science, Physics of Soils and Terrestrial Ecosystems, ETH Zürich, 8092, Zürich, Switzerland
| | - Anders Kaestner
- Laboratory for Neutron Scattering and Imaging, Paul Scherrer Institute, 5232, Villigen, Switzerland
| | - Michaela A Dippold
- Geo-Biosphere Interactions, Department of Geosciences, University of Tuebingen, 72076, Tuebingen, Germany
- Biogeochemistry of Agroecosystems, University of Göttingen, 37077, Göttingen, Germany
| | - Sandra Spielvogel
- Department of Soil Science, Institute of Plant Nutrition and Soil Science, Christian-Albrechts University of Kiel, 24118, Kiel, Germany
| | - Bahar S Razavi
- Department of Soil and Plant Microbiome, Institute of Phytopathology, Christian-Albrechts University of Kiel, 24118, Kiel, Germany
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14
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Aslam MM, Karanja JK, Dodd IC, Waseem M, Weifeng X. Rhizosheath: An adaptive root trait to improve plant tolerance to phosphorus and water deficits? PLANT, CELL & ENVIRONMENT 2022; 45:2861-2874. [PMID: 35822342 PMCID: PMC9544408 DOI: 10.1111/pce.14395] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2022] [Revised: 07/07/2022] [Accepted: 07/11/2022] [Indexed: 06/09/2023]
Abstract
Drought and nutrient limitations adversely affect crop yields, with below-ground traits enhancing crop production in these resource-poor environments. This review explores the interacting biological, chemical and physical factors that determine rhizosheath (soil adhering to the root system) development, and its influence on plant water uptake and phosphorus acquisition in dry soils. Identification of quantitative trait loci for rhizosheath development indicate it is genetically determined, but the microbial community also directly (polysaccharide exudation) and indirectly (altered root hair development) affect its extent. Plants with longer and denser root hairs had greater rhizosheath development and increased P uptake efficiency. Moreover, enhanced rhizosheath formation maintains contact at the root-soil interface thereby assisting water uptake from drying soil, consequently improving plant survival in droughted environments. Nevertheless, it can be difficult to determine if rhizosheath development is a cause or consequence of improved plant adaptation to dry and nutrient-depleted soils. Does rhizosheath development directly enhance plant water and phosphorus use, or do other tolerance mechanisms allow plants to invest more resources in rhizosheath development? Much more work is required on the interacting genetic, physical, biochemical and microbial mechanisms that determine rhizosheath development, to demonstrate that selection for rhizosheath development is a viable crop improvement strategy.
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Affiliation(s)
- Mehtab Muhammad Aslam
- Center for Plant Water‐Use and Nutrition Regulation, College of Resource and EnvironmentFujian Agriculture and Forestry UniversityFuzhouFujianChina
- College of AgricultureYangzhou UniversityYangzhouJiangsuChina
- State Key Laboratory of Agrobiotechnology, School of Life SciencesThe Chinese University of Hong KongShatinHong Kong
| | - Joseph K. Karanja
- Center for Plant Water‐Use and Nutrition Regulation, College of Resource and EnvironmentFujian Agriculture and Forestry UniversityFuzhouFujianChina
| | - Ian C. Dodd
- The Lancaster Environment CentreLancaster UniversityLancasterUK
| | | | - Xu Weifeng
- Center for Plant Water‐Use and Nutrition Regulation, College of Resource and EnvironmentFujian Agriculture and Forestry UniversityFuzhouFujianChina
- College of AgricultureYangzhou UniversityYangzhouJiangsuChina
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15
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Brunn M, Hafner BD, Zwetsloot MJ, Weikl F, Pritsch K, Hikino K, Ruehr NK, Sayer EJ, Bauerle TL. Carbon allocation to root exudates is maintained in mature temperate tree species under drought. THE NEW PHYTOLOGIST 2022; 235:965-977. [PMID: 35403713 DOI: 10.1111/nph.18157] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Accepted: 04/04/2022] [Indexed: 06/14/2023]
Abstract
Carbon (C) exuded via roots is proposed to increase under drought and facilitate important ecosystem functions. However, it is unknown how exudate quantities relate to the total C budget of a drought-stressed tree, that is, how much of net-C assimilation is allocated to exudation at the tree level. We calculated the proportion of daily C assimilation allocated to root exudation during early summer by collecting root exudates from mature Fagus sylvatica and Picea abies exposed to experimental drought, and combining above- and belowground C fluxes with leaf, stem and fine-root surface area. Exudation from individual roots increased exponentially with decreasing soil moisture, with the highest increase at the wilting point. Despite c. 50% reduced C assimilation under drought, exudation from fine-root systems was maintained and trees exuded 1.0% (F. sylvatica) to 2.5% (P. abies) of net C into the rhizosphere, increasing the proportion of C allocation to exudates two- to three-fold. Water-limited P. abies released two-thirds of its exudate C into the surface soil, whereas in droughted F. sylvatica it was only one-third. Across the entire root system, droughted trees maintained exudation similar to controls, suggesting drought-imposed belowground C investment, which could be beneficial for ecosystem resilience.
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Affiliation(s)
- Melanie Brunn
- iES Landau, Institute for Environmental Sciences, University of Koblenz-Landau, 76829, Landau, Germany
| | - Benjamin D Hafner
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
| | - Marie J Zwetsloot
- Soil Biology Group, Wageningen University, 6708 PB, Wageningen, the Netherlands
| | - Fabian Weikl
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München GmbH - German Research Center for Environmental Health, 85764, Neuherberg, Germany
- TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Technical University of Munich, 85354, Freising, Germany
| | - Karin Pritsch
- Institute of Biochemical Plant Pathology, Helmholtz Zentrum München GmbH - German Research Center for Environmental Health, 85764, Neuherberg, Germany
| | - Kyohsuke Hikino
- TUM School of Life Sciences, Land Surface-Atmosphere Interactions, Ecophysiology of Plants, Technical University of Munich, 85354, Freising, Germany
| | - Nadine K Ruehr
- Institute of Meteorology and Climate Research - Atmospheric Environmental Research (IMK-IFU), Karlsruhe Institute of Technology (KIT), 82467, Garmisch-Partenkirchen, Germany
| | - Emma J Sayer
- Lancaster Environment Centre, Lancaster University, LA1 4YQ, Lancaster, UK
| | - Taryn L Bauerle
- School of Integrative Plant Science, Cornell University, Ithaca, NY, 14853, USA
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16
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Hallett PD, Marin M, Bending GD, George TS, Collins CD, Otten W. Building soil sustainability from root-soil interface traits. TRENDS IN PLANT SCIENCE 2022; 27:688-698. [PMID: 35168900 DOI: 10.1016/j.tplants.2022.01.010] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Revised: 01/06/2022] [Accepted: 01/20/2022] [Indexed: 06/14/2023]
Abstract
Great potential exists to harness plant traits at the root-soil interface, mainly rhizodeposition and root hairs, to 'build' soils with better structure that can trap more carbon and resources, resist climate stresses, and promote a healthy microbiome. These traits appear to have been preserved in modern crop varieties, but scope exists to improve them further because they vary considerably between genotypes and respond to environmental conditions. From emerging evidence, rhizodeposition can act as a disperser, aggregator, and/or hydrogel in soil, and root hairs expand rhizosheath size. Future research should explore impacts of selecting these traits on plants and soils concurrently, expanding from model plants to commercial genotypes, and observing whether impacts currently limited to glasshouse studies occur in the field.
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Affiliation(s)
- Paul D Hallett
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 3UU, UK.
| | - Maria Marin
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 3UU, UK
| | - Gary D Bending
- School of Life Sciences, University of Warwick, Coventry, CV4 7AL, UK
| | - Timothy S George
- Ecological Sciences Group, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA, UK
| | - Chris D Collins
- Department of Geography and Environmental Science, University of Reading, Reading RG6 6DW, UK
| | - Wilfred Otten
- Cranfield Soil and Agrifood Institute, College Road, Cranfield, MK43 0AL, UK
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17
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Omae N, Tsuda K. Plant-Microbiota Interactions in Abiotic Stress Environments. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2022; 35:511-526. [PMID: 35322689 DOI: 10.1094/mpmi-11-21-0281-fi] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
Abiotic stress adversely affects cellular homeostasis and ultimately impairs plant growth, posing a serious threat to agriculture. Climate change modeling predicts increasing occurrences of abiotic stresses such as drought and extreme temperature, resulting in decreasing the yields of major crops such as rice, wheat, and maize, which endangers food security for human populations. Plants are associated with diverse and taxonomically structured microbial communities that are called the plant microbiota. Plant microbiota often assist plant growth and abiotic stress tolerance by providing water and nutrients to plants and modulating plant metabolism and physiology and, thus, offer the potential to increase crop production under abiotic stress. In this review, we summarize recent progress on how abiotic stress affects plants, microbiota, plant-microbe interactions, and microbe-microbe interactions, and how microbes affect plant metabolism and physiology under abiotic stress conditions, with a focus on drought, salt, and temperature stress. We also discuss important steps to utilize plant microbiota in agriculture under abiotic stress.[Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Natsuki Omae
- State Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Hubei Key Lab of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
- Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Wuhan 430070, China
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
| | - Kenichi Tsuda
- State Key Laboratory of Agricultural Microbiology, Hubei Hongshan Laboratory, Hubei Key Lab of Plant Pathology, College of Plant Science and Technology, Huazhong Agricultural University, Wuhan 430070, China
- Shenzhen Institute of Nutrition and Health, Huazhong Agricultural University, Wuhan 430070, China
- Shenzhen Branch, Guangdong Laboratory of Lingnan Modern Agriculture, Genome Analysis Laboratory of the Ministry of Agriculture and Rural Affairs, Agricultural Genomics Institute at Shenzhen, Chinese Academy of Agricultural Sciences, Shenzhen 518120, China
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18
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Cai G, Ahmed MA. The role of root hairs in water uptake: recent advances and future perspectives. JOURNAL OF EXPERIMENTAL BOTANY 2022; 73:3330-3338. [PMID: 35323893 DOI: 10.1093/jxb/erac114] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 03/14/2022] [Indexed: 06/14/2023]
Abstract
Sufficient water is essential for plant growth and production. Root hairs connect roots to the soil, extend the effective root radius, and greatly enlarge the absorbing surface area. Although the efficacy of root hairs in nutrient uptake, especially phosphorus, has been well recognized, their role in water uptake remains contentious. Here we review recent advances in this field, discuss the factors affecting the role of root hairs in water uptake, and propose future directions. We argue that root hair length and shrinkage, in response to soil drying, explain the apparently contradictory evidence currently available. Our analysis revealed that shorter and vulnerable root hairs (i.e. rice and maize) made little, if any, contribution to root water uptake. In contrast, relatively longer root hairs (i.e. barley) had a clear influence on root water uptake, transpiration, and hence plant response to soil drying. We conclude that the role of root hairs in water uptake is species (and probably soil) specific. We propose that a holistic understanding of the efficacy of root hairs in water uptake will require detailed studies of root hair length, turnover, and shrinkage in different species and contrasting soil textures.
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Affiliation(s)
- Gaochao Cai
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, D-95444, Bayreuth, Germany
| | - Mutez Ali Ahmed
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, D-95444, Bayreuth, Germany
- Department of Land, Air and Water Resources, University of California Davis, Davis, CA 95616, USA
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19
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Yamanouchi H, Tokimura K, Miura N, Ikezawa K, Onjo M, Minami Y, Kajiya K. Effects of flooding cultivation on the composition and quality of taro (Colocasia esculenta cv. Daikichi). JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2022; 102:1372-1380. [PMID: 34363222 PMCID: PMC9291189 DOI: 10.1002/jsfa.11469] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/18/2021] [Revised: 07/17/2021] [Accepted: 08/06/2021] [Indexed: 06/13/2023]
Abstract
BACKGROUND Taro (Colocasia esculenta cv. Daikichi) is believed to be one of the earliest cultivated tuber crops and it is a staple food in many parts of the world. The mother corm and side cormels (daughter and granddaughter tubers) form the major consumed parts; however, the former is rarely preferred. Taro is mainly cultivated using either unflooded or flooding cultivation, under dryland-rainfed and wetland-irrigated conditions, respectively. Although flooding cultivation has several advantages, such as lower risk of diseases, weeds, and insect pests, contributing to increased tuber yield, its effects on the quality characteristics of the tubers are largely unknown. In this study, the effects of controlled flooding cultivation on the quality of mother corm and side cormels were investigated. Their taste, color, physical properties, antioxidant activity, and starch, oxalic acid, nitrate ion, arabinogalactan (AG)/AG protein (AGP), γ-aminobutyric acid (GABA), and total polyphenol content was compared with those under unflooded cultivation. RESULTS Flooding cultivation increased polyphenol levels and antioxidant activity and decreased oxalate, nitrate ion, GABA, and AG/AGP levels. Flooding cultivation also reduced the harshness and increased the hardness and stickiness of steamed mother corm paste, generally discarded under unflooded cultivation, thus rendering it suitable for consumption. CONCLUSION Controlled flooding cultivation has economic advantages and the potential to improve the quality of cultivated taro. © 2021 The Authors. Journal of The Science of Food and Agriculture published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Hiroki Yamanouchi
- Course of Biological Science & Technology, The United Graduate School of Agricultural SciencesKagoshima UniversityKagoshimaJapan
| | - Kanae Tokimura
- Kagoshima Prefectural Osumi Food Technology Development CenterKagoshimaJapan
| | - Nobuyuki Miura
- Kagoshima Prefectural Osumi Food Technology Development CenterKagoshimaJapan
| | - Kazuhiro Ikezawa
- Kagoshima Prefectural Institute for Agricultural DevelopmentMinamisatsumaJapan
| | - Michio Onjo
- Department of Agricultural Science & Natural Resources, Faculty of AgricultureKagoshima UniversityKagoshimaJapan
| | - Yuji Minami
- Course of Biological Science & Technology, The United Graduate School of Agricultural SciencesKagoshima UniversityKagoshimaJapan
| | - Katsuko Kajiya
- Course of Biological Science & Technology, The United Graduate School of Agricultural SciencesKagoshima UniversityKagoshimaJapan
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20
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Cai G, Ahmed MA, Abdalla M, Carminati A. Root hydraulic phenotypes impacting water uptake in drying soils. PLANT, CELL & ENVIRONMENT 2022; 45:650-663. [PMID: 35037263 PMCID: PMC9303794 DOI: 10.1111/pce.14259] [Citation(s) in RCA: 27] [Impact Index Per Article: 13.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2021] [Revised: 12/08/2021] [Accepted: 12/10/2021] [Indexed: 05/11/2023]
Abstract
Soil drying is a limiting factor for crop production worldwide. Yet, it is not clear how soil drying impacts water uptake across different soils, species, and root phenotypes. Here we ask (1) what root phenotypes improve the water use from drying soils? and (2) what root hydraulic properties impact water flow across the soil-plant continuum? The main objective is to propose a hydraulic framework to investigate the interplay between soil and root hydraulic properties on water uptake. We collected highly resolved data on transpiration, leaf and soil water potential across 11 crops and 10 contrasting soil textures. In drying soils, the drop in water potential at the soil-root interface resulted in a rapid decrease in soil hydraulic conductance, especially at higher transpiration rates. The analysis reveals that water uptake was limited by soil within a wide range of soil water potential (-6 to -1000 kPa), depending on both soil textures and root hydraulic phenotypes. We propose that a root phenotype with low root hydraulic conductance, long roots and/or long and dense root hairs postpones soil limitation in drying soils. The consequence of these root phenotypes on crop water use is discussed.
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Affiliation(s)
- Gaochao Cai
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER)University of BayreuthBayreuthGermany
| | - Mutez A. Ahmed
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER)University of BayreuthBayreuthGermany
- Department of Land, Air and Water ResourcesUniversity of California DavisDavisCaliforniaUnited States
| | - Mohanned Abdalla
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER)University of BayreuthBayreuthGermany
| | - Andrea Carminati
- Department of Environmental Systems Science, Physics of Soils and Terrestrial EcosystemsInstitute of Terrestrial Ecosystems, ETH ZürichZurichSwitzerland
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21
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Abdalla M, Ahmed MA. Arbuscular Mycorrhiza Symbiosis Enhances Water Status and Soil-Plant Hydraulic Conductance Under Drought. FRONTIERS IN PLANT SCIENCE 2021; 12:722954. [PMID: 34721455 PMCID: PMC8551442 DOI: 10.3389/fpls.2021.722954] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/09/2021] [Accepted: 09/20/2021] [Indexed: 05/27/2023]
Abstract
Recent studies have identified soil drying as a dominant driver of transpiration reduction at the global scale. Although Arbuscular Mycorrhiza Fungi (AMF) are assumed to play a pivotal role in plant response to soil drying, studies investigating the impact of AMF on plant water status and soil-plant hydraulic conductance are lacking. Thus, the main objective of this study was to investigate the influence of AMF on soil-plant conductance and plant water status of tomato under drought. We hypothesized that AMF limit the drop in matric potential across the rhizosphere, especially in drying soil. The underlying mechanism is that AMF extend the effective root radius and hence reduce the water fluxes at the root-soil interface. The follow-up hypothesis is that AMF enhance soil-plant hydraulic conductance and plant water status during soil drying. To test these hypotheses, we measured the relation between transpiration rate, soil and leaf water potential of tomato with reduced mycorrhiza colonization (RMC) and the corresponding wild type (WT). We inoculated the soil of the WT with Rhizophagus irregularis spores to potentially upsurge symbiosis initiation. During soil drying, leaf water potential of the WT did not drop below -0.8MPa during the first 6days after withholding irrigation, while leaf water potential of RMC dropped below -1MPa already after 4days. Furthermore, AMF enhanced the soil-plant hydraulic conductance of the WT during soil drying. In contrast, soil-plant hydraulic conductance of the RMC declined more abruptly as soil dried. We conclude that AMF maintained the hydraulic continuity between root and soil in drying soils, hereby reducing the drop in matric potential at the root-soil interface and enhancing soil-plant hydraulic conductance of tomato under edaphic stress. Future studies will investigate the role of AMF on soil-plant hydraulic conductance and plant water status among diverse plant species growing in contrasting soil textures.
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Affiliation(s)
- Mohanned Abdalla
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
- Department of Horticulture, Faculty of Agriculture, University of Khartoum, Khartoum North, Sudan
| | - Mutez Ali Ahmed
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
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22
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The Chemistry of Stress: Understanding the 'Cry for Help' of Plant Roots. Metabolites 2021; 11:metabo11060357. [PMID: 34199628 PMCID: PMC8228326 DOI: 10.3390/metabo11060357] [Citation(s) in RCA: 44] [Impact Index Per Article: 14.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2021] [Revised: 05/31/2021] [Accepted: 06/01/2021] [Indexed: 12/17/2022] Open
Abstract
Plants are faced with various biotic and abiotic stresses during their life cycle. To withstand these stresses, plants have evolved adaptive strategies including the production of a wide array of primary and secondary metabolites. Some of these metabolites can have direct defensive effects, while others act as chemical cues attracting beneficial (micro)organisms for protection. Similar to aboveground plant tissues, plant roots also appear to have evolved “a cry for help” response upon exposure to stress, leading to the recruitment of beneficial microorganisms to help minimize the damage caused by the stress. Furthermore, emerging evidence indicates that microbial recruitment to the plant roots is, at least in part, mediated by quantitative and/or qualitative changes in root exudate composition. Both volatile and water-soluble compounds have been implicated as important signals for the recruitment and activation of beneficial root-associated microbes. Here we provide an overview of our current understanding of belowground chemical communication, particularly how stressed plants shape its protective root microbiome.
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23
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Nazari M, Riebeling S, Banfield CC, Akale A, Crosta M, Mason-Jones K, Dippold MA, Ahmed MA. Mucilage Polysaccharide Composition and Exudation in Maize From Contrasting Climatic Regions. FRONTIERS IN PLANT SCIENCE 2020; 11:587610. [PMID: 33363554 PMCID: PMC7752898 DOI: 10.3389/fpls.2020.587610] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/26/2020] [Accepted: 11/18/2020] [Indexed: 05/28/2023]
Abstract
Mucilage, a gelatinous substance comprising mostly polysaccharides, is exuded by maize nodal and underground root tips. Although mucilage provides several benefits for rhizosphere functions, studies on the variation in mucilage amounts and its polysaccharide composition between genotypes are still lacking. In this study, eight maize (Zea mays L.) genotypes from different globally distributed agroecological zones were grown under identical abiotic conditions in a randomized field experiment. Mucilage exudation amount, neutral sugars and uronic acids were quantified. Galactose (∼39-42%), fucose (∼22-30%), mannose (∼11-14%), and arabinose (∼8-11%) were the major neutral sugars in nodal root mucilage. Xylose (∼1-4%), and glucose (∼1-4%) occurred only in minor proportions. Glucuronic acid (∼3-5%) was the only uronic acid detected. The polysaccharide composition differed significantly between maize genotypes. Mucilage exudation was 135 and 125% higher in the Indian (900 M Gold) and Kenyan (DH 02) genotypes than in the central European genotypes, respectively. Mucilage exudation was positively associated with the vapor pressure deficit of the genotypes' agroecological zone. The results indicate that selection for environments with high vapor pressure deficit may favor higher mucilage exudation, possibly because mucilage can delay the onset of hydraulic failure during periods of high vapor pressure deficit. Genotypes from semi-arid climates might offer sources of genetic material for beneficial mucilage traits.
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Affiliation(s)
- Meisam Nazari
- Division of Biogeochemistry of Agroecosystems, Georg-August University of Göttingen, Göttingen, Germany
| | - Sophie Riebeling
- Division of Biogeochemistry of Agroecosystems, Georg-August University of Göttingen, Göttingen, Germany
| | - Callum C. Banfield
- Division of Biogeochemistry of Agroecosystems, Georg-August University of Göttingen, Göttingen, Germany
| | - Asegidew Akale
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Margherita Crosta
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
| | - Kyle Mason-Jones
- Department of Terrestrial Ecology, Netherlands Institute of Ecology (NIOO-KNAW), Wageningen, Netherlands
| | - Michaela A. Dippold
- Division of Biogeochemistry of Agroecosystems, Georg-August University of Göttingen, Göttingen, Germany
| | - Mutez Ali Ahmed
- Division of Biogeochemistry of Agroecosystems, Georg-August University of Göttingen, Göttingen, Germany
- Chair of Soil Physics, Bayreuth Center of Ecology and Environmental Research (BayCEER), University of Bayreuth, Bayreuth, Germany
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24
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de Vries FT, Griffiths RI, Knight CG, Nicolitch O, Williams A. Harnessing rhizosphere microbiomes for drought-resilient crop production. Science 2020; 368:270-274. [PMID: 32299947 DOI: 10.1126/science.aaz5192] [Citation(s) in RCA: 252] [Impact Index Per Article: 63.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Root-associated microbes can improve plant growth, and they offer the potential to increase crop resilience to future drought. Although our understanding of the complex feedbacks between plant and microbial responses to drought is advancing, most of our knowledge comes from non-crop plants in controlled experiments. We propose that future research efforts should attempt to quantify relationships between plant and microbial traits, explicitly focus on food crops, and include longer-term experiments under field conditions. Overall, we highlight the need for improved mechanistic understanding of the complex feedbacks between plants and microbes during, and particularly after, drought. This requires integrating ecology with plant, microbiome, and molecular approaches and is central to making crop production more resilient to our future climate.
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Affiliation(s)
- Franciska T de Vries
- Department of Earth and Environmental Sciences, University of Manchester, Manchester M13 9PT, UK. .,Institute for Biodiversity and Ecosystem Dynamics, University of Amsterdam, 1090 GE Amsterdam, Netherlands
| | | | - Christopher G Knight
- Department of Earth and Environmental Sciences, University of Manchester, Manchester M13 9PT, UK
| | - Oceane Nicolitch
- Department of Earth and Environmental Sciences, University of Manchester, Manchester M13 9PT, UK
| | - Alex Williams
- Department of Earth and Environmental Sciences, University of Manchester, Manchester M13 9PT, UK
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25
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Ahn S, Lee SJ. Nano/Micro Natural Patterns of Hydrogels against Water Loss. ACS APPLIED BIO MATERIALS 2020; 3:1293-1304. [PMID: 35019330 DOI: 10.1021/acsabm.9b01177] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Water loss can be delayed by trapping it within a polymeric network, i.e. hydrogel. However, the dynamic response of natural materials has not been explained to maintain water levels relatively constant against varying environmental conditions. In this study, patterned polymeric materials formed on plant seeds are observed to provide effective water retention ability against repeated dehydration-rehydration procedures. The perpendicular line pattern (layer-by-layer stack) of the polymer films induces lateral line patterns (surface lines) by a typical wrinkling mechanism, which contributes to the characteristic water interaction. The anisotropic line patterns on the seed surface generate more hydrophilic properties over the isotropic patterns against drying-out. The matric potential (Ψm) of water through the line patterned gel matrix generally shows higher efficiency over isotropically patterned gels. Anisotropic lines (i.e., wrinkles) are one of the most abundant patterning procedures, thus they are a more advantageous function occurring in natural systems. This study sheds light on material design technologies to control water interaction in porous materials for various applications.
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Affiliation(s)
- Sungsook Ahn
- Berkeley Laboratory, Berkeley, California 94720, United States
| | - Sang Joon Lee
- Department of Mechanical Engineering, Pohang University of Science and Technology, Pohang 37673, Korea
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26
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Lapie C, Sterckeman T, Paris C, Leglize P. Impact of phenanthrene on primary metabolite profiling in root exudates and maize mucilage. ENVIRONMENTAL SCIENCE AND POLLUTION RESEARCH INTERNATIONAL 2020; 27:3124-3142. [PMID: 31838686 DOI: 10.1007/s11356-019-07298-x] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/18/2019] [Accepted: 12/04/2019] [Indexed: 06/10/2023]
Abstract
This study was conducted to assess the impact of polycyclic aromatic hydrocarbon on the composition of rhizodeposits. Maize was submitted to increasing phenanthrene (PHE) concentrations in the substrate (0, 25, 50, and 100 mg PHE.kg-1 of dry sand). After 6 weeks of cultivation, two types of rhizodeposit solution were collected. The first one, called rhizospheric sand extract, resulted from the extraction of root adhering sand in order to collect mucilage and associated compounds. The second one, the diffusate solution, was collected by the diffusion of exudates from roots soaked in water. The impact of phenanthrene on maize morphology and functioning was measured prior to the analysis of the main components of the rhizodeposit solutions, by measuring total carbon, protein, amino acid, and sugars as well as by determining about 40 compounds using GC-MS and LC-MS. As maize exposure to PHE increased, different trends were observed in the two rhizodeposit solutions. In the diffusate solution, we measured a global increase of metabolites exudation like carbohydrates, amino acids, and proteins except for some monoglycerides and organic acids which exudation decreased in the presence of PHE. In the rhizospheric sand extract, we witnessed a decrease in carbohydrates and amino acids secretion as well as in fatty and organic acids when plants were exposed to PHE. Many of the compounds measured, like organic acids, carbohydrates, amino acids, or fatty acids, could directly or indirectly drive PAHs availability in soils with particular consequences for their degradation.
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Affiliation(s)
- Clémentine Lapie
- Inrae, Laboratoire Sols et Environnement, Université de Lorraine, F-54000, Nancy, France
| | - Thibault Sterckeman
- Inrae, Laboratoire Sols et Environnement, Université de Lorraine, F-54000, Nancy, France
| | - Cédric Paris
- Laboratoire d'Ingénierie des Biomolécules, Université de Lorraine, F-54000, Nancy, France
- Plateau d'Analyse Structurale et Métabolomique, SF4242, EFABA, Université de Lorraine, Vandœuvre-lès-Nancy, France
| | - Pierre Leglize
- Inrae, Laboratoire Sols et Environnement, Université de Lorraine, F-54000, Nancy, France.
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27
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Ruiz S, Koebernick N, Duncan S, Fletcher DM, Scotson C, Boghi A, Marin M, Bengough AG, George TS, Brown LK, Hallett PD, Roose T. Significance of root hairs at the field scale - modelling root water and phosphorus uptake under different field conditions. PLANT AND SOIL 2019; 447:281-304. [PMID: 32214504 PMCID: PMC7062663 DOI: 10.1007/s11104-019-04308-2] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2019] [Accepted: 09/13/2019] [Indexed: 05/22/2023]
Abstract
ABSTRACT BACKGROUND AND AIMS Root hairs play a significant role in phosphorus (P) extraction at the pore scale. However, their importance at the field scale remains poorly understood. METHODS This study uses a continuum model to explore the impact of root hairs on the large-scale uptake of P, comparing root hair influence under different agricultural scenarios. High vs low and constant vs decaying P concentrations down the soil profile are considered, along with early vs late precipitation scenarios. RESULTS Simulation results suggest root hairs accounted for 50% of total P uptake by plants. Furthermore, a delayed initiation time of precipitation potentially limits the P uptake rate by over 50% depending on the growth period. Despite the large differences in the uptake rate, changes in the soil P concentration in the domain due to root solute uptake remains marginal when considering a single growth season. However, over the duration of 6 years, simulation results showed that noticeable differences arise over time. CONCLUSION Root hairs are critical to P capture, with uptake efficiency potentially enhanced by coordinating irrigation with P application during earlier growth stages of crops.
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Affiliation(s)
- S Ruiz
- 1Bioengineering Science Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Science, University of Southampton, Southampton, SO17 1BJ UK
| | - N Koebernick
- 1Bioengineering Science Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Science, University of Southampton, Southampton, SO17 1BJ UK
- 5Institute of Agricultural and Nutritional Sciences, Martin Luther University Halle-Wittenberg, Universitaetplatz 10, 06108 Halle (Saale), Germany
| | - S Duncan
- 1Bioengineering Science Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Science, University of Southampton, Southampton, SO17 1BJ UK
| | - D McKay Fletcher
- 1Bioengineering Science Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Science, University of Southampton, Southampton, SO17 1BJ UK
| | - C Scotson
- 1Bioengineering Science Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Science, University of Southampton, Southampton, SO17 1BJ UK
| | - A Boghi
- 1Bioengineering Science Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Science, University of Southampton, Southampton, SO17 1BJ UK
| | - M Marin
- 2School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 3UU UK
| | - A G Bengough
- 3Ecological Sciences Group, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA UK
- 4School of Science and Engineering, University of Dundee, Dundee, DD1 4HN UK
| | - T S George
- 3Ecological Sciences Group, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA UK
| | - L K Brown
- 3Ecological Sciences Group, The James Hutton Institute, Invergowrie, Dundee, DD2 5DA UK
| | - P D Hallett
- 2School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 3UU UK
| | - T Roose
- 1Bioengineering Science Research Group, Department of Mechanical Engineering, School of Engineering, Faculty of Engineering and Physical Science, University of Southampton, Southampton, SO17 1BJ UK
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28
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Passot S, Couvreur V, Meunier F, Draye X, Javaux M, Leitner D, Pagès L, Schnepf A, Vanderborght J, Lobet G. Connecting the dots between computational tools to analyse soil-root water relations. JOURNAL OF EXPERIMENTAL BOTANY 2019; 70:2345-2357. [PMID: 30329081 DOI: 10.1093/jxb/ery361] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/07/2018] [Accepted: 10/10/2018] [Indexed: 05/20/2023]
Abstract
In recent years, many computational tools, such as image analysis, data management, process-based simulation, and upscaling tools, have been developed to help quantify and understand water flow in the soil-root system, at multiple scales (tissue, organ, plant, and population). Several of these tools work together or at least are compatible. However, for the uninformed researcher, they might seem disconnected, forming an unclear and disorganized succession of tools. In this article, we show how different studies can be further developed by connecting them to analyse soil-root water relations in a comprehensive and structured network. This 'explicit network of soil-root computational tools' informs readers about existing tools and helps them understand how their data (past and future) might fit within the network. We also demonstrate the novel possibilities of scale-consistent parameterizations made possible by the network with a set of case studies from the literature. Finally, we discuss existing gaps in the network and how we can move forward to fill them.
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Affiliation(s)
- Sixtine Passot
- Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Valentin Couvreur
- Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Félicien Meunier
- Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
- Computational and Applied Vegetation Ecology lab, Ghent University, Gent, Belgium
- Department of Earth and Environment, Boston University, Boston, MA, USA
| | - Xavier Draye
- Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
| | - Mathieu Javaux
- Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
- Agrosphere, IBG3, Forschungszentrum Jülich, GmbH Jülich, Germany
| | | | | | - Andrea Schnepf
- Agrosphere, IBG3, Forschungszentrum Jülich, GmbH Jülich, Germany
| | - Jan Vanderborght
- Agrosphere, IBG3, Forschungszentrum Jülich, GmbH Jülich, Germany
| | - Guillaume Lobet
- Earth and Life Institute, Université catholique de Louvain, Louvain-la-Neuve, Belgium
- Agrosphere, IBG3, Forschungszentrum Jülich, GmbH Jülich, Germany
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29
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Naveed M, Ahmed MA, Benard P, Brown LK, George TS, Bengough AG, Roose T, Koebernick N, Hallett PD. Surface tension, rheology and hydrophobicity of rhizodeposits and seed mucilage influence soil water retention and hysteresis. PLANT AND SOIL 2019; 437:65-81. [PMID: 31007286 PMCID: PMC6447521 DOI: 10.1007/s11104-019-03939-9] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Accepted: 01/08/2019] [Indexed: 06/01/2023]
Abstract
AIMS Rhizodeposits collected from hydroponic solutions with roots of maize and barley, and seed mucilage washed from chia, were added to soil to measure their impact on water retention and hysteresis in a sandy loam soil at a range of concentrations. We test the hypothesis that the effect of plant exudates and mucilages on hydraulic properties of soils depends on their physicochemical characteristics and origin. METHODS Surface tension and viscosity of the exudate solutions were measured using the Du Noüy ring method and a cone-plate rheometer, respectively. The contact angle of water on exudate treated soil was measured with the sessile drop method. Water retention and hysteresis were measured by equilibrating soil samples, treated with exudates and mucilages at 0.46 and 4.6 mg g-1 concentration, on dialysis tubing filled with polyethylene glycol (PEG) solution of known osmotic potential. RESULTS Surface tension decreased and viscosity increased with increasing concentration of the exudates and mucilage in solutions. Change in surface tension and viscosity was greatest for chia seed exudate and least for barley root exudate. Contact angle increased with increasing maize root and chia seed exudate concentration in soil, but not barley root. Chia seed mucilage and maize root rhizodeposits enhanced soil water retention and increased hysteresis index, whereas barley root rhizodeposits decreased soil water retention and the hysteresis effect. The impact of exudates and mucilages on soil water retention almost ceased when approaching wilting point at -1500 kPa matric potential. CONCLUSIONS Barley rhizodeposits behaved as surfactants, drying the rhizosphere at smaller suctions. Chia seed mucilage and maize root rhizodeposits behaved as hydrogels that hold more water in the rhizosphere, but with slower rewetting and greater hysteresis.
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Affiliation(s)
- M. Naveed
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 3UU UK
- School of Computing and Engineering, University of West London, Ealing London, W5 5RF UK
| | - M. A. Ahmed
- Faculty of Biology, Chemistry and Earth Sciences, University of Bayreuth, Bayreuth, Germany
| | - P. Benard
- Faculty of Biology, Chemistry and Earth Sciences, University of Bayreuth, Bayreuth, Germany
| | - L. K. Brown
- The James Hutton Institute, Invergowrie, Dundee, DD2 5DA UK
| | - T. S. George
- The James Hutton Institute, Invergowrie, Dundee, DD2 5DA UK
| | - A. G. Bengough
- The James Hutton Institute, Invergowrie, Dundee, DD2 5DA UK
- School of Science and Engineering, University of Dundee, Dundee, DD1 4HN UK
| | - T. Roose
- Faculty of Engineering and Environment, University of Southampton, Southampton, SO17 1BJ UK
| | - N. Koebernick
- Faculty of Engineering and Environment, University of Southampton, Southampton, SO17 1BJ UK
| | - P. D. Hallett
- School of Biological Sciences, University of Aberdeen, Aberdeen, AB24 3UU UK
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30
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Gargallo-Garriga A, Preece C, Sardans J, Oravec M, Urban O, Peñuelas J. Root exudate metabolomes change under drought and show limited capacity for recovery. Sci Rep 2018; 8:12696. [PMID: 30140025 PMCID: PMC6107494 DOI: 10.1038/s41598-018-30150-0] [Citation(s) in RCA: 115] [Impact Index Per Article: 19.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/06/2018] [Accepted: 07/10/2018] [Indexed: 11/10/2022] Open
Abstract
Root exudates comprise a large variety of compounds released by plants into the rhizosphere, including low-molecular-weight primary metabolites (particularly saccharides, amino acids and organic acids) and secondary metabolites (phenolics, flavonoids and terpenoids). Changes in exudate composition could have impacts on the plant itself, on other plants, on soil properties (e.g. amount of soil organic matter), and on soil organisms. The effects of drought on the composition of root exudates, however, have been rarely studied. We used an ecometabolomics approach to identify the compounds in the exudates of Quercus ilex (holm oak) under an experimental drought gradient and subsequent recovery. Increasing drought stress strongly affected the composition of the exudate metabolome. Plant exudates under drought consisted mainly of secondary metabolites (71% of total metabolites) associated with plant responses to drought stress, whereas the metabolite composition under recovery shifted towards a dominance of primary metabolites (81% of total metabolites). These results strongly suggested that roots exude the most abundant root metabolites. The exudates were changed irreversibly by the lack of water under extreme drought conditions, and the plants could not recover.
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Affiliation(s)
- Albert Gargallo-Garriga
- CSIC, Global Ecology Unit CREAF- CSIC-UAB, Bellaterra, 08193, Catalonia, Spain.
- CREAF, Cerdanyola del Vallès, 08193, Catalonia, Spain.
- Global Change Research Institute, The Czech Academy of Sciences, Belidla 986/4a, CZ-60300, Brno, Czech Republic.
| | - Catherine Preece
- CSIC, Global Ecology Unit CREAF- CSIC-UAB, Bellaterra, 08193, Catalonia, Spain
- CREAF, Cerdanyola del Vallès, 08193, Catalonia, Spain
| | - Jordi Sardans
- CSIC, Global Ecology Unit CREAF- CSIC-UAB, Bellaterra, 08193, Catalonia, Spain
- CREAF, Cerdanyola del Vallès, 08193, Catalonia, Spain
| | - Michal Oravec
- Global Change Research Institute, The Czech Academy of Sciences, Belidla 986/4a, CZ-60300, Brno, Czech Republic
| | - Otmar Urban
- Global Change Research Institute, The Czech Academy of Sciences, Belidla 986/4a, CZ-60300, Brno, Czech Republic
| | - Josep Peñuelas
- CSIC, Global Ecology Unit CREAF- CSIC-UAB, Bellaterra, 08193, Catalonia, Spain
- CREAF, Cerdanyola del Vallès, 08193, Catalonia, Spain
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31
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Rabbi SMF, Tighe MK, Flavel RJ, Kaiser BN, Guppy CN, Zhang X, Young IM. Plant roots redesign the rhizosphere to alter the three-dimensional physical architecture and water dynamics. THE NEW PHYTOLOGIST 2018; 219:542-550. [PMID: 29774952 DOI: 10.1111/nph.15213] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/13/2017] [Accepted: 04/01/2018] [Indexed: 05/13/2023]
Abstract
The mechanisms controlling the genesis of rhizosheaths are not well understood, despite their importance in controlling the flux of nutrients and water from soil to root. Here, we examine the development of rhizosheaths from drought-tolerant and drought-sensitive chickpea varieties; focusing on the three-dimensional characterization of the pore volume (> 16 μm voxel spatial resolution) obtained from X-ray microtomography, along with the characterization of mucilage and root hairs, and water sorption. We observe that drought-tolerant plants generate a larger diameter root, and a greater and more porous mass of rhizosheath, which also has a significantly increased water sorptivity, as compared with bulk soil. Using lattice Boltzmann simulations of soil permeability, we find that the root activity of both cultivars creates an anisotropic structure in the rhizosphere, in that its ability to conduct water in the radial direction is significantly higher than in the axial direction, especially in the drought-tolerant cultivar. We suggest that significant differences in rhizosheath architectures are sourced not only by changes in structure of the volumes, but also from root mucilage, and further suggest that breeding for rhizosheath architectures and function may be a potential future avenue for better designing crops in a changing environment.
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Affiliation(s)
- Sheikh M F Rabbi
- School of Life and Environmental Sciences, ARC Industrial Transformation Research Hub - Legumes for Sustainable Agriculture, University of Sydney, Camperdown, Sydney, NSW, 2006, Australia
| | - Matthew K Tighe
- School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Richard J Flavel
- School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Brent N Kaiser
- School of Life and Environmental Sciences, ARC Industrial Transformation Research Hub - Legumes for Sustainable Agriculture, University of Sydney, Camperdown, Sydney, NSW, 2006, Australia
| | - Chris N Guppy
- School of Environmental and Rural Science, University of New England, Armidale, NSW, 2351, Australia
| | - Xiaoxian Zhang
- Rothamsted Research, Sustainable Agriculture Sciences, Harpenden, Hertfordshire, AL 5 2JQ, UK
| | - Iain M Young
- School of Life and Environmental Sciences, ARC Industrial Transformation Research Hub - Legumes for Sustainable Agriculture, University of Sydney, Camperdown, Sydney, NSW, 2006, Australia
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Gavrichkova O, Liberati D, de Dato G, Abou Jaoudé R, Brugnoli E, de Angelis P, Guidolotti G, Pausch J, Spohn M, Tian J, Kuzyakov Y. Effects of rain shortage on carbon allocation, pools and fluxes in a Mediterranean shrub ecosystem - a 13C labelling field study. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 627:1242-1252. [PMID: 30857089 DOI: 10.1016/j.scitotenv.2018.01.311] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/14/2017] [Revised: 01/29/2018] [Accepted: 01/29/2018] [Indexed: 06/09/2023]
Abstract
Hydrological cycle is expected to become the primary cause of ecosystem's degradation in near future under changing climate. Rain manipulation experiments under field conditions provide accurate picture on the responses of biotic processes to changed water availability for plants. A field experiment, mimicking expected changes in rain patterns, was established in a Mediterranean shrub community at Porto Conte, Italy, in 2001. In November 2011 Cistus monspeliensis, one of the dominating shrub species in the Mediterranean basin, was 13C labelled on plots subjected to extended rain shortage period and on control non manipulated plots. Carbon (C) allocation was traced by 13C dynamics in shoots, shoot-respired CO2, roots, microbial biomass, K2SO4-extractable C and CO2 respired from soil. Most of the recovered 13C (60%) was respired by shoots within 2weeks in control plots. In rain shortage treatment, 13C remained incorporated in aboveground plant parts. Residence time of 13C in leaves was longer under the rain shortage because less 13C was lost by shoot respiration and because 13C was re-allocated to leaves from woody tissues. The belowground C sink was weak (3-4% of recovered 13C) and independent on rain manipulation. Extended rain shortage promoted C exudation into rhizosphere soil in expense of roots. Together with lowered photosynthesis, this "save" economy of new C metabolites reduces the growing season under rain shortage resulting in decrease of shrub cover and C losses from the system on the long-term.
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Affiliation(s)
- Olga Gavrichkova
- Institute of Agro Environmental and Forest Biology, National Research Council, Porano 05010, Monterotondo Scalo 00015 and Cinte Tesino 38050, Italy; Peoples Friendship University of Russia (RUDN University), 117198 Moscow, Russian Federation.
| | - Dario Liberati
- Department for Innovation in Biological, Agro-food and Forest Systems, University of Tuscia, Viterbo 01100, Italy
| | - Giovanbattista de Dato
- Council for Agricultural Research and Economics (CREA) - Research Centre for Forestry and Wood, 52100 Arezzo, Italy
| | - Renée Abou Jaoudé
- Department for Innovation in Biological, Agro-food and Forest Systems, University of Tuscia, Viterbo 01100, Italy
| | - Enrico Brugnoli
- Institute of Agro Environmental and Forest Biology, National Research Council, Porano 05010, Monterotondo Scalo 00015 and Cinte Tesino 38050, Italy
| | - Paolo de Angelis
- Department for Innovation in Biological, Agro-food and Forest Systems, University of Tuscia, Viterbo 01100, Italy
| | - Gabriele Guidolotti
- Institute of Agro Environmental and Forest Biology, National Research Council, Porano 05010, Monterotondo Scalo 00015 and Cinte Tesino 38050, Italy
| | - Johanna Pausch
- Department of Soil Science of Temperate Ecosystems, University of Göttingen, Göttingen 37077, Germany; Department of Agricultural Soil Science, University of Göttingen, Göttingen 37077, Germany
| | - Marie Spohn
- Department of Soil Ecology, Bayreuth Center of Ecology and Environmental Research (BayCEER), University Bayreuth, Germany
| | - Jing Tian
- Department of Soil Science of Temperate Ecosystems, University of Göttingen, Göttingen 37077, Germany; Key Laboratory of Ecosystem Network Observation and Modeling, Institute of Geographic Sciences and Natural Resources Research, Chinese Academy of Sciences (CAS), 100101 Beijing, China; Department of Agricultural Soil Science, University of Göttingen, Göttingen 37077, Germany
| | - Yakov Kuzyakov
- Department of Soil Science of Temperate Ecosystems, University of Göttingen, Göttingen 37077, Germany; Peoples Friendship University of Russia (RUDN University), 117198 Moscow, Russian Federation; Institute of Environmental Sciences, Kazan Federal University, 420049 Kazan, Russian Federation; Department of Agricultural Soil Science, University of Göttingen, Göttingen 37077, Germany
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Ahmed MA, Passioura J, Carminati A. Hydraulic processes in roots and the rhizosphere pertinent to increasing yield of water-limited grain crops: a critical review. JOURNAL OF EXPERIMENTAL BOTANY 2018; 69:3255-3265. [PMID: 29767797 DOI: 10.1093/jxb/ery183] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 05/10/2018] [Indexed: 06/08/2023]
Abstract
A review of the role of roots in extracting water from the soil with regard to amount and timing leading to maximal grain yield, and of the various mechanisms underlying this.
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Affiliation(s)
- Mutez Ali Ahmed
- Chair of Soil Physics, University of Bayreuth, Bayreuth, Germany
- Division of Soil Hydrology, Georg-August University of Goettingen, Goettingen, Germany
| | | | - Andrea Carminati
- Chair of Soil Physics, University of Bayreuth, Bayreuth, Germany
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Di Marsico A, Scrano L, Amato M, Gàmiz B, Real M, Cox L. Mucilage from seeds of chia (Salvia hispanica L.) used as soil conditioner; effects on the sorption-desorption of four herbicides in three different soils. THE SCIENCE OF THE TOTAL ENVIRONMENT 2018; 625:531-538. [PMID: 29291567 DOI: 10.1016/j.scitotenv.2017.12.078] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/2017] [Revised: 12/03/2017] [Accepted: 12/04/2017] [Indexed: 05/27/2023]
Abstract
The objective of this work was to determine the effect of the mucilage extracted from Chia seeds (Salvia hispanica L.) as soil amendment on soil physical properties and on the sorption-desorption behaviour of four herbicides (MCPA, Diuron, Clomazone and Terbuthylazine) used in cereal crops. Three soils of different texture (sandy-loam, loam and clay-loam) were selected, and mercury intrusion porosimetry and surface area analysis were used to examine changes in the microstructural characteristics caused by the reactions that occur between the mucilage and soil particles. Laboratory studies were conducted to characterise the selected herbicides with regard their sorption on tested soils added or not with the mucilage. Mucilage amendment resulted in a reduction in soil porosity, basically due to a reduction in larger pores (radius>10μm) and an important increase in finer pores (radius<10μm) and in partcles' surface. A higher herbicide sorption in the amended soils was ascertained when compared to unamended soils. The sorption percentage of herbicides in soils treated with mucilage increased in the order; sandy-loam<loam<clay-loam. The increase in the organic carbon content upon amendment and the natural clay content of the soils are revealed to be responsible for the higher adsorption of Diuron when compared with Terbuthylazine, Clomazone and MCPA. Desorption of the herbicides was highly inhibited in the soils treated with mucilage; only Terbuthylazine showed a slight desorption in the case of loam and clay loam-soils. This study leads to the conclusion that mucilage from Chia seeds used as soil conditioner can reduce the mobility of herbicides tested in agricultural soils with different physico-chemical properties.
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Affiliation(s)
- A Di Marsico
- SAFE, University of Basilicata, V.le dell'Ateneo Lucano N° 10 c.a.p., 85100 Potenza, Italy.
| | - L Scrano
- DICEM, University of Basilicata, V.le dell'Ateneo Lucano N° 10 c.a.p., 85100 Potenza, Italy.
| | - M Amato
- SAFE, University of Basilicata, V.le dell'Ateneo Lucano N° 10 c.a.p., 85100 Potenza, Italy.
| | - B Gàmiz
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNASE-CSIC), P.O. Box 1052, 41080 Sevilla, Spain.
| | - M Real
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNASE-CSIC), P.O. Box 1052, 41080 Sevilla, Spain.
| | - L Cox
- Instituto de Recursos Naturales y Agrobiología de Sevilla (IRNASE-CSIC), P.O. Box 1052, 41080 Sevilla, Spain.
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Preece C, Farré-Armengol G, Llusià J, Peñuelas J. Thirsty tree roots exude more carbon. TREE PHYSIOLOGY 2018; 38:690-695. [PMID: 29304257 DOI: 10.1093/treephys/tpx163] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/04/2017] [Accepted: 11/16/2017] [Indexed: 05/07/2023]
Abstract
Root exudation is an important input of carbon into soils and affects plant and soil communities, but little is known about the effect of climatic factors such as drought on exudation, and its ability to recover. We studied the impact of increasing drought on root exudation and its subsequent recovery in the Mediterranean tree species Quercus ilex L. in a greenhouse study by measuring the amount of total organic carbon in exudates. The amount of exudation per unit root area increased with drought duration and was 21% higher under the most extreme drought scenario compared with the non-droughted control. The amount of root exudation did not differ between the treatments following 6 weeks of re-watering, indicating a strong capacity for recovery in this species. We concluded that drought could affect the amount of root exudation, which could in turn have a large impact on microbial activity in the rhizosphere, and alter these microbial communities, at least in the short term. This tree species may be able to return to normal levels of root exudation after a drought event, but long-term exudate-mediated impacts on Mediterranean forest soils may be an unforeseen effect of drought.
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Affiliation(s)
- Catherine Preece
- CREAF, Cerdanyola del Vallès, 08193, Spain
- CSIC Global Ecology Unit, CREAF-CSIC-UAB, Bellaterra 08193, Spain
| | - Gerard Farré-Armengol
- CREAF, Cerdanyola del Vallès, 08193, Spain
- CSIC Global Ecology Unit, CREAF-CSIC-UAB, Bellaterra 08193, Spain
| | - Joan Llusià
- CREAF, Cerdanyola del Vallès, 08193, Spain
- CSIC Global Ecology Unit, CREAF-CSIC-UAB, Bellaterra 08193, Spain
| | - Josep Peñuelas
- CREAF, Cerdanyola del Vallès, 08193, Spain
- CSIC Global Ecology Unit, CREAF-CSIC-UAB, Bellaterra 08193, Spain
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Choudhury BU, Ferraris S, Ashton RW, Powlson DS, Whalley WR. The effect of microbial activity on soil water diffusivity. EUROPEAN JOURNAL OF SOIL SCIENCE 2018; 69:407-413. [PMID: 29937684 PMCID: PMC5993228 DOI: 10.1111/ejss.12535] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/29/2017] [Revised: 11/13/2017] [Accepted: 11/22/2017] [Indexed: 05/18/2023]
Abstract
In this study, we explored the effects of microbial activity on the evaporation of water from cores of a sandy soil under laboratory conditions. We applied treatments to stimulate microbial activity by adding different amounts of synthetic analogue root exudates. For comparison, we used soil samples without synthetic root exudates as control and samples treated with mercuric chloride to suppress microbial activity. Our results suggest that increasing microbial activity reduces the rate of evaporation from soil. Estimated diffusivities in soil with the largest amounts of added root exudates were one third of those estimated in samples where microbial activity was suppressed by adding mercuric chloride. We discuss the effect of our results with respect to water uptake by roots. HIGHLIGHTS We explored effects of microbial activity on the evaporation of water from cores of a sandy soil.We found the effect of microbial activity on water release characteristic was small.Increasing microbial activity reduced evaporation from soil, while microbial suppression increased it.Effect of microbial activity on root water uptake was estimated to be equivalent to a change in soil structure.
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Affiliation(s)
- B. U. Choudhury
- Department of Sustainable Agricultural SciencesRothamsted ResearchHarpenden AL5 2JQUK
- Division of Natural Resource ManagementICAR (RC) for NEH Region, Umiam, Ri‐BhoiMeghalaya 793 103India
| | - S. Ferraris
- Politecnico and University of TorinoInteruniversity Department of Regional and Urban Studies and Planning, Viale Mattioli 39TorinoItaly
| | - R. W. Ashton
- Department of Sustainable Agricultural SciencesRothamsted ResearchHarpenden AL5 2JQUK
| | - D. S. Powlson
- Department of Sustainable Agricultural SciencesRothamsted ResearchHarpenden AL5 2JQUK
| | - W. R. Whalley
- Department of Sustainable Agricultural SciencesRothamsted ResearchHarpenden AL5 2JQUK
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Gaion LA, Monteiro CC, Cruz FJR, Rossatto DR, López-Díaz I, Carrera E, Lima JE, Peres LEP, Carvalho RF. Constitutive gibberellin response in grafted tomato modulates root-to-shoot signaling under drought stress. JOURNAL OF PLANT PHYSIOLOGY 2018; 221:11-21. [PMID: 29223878 DOI: 10.1016/j.jplph.2017.12.003] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/12/2017] [Revised: 11/21/2017] [Accepted: 12/02/2017] [Indexed: 05/07/2023]
Abstract
Plants are sessile organisms that must perceive and respond to various environmental constraints throughout their life cycle. Among these constraints, drought stress has become the main limiting factor to crop production around the world. Water deprivation is perceived primarily by the roots, which efficiently signal the shoot to trigger drought responses in order to maximize a plant's ability to survive. In this study, the tomato (Solanum lycopersicum L.) mutant procera (pro), with a constitutive response to gibberellin (GA), and its near isogenic line cv. Micro-Tom (MT), were used in reciprocal grafting under well-watered and water stress conditions to evaluate the role of GA signaling in root-to-shoot communication during drought stress. Growth, oxidative stress, gene expression, water relations and hormonal content were measured in order to provide insights into GA-mediated adjustments to water stress. All graft combinations with pro (i.e. pro/pro, MT/pro and pro/MT) prevented the reduction of growth under stress conditions without a reduction in oxidative stress. The increase of oxidative stress was followed by upregulation of SlDREB2, a drought-tolerance related gene, in all drought-stressed plants. Scions harboring the pro mutation tended to increase the abscisic acid (ABA) content, independent of the rootstock. Moreover, the GA sensitivity of the rootstock modulated stomatal conductance and water use efficiency under drought stress, indicating GA and ABA crosstalk in the adjustment of growth and water economy.
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Affiliation(s)
- Lucas Aparecido Gaion
- Department of Biology Applied to Agriculture, São Paulo State University, Via de Acesso Prof. Paulo Donato Castellane, 14884-900, Jaboticabal, Brazil
| | - Carolina Cristina Monteiro
- Department of Biology Applied to Agriculture, São Paulo State University, Via de Acesso Prof. Paulo Donato Castellane, 14884-900, Jaboticabal, Brazil
| | - Flávio José Rodrigues Cruz
- Department of Biology Applied to Agriculture, São Paulo State University, Via de Acesso Prof. Paulo Donato Castellane, 14884-900, Jaboticabal, Brazil
| | - Davi Rodrigo Rossatto
- Department of Biology Applied to Agriculture, São Paulo State University, Via de Acesso Prof. Paulo Donato Castellane, 14884-900, Jaboticabal, Brazil
| | - Isabel López-Díaz
- Institute for Plant Molecular and Cellular Biology (IBMCP), CSIC-UPV, Carrer de l'Enginyer Fausto Elio 46011, Valencia, Spain
| | - Esther Carrera
- Institute for Plant Molecular and Cellular Biology (IBMCP), CSIC-UPV, Carrer de l'Enginyer Fausto Elio 46011, Valencia, Spain
| | - Joni Esrom Lima
- Botany Department, Institute of Biological Sciences, Universidade Federal de Minas Gerais, Avenida Presidente Antônio Carlos, 6627, Minas Gerais, Brazil
| | | | - Rogério Falleiros Carvalho
- Department of Biology Applied to Agriculture, São Paulo State University, Via de Acesso Prof. Paulo Donato Castellane, 14884-900, Jaboticabal, Brazil.
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Carminati A, Passioura JB, Zarebanadkouki M, Ahmed MA, Ryan PR, Watt M, Delhaize E. Root hairs enable high transpiration rates in drying soils. THE NEW PHYTOLOGIST 2017; 216:771-781. [PMID: 28758687 DOI: 10.1111/nph.14715] [Citation(s) in RCA: 68] [Impact Index Per Article: 9.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2017] [Accepted: 06/21/2017] [Indexed: 05/24/2023]
Abstract
Do root hairs help roots take up water from the soil? Despite the well-documented role of root hairs in phosphate uptake, their role in water extraction is controversial. We grew barley (Hordeum vulgare cv Pallas) and its root-hairless mutant brb in a root pressure chamber, whereby the transpiration rate could be varied whilst monitoring the suction in the xylem. The method provides accurate measurements of the dynamic relationship between the transpiration rate and xylem suction. The relationship between the transpiration rate and xylem suction was linear in wet soils and did not differ between genotypes. When the soil dried, the xylem suction increased rapidly and non-linearly at high transpiration rates. This response was much greater with the brb mutant, implying a reduced capacity to take up water. We conclude that root hairs facilitate the uptake of water by substantially reducing the drop in matric potential at the interface between root and soil in rapidly transpiring plants. The experiments also reinforce earlier observations that there is a marked hysteresis in the suction in the xylem when the transpiration rate is rising compared with when it is falling, and possible reasons for this behavior are discussed.
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Affiliation(s)
- Andrea Carminati
- Chair of Soil Physics, University of Bayreuth, Bauyreuth, D-95447, Germany
| | - John B Passioura
- CSIRO Agriculture and Food, GPO Box 1600, Canberra, ACT, 2601, Australia
| | | | - Mutez A Ahmed
- Chair of Soil Physics, University of Bayreuth, Bauyreuth, D-95447, Germany
- Division of Soil Hydrology, Georg-August Universität, D-37073, Göttingen, Germany
- Department of Agricultural Engineering, Faculty of Agriculture, University of Khartoum, Khartoum North, 13314, Shambat, Sudan
| | - Peter R Ryan
- CSIRO Agriculture and Food, GPO Box 1600, Canberra, ACT, 2601, Australia
| | - Michelle Watt
- Plant Sciences, Institute of Bio- and Geosciences, Jülich Forschungszentrum, Jülich, D-52425, Germany
| | - Emmanuel Delhaize
- CSIRO Agriculture and Food, GPO Box 1600, Canberra, ACT, 2601, Australia
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Naveed M, Brown LK, Raffan AC, George TS, Bengough AG, Roose T, Sinclair I, Koebernick N, Cooper L, Hackett CA, Hallett PD. Plant exudates may stabilize or weaken soil depending on species, origin and time. EUROPEAN JOURNAL OF SOIL SCIENCE 2017; 68:806-816. [PMID: 29263712 PMCID: PMC5726377 DOI: 10.1111/ejss.12487] [Citation(s) in RCA: 49] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/25/2017] [Revised: 09/11/2017] [Accepted: 09/13/2017] [Indexed: 05/07/2023]
Abstract
We hypothesized that plant exudates could either gel or disperse soil depending on their chemical characteristics. Barley (Hordeum vulgare L. cv. Optic) and maize (Zea mays L. cv. Freya) root exudates were collected using an aerated hydroponic method and compared with chia (Salvia hispanica L.) seed exudate, a commonly used root exudate analogue. Sandy loam soil was passed through a 500-μm mesh and treated with each exudate at a concentration of 4.6 mg exudate g-1 dry soil. Two sets of soil samples were prepared. One set of treated soil samples was maintained at 4°C to suppress microbial processes. To characterize the effect of decomposition, the second set of samples was incubated at 16°C for 2 weeks at -30 kPa matric potential. Gas chromatography-mass spectrometry (GC-MS) analysis of the exudates showed that barley had the largest organic acid content and chia the largest content of sugars (polysaccharide-derived or free), and maize was in between barley and chia. Yield stress of amended soil samples was measured by an oscillatory strain sweep test with a cone plate rheometer. When microbial decomposition was suppressed at 4°C, yield stress increased 20-fold for chia seed exudate and twofold for maize root exudate compared with the control, whereas for barley root exudate decreased to half. The yield stress after 2 weeks of incubation compared with soil with suppressed microbial decomposition increased by 85% for barley root exudate, but for chia and maize it decreased by 87 and 54%, respectively. Barley root exudation might therefore disperse soil and this could facilitate nutrient release. The maize root and chia seed exudates gelled soil, which could create a more stable soil structure around roots or seeds. HIGHLIGHTS Rheological measurements quantified physical behaviour of plant exudates and effect on soil stabilization.Barley root exudates dispersed soil, which could release nutrients and carbon.Maize root and chia seed exudates had a stabilizing effect on soil.Physical engineering of soil in contact with plant roots depends on the nature and origin of exudates.
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Affiliation(s)
- M. Naveed
- School of Biological SciencesUniversity of AberdeenAberdeenAB24 3UUUK
| | - L. K. Brown
- The James Hutton Institute, InvergowrieDundeeDD2 5DAUK
| | - A. C. Raffan
- School of Biological SciencesUniversity of AberdeenAberdeenAB24 3UUUK
| | - T. S. George
- The James Hutton Institute, InvergowrieDundeeDD2 5DAUK
| | - A. G. Bengough
- The James Hutton Institute, InvergowrieDundeeDD2 5DAUK
- School of Science and EngineeringUniversity of DundeeDundeeDD1 4HNUK
| | - T. Roose
- Faculty of Engineering and EnvironmentUniversity of SouthamptonSouthamptonSO17 1BJUK
| | - I. Sinclair
- Faculty of Engineering and EnvironmentUniversity of SouthamptonSouthamptonSO17 1BJUK
| | - N. Koebernick
- School of Science and EngineeringUniversity of DundeeDundeeDD1 4HNUK
| | - L. Cooper
- School of Science and EngineeringUniversity of DundeeDundeeDD1 4HNUK
| | - C. A. Hackett
- Biomathematics and Statistics Scotland, InvergowrieDundeeDD2 5DAUK
| | - P. D. Hallett
- School of Biological SciencesUniversity of AberdeenAberdeenAB24 3UUUK
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Oleghe E, Naveed M, Baggs EM, Hallett PD. Plant exudates improve the mechanical conditions for root penetration through compacted soils. PLANT AND SOIL 2017; 421:19-30. [PMID: 31997836 PMCID: PMC6956916 DOI: 10.1007/s11104-017-3424-5] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/19/2017] [Accepted: 09/11/2017] [Indexed: 05/10/2023]
Abstract
BACKGROUND AND AIM Plant exudates greatly affect the physical behaviour of soil, but measurements of the impact of exudates on compression characteristics are missing. Our aim is to provide these data and explore how plant exudates may enhance the restructuring of compacted soils following cycles of wetting and drying. METHODS Two soils were amended with Chia (Salvia hispanica) seed exudate at 5 concentrations, compacted in cores to 200 kPa stress (equivalent to tractor stress), equilibrated to -50 kPa matric potential, and then compacted to 600 kPa (equivalent to axial root stress) followed by 3 cycles of wetting and drying and recompression to 600 kPa at -50 kPa matric potential. Penetration resistance (PR), compression index (CC) and pore characteristics were measured at various steps. RESULTS PR decreased and CC increased with increasing exudate concentration. At 600 kPa compression, 1.85 mg exudate g-1 soil increased CC from 0.37 to 0.43 for sandy loam soil and from 0.50 to 0.54 for clay loam soil. After 3 wetting-drying cycles the clay loam was more resillient than the sandy loam soil, with resilience increasing with greater exudate concentration. Root growth modelled on PR data suggested plant exudates significantly eased root elongation in soil. CONCLUSION Plant exudates improve compression characteristics of soils, easing penetration and enhancing recovery of root induced soil compaction.
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Affiliation(s)
- E. Oleghe
- School of Biological Sciences, University of Aberdeen, Cruickshank Building, Aberdeen, AB24 3UU UK
- Department of Soil Science, Ambrose Alli University, P.M.B 14, Ekpoma, Edo State Nigeria
| | - M. Naveed
- School of Biological Sciences, University of Aberdeen, Cruickshank Building, Aberdeen, AB24 3UU UK
| | - E. M. Baggs
- The Royal (Dick) School of Veterinary Studies, University of Edinburgh, Easter Bush Campus, Midlothian, EH25 9RG UK
| | - P. D. Hallett
- School of Biological Sciences, University of Aberdeen, Cruickshank Building, Aberdeen, AB24 3UU UK
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Schmidt JE, Gaudin ACM. Toward an Integrated Root Ideotype for Irrigated Systems. TRENDS IN PLANT SCIENCE 2017; 22:433-443. [PMID: 28262426 DOI: 10.1016/j.tplants.2017.02.001] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/21/2016] [Revised: 01/23/2017] [Accepted: 02/06/2017] [Indexed: 05/24/2023]
Abstract
Breeding towards root-centric ideotypes can be a relatively quick trait-based strategy to improve crop resource use efficiency. Irrigated agriculture represents a crucial and expanding sector, but its unique parameters require traits distinct from previously proposed rainfed ideotypes. We propose a novel irrigated ideotype that integrates traits across multiple scales to enhance resource use efficiency in irrigated agroecosystems, where resources are concentrated in a relatively shallow 'critical zone'. Unique components of this ideotype include rapid transplant recovery and establishment, enhanced exploitation of localized resource hotspots, adaptive physiological regulation, maintenance of hydraulic conductivity, beneficial rhizosphere interactions, and salinity/waterlogging avoidance. If augmented by future research, this target could help to enhance agricultural sustainability in irrigated agroecosystems by guiding the creation of resource-efficient cultivars.
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Affiliation(s)
- Jennifer E Schmidt
- Department of Plant Sciences, University of California (UC) Davis, Davis, CA 95616, USA
| | - Amélie C M Gaudin
- Department of Plant Sciences, University of California (UC) Davis, Davis, CA 95616, USA.
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Carminati A, Zarebanadkouki M, Kroener E, Ahmed MA, Holz M. Biophysical rhizosphere processes affecting root water uptake. ANNALS OF BOTANY 2016; 118:561-571. [PMID: 27345032 PMCID: PMC5055629 DOI: 10.1093/aob/mcw113] [Citation(s) in RCA: 27] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/29/2016] [Revised: 03/29/2016] [Accepted: 04/08/2016] [Indexed: 05/09/2023]
Abstract
Background Recent advances in imaging techniques now make it possible to visualize the biogeochemical and physical environment around the roots, the rhizosphere. Detailed images of pore space geometry and water content dynamics around roots have demonstrated the heterogeneity of the rhizosphere compared with the soil far from the roots. These findings have inspired new models of root water uptake which aim to describe such small-scale heterogeneity. However, the question remains of how far these image-based findings have really advanced our understanding of how roots extract water from soils. Scope The rhizosphere processes affecting root water uptake are reviewed. Special attention is dedicated to the role of mucilage exuded by roots. Mucilage increases the soil moisture at negative water potentials and it keeps the rhizosphere wet when plants take up water, possibly maintaining the hydraulic connection between roots and soil. However, mucilage becomes viscous and hydrophobic upon severe drying and it limits the water fluxes across the rhizosphere during the rewetting phase. The role of mucilage in maintaining the hydraulic contact between the root surface and the surrounding soil, thereby softening the drops in water potential around the roots in dry soils, remains to be demonstrated. Conclusion Despite detailed images of water content, water fluxes and soil structure in the rhizosphere, a general understanding of how the rhizosphere affects root water uptake is still lacking. The missing elements of the puzzle are the gradient in water potential around roots. Measurements of the xylem water potential at varying soil water potentials and transpiration rates supported by numerical models of root water uptake would allow the estimation of the water potential across the rhizosphere. Such measurements are crucial to comprehend how water enters the roots.
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Affiliation(s)
- A. Carminati
- Division of Soil Hydrology, Georg-August University, Göttingen, Germany
| | - M. Zarebanadkouki
- Division of Soil Hydrology, Georg-August University, Göttingen, Germany
| | - E. Kroener
- Division of Soil Hydrology, Georg-August University, Göttingen, Germany
| | - M. A. Ahmed
- Division of Soil Hydrology, Georg-August University, Göttingen, Germany
- Department of Agricultural Engineering, Faculty of Agriculture, University of Khartoum, Khartoum North, 13314 Shambat, Sudan
| | - M. Holz
- Division of Soil Hydrology, Georg-August University, Göttingen, Germany
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Kroener E, Ahmed MA, Carminati A. Roots at the percolation threshold. PHYSICAL REVIEW. E, STATISTICAL, NONLINEAR, AND SOFT MATTER PHYSICS 2015; 91:042706. [PMID: 25974526 DOI: 10.1103/physreve.91.042706] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/01/2014] [Indexed: 06/04/2023]
Abstract
The rhizosphere is the layer of soil around the roots where complex and dynamic interactions between plants and soil affect the capacity of plants to take up water. The physical properties of the rhizosphere are affected by mucilage, a gel exuded by roots. Mucilage can absorb large volumes of water, but it becomes hydrophobic after drying. We use a percolation model to describe the rewetting of dry rhizosphere. We find that at a critical mucilage concentration the rhizosphere becomes impermeable. The critical mucilage concentration depends on the radius of the soil particle size. Capillary rise experiments with neutron radiography prove that for concentrations below the critical mucilage concentration water could easily cross the rhizosphere, while above the critical concentration water could no longer percolate through it. Our studies, together with former observations of water dynamics in the rhizosphere, suggest that the rhizosphere is near the percolation threshold, where small variations in mucilage concentration sensitively alter the soil hydraulic conductivity. Is mucilage exudation a plant mechanism to efficiently control the rhizosphere conductivity and the access to water?
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Affiliation(s)
- Eva Kroener
- Division of Soil Hydrology, Department of Crop Science, University of Göttingen, Göttingen, Germany
| | - Mutez Ali Ahmed
- Division of Soil Hydrology, Department of Crop Science, University of Göttingen, Göttingen, Germany
| | - Andrea Carminati
- Division of Soil Hydrology, Department of Crop Science, University of Göttingen, Göttingen, Germany
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