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Reyer A, Bazihizina N, Jaślan J, Scherzer S, Schäfer N, Jaślan D, Becker D, Müller TD, Pommerrenig B, Neuhaus HE, Marten I, Hedrich R. Sugar beet PMT5a and STP13 carriers suitable for proton-driven plasma membrane sucrose and glucose import in taproots. Plant J 2024. [PMID: 38602250 DOI: 10.1111/tpj.16740] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 02/26/2024] [Accepted: 03/18/2024] [Indexed: 04/12/2024]
Abstract
Sugar beet (Beta vulgaris) is the major sugar-producing crop in Europe and Northern America, as the taproot stores sucrose at a concentration of around 20%. Genome sequence analysis together with biochemical and electrophysiological approaches led to the identification and characterization of the TST sucrose transporter driving vacuolar sugar accumulation in the taproot. However, the sugar transporters mediating sucrose uptake across the plasma membrane of taproot parenchyma cells remained unknown. As with glucose, sucrose stimulation of taproot parenchyma cells caused inward proton fluxes and plasma membrane depolarization, indicating a sugar/proton symport mechanism. To decipher the nature of the corresponding proton-driven sugar transporters, we performed taproot transcriptomic profiling and identified the cold-induced PMT5a and STP13 transporters. When expressed in Xenopus laevis oocytes, BvPMT5a was characterized as a voltage- and H+-driven low-affinity glucose transporter, which does not transport sucrose. In contrast, BvSTP13 operated as a high-affinity H+/sugar symporter, transporting glucose better than sucrose, and being more cold-tolerant than BvPMT5a. Modeling of the BvSTP13 structure with bound mono- and disaccharides suggests plasticity of the binding cleft to accommodate the different saccharides. The identification of BvPMT5a and BvSTP13 as taproot sugar transporters could improve breeding of sugar beet to provide a sustainable energy crop.
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Affiliation(s)
- Antonella Reyer
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Nadia Bazihizina
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Florence, 50019, Sesto Fiorentino, Italy
| | - Justyna Jaślan
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Sönke Scherzer
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Nadine Schäfer
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Dawid Jaślan
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
- Faculty of Medicine, Walther Straub Institute of Pharmacology and Toxicology, Ludwig Maximilians-Universität, 80336, Munich, Germany
| | - Dirk Becker
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Thomas D Müller
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Benjamin Pommerrenig
- Plant Physiology, University of Kaiserslautern, 67663, Kaiserslautern, Germany
- Julius Kühn Institute (JKI) - Federal Research Centre for Cultivated Plants, Institute for Resistance Research and Stress Tolerance, Quedlinburg, 06484, Germany
| | - H Ekkehard Neuhaus
- Plant Physiology, University of Kaiserslautern, 67663, Kaiserslautern, Germany
| | - Irene Marten
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
| | - Rainer Hedrich
- Department of Molecular Plant Physiology and Biophysics, Biocenter, Julius-Maximilians-Universität (JMU), Würzburg, 97082, Germany
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Dainelli M, Pignattelli S, Bazihizina N, Falsini S, Papini A, Baccelli I, Mancuso S, Coppi A, Castellani MB, Colzi I, Gonnelli C. Can microplastics threaten plant productivity and fruit quality? Insights from Micro-Tom and Micro-PET/PVC. Sci Total Environ 2023; 895:165119. [PMID: 37364840 DOI: 10.1016/j.scitotenv.2023.165119] [Citation(s) in RCA: 8] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/14/2023] [Revised: 06/20/2023] [Accepted: 06/23/2023] [Indexed: 06/28/2023]
Abstract
Solanum lycopersicum L., a crop grown worldwide with a high nutritional value for the human diet, was used to test the impact of microplastics on plant growth, productivity, and fruit quality. Two of the most represented microplastics in soils, polyethylene terephthalate (PET) and polyvinyl chloride (PVC), were tested. Plants were grown in pots with an environmentally realistic concentration of microplastics and, during the whole crop life cycle, photosynthetic parameters, number of flowers and fruits were monitored. At the end of the cultivation, plant biometry and ionome were evaluated, along with fruit production and quality. Both pollutants had negligible effects on shoot traits, with only PVC causing a significant reduction in shoot fresh weight. Despite an apparent low or no toxicity during the vegetative stage, both microplastics decreased the number of fruits and, in the case of PVC, also their fresh weights. The plastic polymer-induced decline in fruit production was coupled with wide variations in fruit ionome, with marked increases in Ni and Cd. By contrast there was a decline in the nutritionally valuable lycopene, total soluble solids, and total phenols. Altogether, our results reveal that microplastics can not only limit crop productivity but also negatively impact fruit quality and enhance the concentration of food safety hazards, thus raising concerns for their potential health risks for humans.
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Affiliation(s)
- Marco Dainelli
- Department of Biology, Università degli Studi di Firenze, via Micheli 1, 50121 Florence, Italy
| | - Sara Pignattelli
- CNR-Institute of Bioscience and Bioresources, via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy
| | - Nadia Bazihizina
- Department of Biology, Università degli Studi di Firenze, via Micheli 1, 50121 Florence, Italy
| | - Sara Falsini
- Department of Biology, Università degli Studi di Firenze, via Micheli 1, 50121 Florence, Italy
| | - Alessio Papini
- Department of Biology, Università degli Studi di Firenze, via Micheli 1, 50121 Florence, Italy
| | - Ivan Baccelli
- CNR-Institute for Sustainable Plant Protection, via Madonna del Piano 10, 50019 Sesto Fiorentino, Italy
| | - Stefano Mancuso
- Department of Agriculture, Food, Environment and Forestry, Università degli Studi di Firenze, via delle Idee 30, 50019 Sesto Fiorentino, Italy; Fondazione per il Futuro delle Città, Via Boccaccio 50, 50133 Firenze, Italy
| | - Andrea Coppi
- Department of Biology, Università degli Studi di Firenze, via Micheli 1, 50121 Florence, Italy
| | | | - Ilaria Colzi
- Department of Biology, Università degli Studi di Firenze, via Micheli 1, 50121 Florence, Italy
| | - Cristina Gonnelli
- Department of Biology, Università degli Studi di Firenze, via Micheli 1, 50121 Florence, Italy
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3
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Bazihizina N, Böhm J, Messerer M, Stigloher C, Müller HM, Cuin TA, Maierhofer T, Cabot J, Mayer KFX, Fella C, Huang S, Al-Rasheid KAS, Alquraishi S, Breadmore M, Mancuso S, Shabala S, Ache P, Zhang H, Zhu JK, Hedrich R, Scherzer S. Stalk cell polar ion transport provide for bladder-based salinity tolerance in Chenopodium quinoa. New Phytol 2022; 235:1822-1835. [PMID: 35510810 DOI: 10.1111/nph.18205] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 04/12/2022] [Indexed: 06/14/2023]
Abstract
Chenopodium quinoa uses epidermal bladder cells (EBCs) to sequester excess salt. Each EBC complex consists of a leaf epidermal cell, a stalk cell, and the bladder. Under salt stress, sodium (Na+ ), chloride (Cl- ), potassium (K+ ) and various metabolites are shuttled from the leaf lamina to the bladders. Stalk cells operate as both a selectivity filter and a flux controller. In line with the nature of a transfer cell, advanced transmission electron tomography, electrophysiology, and fluorescent tracer flux studies revealed the stalk cell's polar organization and bladder-directed solute flow. RNA sequencing and cluster analysis revealed the gene expression profiles of the stalk cells. Among the stalk cell enriched genes, ion channels and carriers as well as sugar transporters were most pronounced. Based on their electrophysiological fingerprint and thermodynamic considerations, a model for stalk cell transcellular transport was derived.
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Affiliation(s)
- Nadia Bazihizina
- Department of Agriculture, Food, Environment and Forestry (DAGRI), University of Florence, Viale delle Idee 30, 50019, Florence, Italy
- College of Science and Engineering, Tasmanian Institute for Agriculture, University of Tasmania, Private Bag 54, Hobart, Tas., 7001, Australia
| | - Jennifer Böhm
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082, Wuerzburg, Germany
| | - Maxim Messerer
- Plant Genome and Systems Biology, Helmholtz Center Munich, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Christian Stigloher
- Imaging Core Facility, Biocenter, University of Wuerzburg, Am Hubland, 97074, Wuerzburg, Germany
| | - Heike M Müller
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082, Wuerzburg, Germany
| | - Tracey Ann Cuin
- Biological Sciences, School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, Tas., 7001, Australia
| | - Tobias Maierhofer
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082, Wuerzburg, Germany
| | - Joan Cabot
- Diagnostic Devices Unit, LEITAT Technological Center, Innovació 2, Terrasse, 0822, Barcelona, Spain
| | - Klaus F X Mayer
- Plant Genome and Systems Biology, Helmholtz Center Munich, Ingolstädter Landstraße 1, 85764, Neuherberg, Germany
| | - Christian Fella
- Fraunhofer IIS, Nano CT Systeme, Josef-Martin-Weg 63, 97074, Wuerzburg, Germany
| | - Shouguang Huang
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082, Wuerzburg, Germany
| | - Khaled A S Al-Rasheid
- Zoology Department, College of Science, King Saud University, PO Box 2455, Riyadh, 11451, Saudi Arabia
| | - Saleh Alquraishi
- Zoology Department, College of Science, King Saud University, PO Box 2455, Riyadh, 11451, Saudi Arabia
| | - Michael Breadmore
- School of Natural Sciences, Australian Centre for Research on Separation Sciences (ACROSS), University of Tasmania, Private Bag 75, Hobart, Tas., 7001, Australia
| | - Stefano Mancuso
- Department of Agriculture, Food, Environment and Forestry (DAGRI), University of Florence, Viale delle Idee 30, 50019, Florence, Italy
| | - Sergey Shabala
- College of Science and Engineering, Tasmanian Institute for Agriculture, University of Tasmania, Private Bag 54, Hobart, Tas., 7001, Australia
- International Research Centre for Membrane Biology, Foshan University, Foshan, 528000, China
| | - Peter Ache
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082, Wuerzburg, Germany
| | - Heng Zhang
- State Key Laboratory of Plant Molecular Genetics, Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Jian-Kang Zhu
- State Key Laboratory of Plant Molecular Genetics, Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
- Institute of Advanced Biotechnology and School of Life Sciences, Southern University of Science and Technology, No. 1088, Xueyuan Avenue, Shenzhen, Nanshan District, China
| | - Rainer Hedrich
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082, Wuerzburg, Germany
| | - Sönke Scherzer
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082, Wuerzburg, Germany
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Valenzuela FJ, Reineke D, Leventini D, Chen CCL, Barrett-Lennard EG, Colmer TD, Dodd IC, Shabala S, Brown P, Bazihizina N. Plant responses to heterogeneous salinity: agronomic relevance and research priorities. Ann Bot 2022; 129:499-518. [PMID: 35171228 PMCID: PMC9007098 DOI: 10.1093/aob/mcac022] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2021] [Accepted: 02/14/2022] [Indexed: 06/12/2023]
Abstract
BACKGROUND Soil salinity, in both natural and managed environments, is highly heterogeneous, and understanding how plants respond to this spatiotemporal heterogeneity is increasingly important for sustainable agriculture in the era of global climate change. While the vast majority of research on crop response to salinity utilizes homogeneous saline conditions, a much smaller, but important, effort has been made in the past decade to understand plant molecular and physiological responses to heterogeneous salinity mainly by using split-root studies. These studies have begun to unravel how plants compensate for water/nutrient deprivation and limit salt stress by optimizing root-foraging in the most favourable parts of the soil. SCOPE This paper provides an overview of the patterns of salinity heterogeneity in rain-fed and irrigated systems. We then discuss results from split-root studies and the recent progress in understanding the physiological and molecular mechanisms regulating plant responses to heterogeneous root-zone salinity and nutrient conditions. We focus on mechanisms by which plants (salt/nutrient sensing, root-shoot signalling and water uptake) could optimize the use of less-saline patches within the root-zone, thereby enhancing growth under heterogeneous soil salinity conditions. Finally, we place these findings in the context of defining future research priorities, possible irrigation management and crop breeding opportunities to improve productivity from salt-affected lands.
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Affiliation(s)
| | - Daniela Reineke
- Department of Plant Sciences, University of California, Davis, CA, USA
| | - Dante Leventini
- Department of Plant Sciences, University of California, Davis, CA, USA
| | | | - Edward G Barrett-Lennard
- Land Management Group, Agriculture Discipline, College of Science, Health, Engineering and Education, Murdoch University, WA, Australia
- Department of Primary Industries and Regional Development, South Perth, WA, Australia
| | - Timothy D Colmer
- UWA School of Agriculture and Environment, The University of Western Australia, Crawley, WA, Australia
- Institute of Agriculture, The University of Western Australia, Crawley, WA, Australia
| | - Ian C Dodd
- The Lancaster Environment Centre, Lancaster University, Lancaster, UK
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan 528000, China
| | - Patrick Brown
- Department of Plant Sciences, University of California, Davis, CA, USA
| | - Nadia Bazihizina
- Department of Agriculture, Food, Environment and Forestry, University of Florence, Florence, Italy
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5
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Bazihizina N, Vita F, Balestrini R, Kiferle C, Caparrotta S, Ghignone S, Atzori G, Mancuso S, Shabala S. Early signalling processes in roots play a crucial role in the differential salt tolerance in contrasting Chenopodium quinoa accessions. J Exp Bot 2022; 73:292-306. [PMID: 34436573 DOI: 10.1093/jxb/erab388] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/09/2021] [Accepted: 08/23/2021] [Indexed: 06/13/2023]
Abstract
Significant variation in epidermal bladder cell (EBC) density and salt tolerance (ST) exists amongst quinoa accessions, suggesting that salt sequestration in EBCs is not the only mechanism conferring ST in this halophyte. In order to reveal other traits that may operate in tandem with salt sequestration in EBCs and whether these additional tolerance mechanisms acted mainly at the root or shoot level, two quinoa (Chenopodium quinoa) accessions with contrasting ST and EBC densities (Q30, low ST with high EBC density versus Q68, with high ST and low EBC density) were studied. The results indicate that responses in roots, rather than in shoots, contributed to the greater ST in the accession with low EBC density. In particular, the tolerant accession had improved root plasma membrane integrity and K+ retention in the mature root zone in response to salt. Furthermore, superior ST in the tolerant Q68 was associated with faster and root-specific H2O2 accumulation and reactive oxygen species-induced K+ and Ca2+ fluxes in the root apex within 30 min after NaCl application. This was found to be associated with the constitutive up-regulation of the membrane-localized receptor kinases regulatory protein FERONIA in the tolerant accession. Taken together, this study shows that differential root signalling events upon salt exposure are essential for the halophytic quinoa; the failure to do this limits quinoa adaptation to salinity, independently of salt sequestration in EBCs.
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Affiliation(s)
- Nadia Bazihizina
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Florence, Italy
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS, Australia
| | - Federico Vita
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Florence, Italy
| | - Raffaella Balestrini
- National Research Council, Institute for Sustainable Plant Protection, Turin, Italy
| | - Claudia Kiferle
- Plantlab, Institute of Life Sciences, Sant'Anna School of Advanced Studies, Pisa, Italy
| | - Stefania Caparrotta
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Florence, Italy
| | - Stefano Ghignone
- National Research Council, Institute for Sustainable Plant Protection, Turin, Italy
| | - Giulia Atzori
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Florence, Italy
| | - Stefano Mancuso
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Florence, Italy
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan, China
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6
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Vita F, Ghignone S, Bazihizina N, Rasouli F, Sabbatini L, Kiani-Pouya A, Kiferle C, Shabala S, Balestrini R, Mancuso S. Early responses to salt stress in quinoa genotypes with opposite behavior. Physiol Plant 2021; 173:1392-1420. [PMID: 33847396 DOI: 10.1111/ppl.13425] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2021] [Revised: 03/17/2021] [Accepted: 04/10/2021] [Indexed: 06/12/2023]
Abstract
Soil salinity is among the major abiotic stresses that plants must cope with, mainly in arid and semiarid regions. The tolerance to high salinity is an important agronomic trait to sustain food production. Quinoa is a halophytic annual pseudo-cereal species with high nutritional value that can secrete salt out of young leaves in external non-glandular cells called epidermal bladder cells (EBC). Previous work showed high salt tolerance, but low EBC density was associated with an improved response in the early phases of salinity stress, mediated by tissue-tolerance traits mainly in roots. We compared the transcript profiling of two quinoa genotypes with contrasting salt tolerance patterning to identify the candidate genes involved in the differentially early response among genotypes. The transcriptome profiling, supported by in vitro physiological analyses, provided insights into the early-stage molecular mechanisms, both at the shoot and root level, based on the sensitive/tolerance traits. Results showed the presence of numerous differentially expressed genes among genotypes, tissues, and treatments, with genes involved in hormonal and stress response upregulated mainly in the sensitive genotype, suggesting that tolerance may be correlated to restricted changes in gene expression, at least after a short salt stress. These data, showing constitutive differences between the two genotypes, represent a solid basis for further studies to characterize the salt tolerance traits. Additionally, new information provided by this work might be useful for the development of plant breeding or genome engineering programs in quinoa.
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Affiliation(s)
- Federico Vita
- Department of Agriculture, Food, Environment and Forestry (DAGRI), University of Florence, Florence, Italy
| | - Stefano Ghignone
- National Research Council of Italy, Institute for Sustainable Plant Protection (CNR-IPSP), Torino, Italy
| | - Nadia Bazihizina
- Department of Agriculture, Food, Environment and Forestry (DAGRI), University of Florence, Florence, Italy
| | - Fatemeh Rasouli
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Australia
| | - Leonardo Sabbatini
- Department of Agriculture, Food, Environment and Forestry (DAGRI), University of Florence, Florence, Italy
| | - Ali Kiani-Pouya
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Australia
| | - Claudia Kiferle
- Institute of Life Sciences, Scuola Superiore Sant'Anna, Pisa, Italy
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, College of Science and Engineering, University of Tasmania, Hobart, Australia
- International Research Centre for Environmental Membrane Biology, Foshan University, Foshan, China
| | - Raffaella Balestrini
- National Research Council of Italy, Institute for Sustainable Plant Protection (CNR-IPSP), Torino, Italy
| | - Stefano Mancuso
- Department of Agriculture, Food, Environment and Forestry (DAGRI), University of Florence, Florence, Italy
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7
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Bazihizina N, Colmer TD, Cuin TA, Mancuso S, Shabala S. Friend or Foe? Chloride Patterning in Halophytes. Trends Plant Sci 2019; 24:142-151. [PMID: 30558965 DOI: 10.1016/j.tplants.2018.11.003] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/05/2018] [Revised: 11/11/2018] [Accepted: 11/16/2018] [Indexed: 06/09/2023]
Abstract
In this opinion article, we challenge the traditional view that breeding for reduced Cl- uptake would benefit plant salinity tolerance. A negative correlation between shoot Cl- concentration and plant biomass does not hold for halophytes - naturally salt tolerant species. We argue that, under physiologically relevant conditions, Cl- uptake requires plants to invest metabolic energy, and that the poor selectivity of Cl--transporting proteins may explain the reported negative correlation between Cl- accumulation and crop salinity tolerance. We propose a new paradigm: salinity tolerance could be achieved by improving the selectivity of some of the broadly selective anion-transporting proteins (e.g., for NO3->Cl-), alongside tight control of Cl- uptake, rather than targeting traits mediating its efflux from the root.
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Affiliation(s)
- Nadia Bazihizina
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy; Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia.
| | - Timothy D Colmer
- UWA School of Agriculture and Environment, Faculty of Science, University of Western Australia (UWA), 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Tracey Ann Cuin
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia
| | - Stefano Mancuso
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy
| | - Sergey Shabala
- Tasmanian Institute of Agriculture, University of Tasmania, Hobart, TAS 7001, Australia.
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8
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Böhm J, Messerer M, Müller HM, Scholz-Starke J, Gradogna A, Scherzer S, Maierhofer T, Bazihizina N, Zhang H, Stigloher C, Ache P, Al-Rasheid KAS, Mayer KFX, Shabala S, Carpaneto A, Haberer G, Zhu JK, Hedrich R. Understanding the Molecular Basis of Salt Sequestration in Epidermal Bladder Cells of Chenopodium quinoa. Curr Biol 2018; 28:3075-3085.e7. [PMID: 30245105 DOI: 10.1016/j.cub.2018.08.004] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2018] [Revised: 06/20/2018] [Accepted: 08/01/2018] [Indexed: 02/03/2023]
Abstract
Soil salinity is destroying arable land and is considered to be one of the major threats to global food security in the 21st century. Therefore, the ability of naturally salt-tolerant halophyte plants to sequester large quantities of salt in external structures, such as epidermal bladder cells (EBCs), is of great interest. Using Chenopodium quinoa, a pseudo-cereal halophyte of great economic potential, we have shown previously that, upon removal of salt bladders, quinoa becomes salt sensitive. In this work, we analyzed the molecular mechanism underlying the unique salt dumping capabilities of bladder cells in quinoa. The transporters differentially expressed in the EBC transcriptome and functional electrophysiological testing of key EBC transporters in Xenopus oocytes revealed that loading of Na+ and Cl- into EBCs is mediated by a set of tailored plasma and vacuole membrane-based sodium-selective channel and chloride-permeable transporter.
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Affiliation(s)
- Jennifer Böhm
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Private Bag 54, Hobart, TAS 7001, Australia
| | - Maxim Messerer
- Plant Genome and Systems Biology, Helmholtz Center Munich, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Heike M Müller
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082 Wuerzburg, Germany
| | - Joachim Scholz-Starke
- Institute of Biophysics, National Research Council (CNR), Via De Marini 6, 16149 Genova, Italy
| | - Antonella Gradogna
- Institute of Biophysics, National Research Council (CNR), Via De Marini 6, 16149 Genova, Italy
| | - Sönke Scherzer
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082 Wuerzburg, Germany
| | - Tobias Maierhofer
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082 Wuerzburg, Germany
| | - Nadia Bazihizina
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Private Bag 54, Hobart, TAS 7001, Australia; Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy
| | - Heng Zhang
- Shanghai Center for Plant Stress Biology, and CAS Center for Excellence in Molecular Plant Sciences, 3888 Chenhua Road, Shanghai 201602, China
| | - Christian Stigloher
- Imaging Core Facility, Biocenter, University of Wuerzburg, Am Hubland, 97074 Wuerzburg, Germany
| | - Peter Ache
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082 Wuerzburg, Germany
| | - Khaled A S Al-Rasheid
- Zoology Department, College of Science, King Saud University, PO Box 2455, Riyadh 11451, Saudi Arabia
| | - Klaus F X Mayer
- Plant Genome and Systems Biology, Helmholtz Center Munich, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany
| | - Sergey Shabala
- Tasmanian Institute for Agriculture, College of Science and Engineering, University of Tasmania, Private Bag 54, Hobart, TAS 7001, Australia; Department of Horticulture, Foshan University, Foshan 528000, PRC
| | - Armando Carpaneto
- Institute of Biophysics, National Research Council (CNR), Via De Marini 6, 16149 Genova, Italy; Department of Earth, Environment and Life Sciences (DISTAV), University of Genoa, Viale Benedetto XV 5, 16132 Genova, Italy
| | - Georg Haberer
- Plant Genome and Systems Biology, Helmholtz Center Munich, Ingolstädter Landstraße 1, 85764 Neuherberg, Germany.
| | - Jian-Kang Zhu
- Shanghai Center for Plant Stress Biology, and CAS Center for Excellence in Molecular Plant Sciences, 3888 Chenhua Road, Shanghai 201602, China; Department of Horticulture and Landscape Architecture, Purdue University, 625 Agriculture Mall Drive, West Lafayette, IN 47907, USA.
| | - Rainer Hedrich
- Institute for Molecular Plant Physiology and Biophysics, University of Wuerzburg, Julius-von-Sachs Platz 2, 97082 Wuerzburg, Germany.
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9
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Wu H, Shabala L, Azzarello E, Huang Y, Pandolfi C, Su N, Wu Q, Cai S, Bazihizina N, Wang L, Zhou M, Mancuso S, Chen Z, Shabala S. Na+ extrusion from the cytosol and tissue-specific Na+ sequestration in roots confer differential salt stress tolerance between durum and bread wheat. J Exp Bot 2018; 69:3987-4001. [PMID: 29897491 PMCID: PMC6054258 DOI: 10.1093/jxb/ery194] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2017] [Accepted: 05/21/2018] [Indexed: 05/25/2023]
Abstract
The progress in plant breeding for salinity stress tolerance is handicapped by the lack of understanding of the specificity of salt stress signalling and adaptation at the cellular and tissue levels. In this study, we used electrophysiological, fluorescence imaging, and real-time quantitative PCR tools to elucidate the essentiality of the cytosolic Na+ extrusion in functionally different root zones (elongation, meristem, and mature) in a large number of bread and durum wheat accessions. We show that the difference in the root's ability for vacuolar Na+ sequestration in the mature zone may explain differential salinity stress tolerance between salt-sensitive durum and salt-tolerant bread wheat species. Bread wheat genotypes also had on average 30% higher capacity for net Na+ efflux from the root elongation zone, providing the first direct evidence for the essentiality of the root salt exclusion trait at the cellular level. At the same time, cytosolic Na+ accumulation in the root meristem was significantly higher in bread wheat, leading to the suggestion that this tissue may harbour a putative salt sensor. This hypothesis was then tested by investigating patterns of Na+ distribution and the relative expression level of several key genes related to Na+ transport in leaves in plants with intact roots and in those in which the root meristems were removed. We show that tampering with this sensing mechanism has resulted in a salt-sensitive phenotype, largely due to compromising the plant's ability to sequester Na+ in mesophyll cell vacuoles. The implications of these findings for plant breeding for salinity stress tolerance are discussed.
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Affiliation(s)
- Honghong Wu
- School of Land and Food, University of Tasmania, Private Bag, Hobart, Tasmania, Australia
| | - Lana Shabala
- School of Land and Food, University of Tasmania, Private Bag, Hobart, Tasmania, Australia
| | - Elisa Azzarello
- Department of Horticulture, University of Florence, Sesto Fiorentino, Italy
| | - Yuqing Huang
- School of Science and Health, Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Camilla Pandolfi
- Department of Horticulture, University of Florence, Sesto Fiorentino, Italy
| | - Nana Su
- School of Land and Food, University of Tasmania, Private Bag, Hobart, Tasmania, Australia
| | - Qi Wu
- School of Land and Food, University of Tasmania, Private Bag, Hobart, Tasmania, Australia
| | - Shengguan Cai
- School of Science and Health, Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Nadia Bazihizina
- School of Land and Food, University of Tasmania, Private Bag, Hobart, Tasmania, Australia
- Department of Horticulture, University of Florence, Sesto Fiorentino, Italy
| | - Lu Wang
- School of Natural Sciences, University of Tasmania, Private Bag 55, Hobart, Tasmania, Australia
| | - Meixue Zhou
- School of Land and Food, University of Tasmania, Private Bag, Hobart, Tasmania, Australia
| | - Stefano Mancuso
- Department of Horticulture, University of Florence, Sesto Fiorentino, Italy
| | - Zhonghua Chen
- School of Science and Health, Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, Private Bag, Hobart, Tasmania, Australia
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10
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Rodrigo-Moreno A, Bazihizina N, Azzarello E, Masi E, Tran D, Bouteau F, Baluska F, Mancuso S. Root phonotropism: Early signalling events following sound perception in Arabidopsis roots. Plant Sci 2017; 264:9-15. [PMID: 28969806 DOI: 10.1016/j.plantsci.2017.08.001] [Citation(s) in RCA: 26] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/20/2017] [Revised: 07/31/2017] [Accepted: 08/01/2017] [Indexed: 05/10/2023]
Abstract
Sound is a fundamental form of energy and it has been suggested that plants can make use of acoustic cues to obtain information regarding their environments and alter and fine-tune their growth and development. Despite an increasing body of evidence indicating that it can influence plant growth and physiology, many questions concerning the effect of sound waves on plant growth and the underlying signalling mechanisms remains unknown. Here we show that in Arabidopsis thaliana, exposure to sound waves (200Hz) for 2 weeks induced positive phonotropism in roots, which grew towards to sound source. We found that sound waves triggered very quickly (within minutes) an increase in cytosolic Ca2+, possibly mediated by an influx through plasma membrane and a release from internal stock. Sound waves likewise elicited rapid reactive oxygen species (ROS) production and K+ efflux. Taken together these results suggest that changes in ion fluxes (Ca2+ and K+) and an increase in superoxide production are involved in sound perception in plants, as previously established in animals.
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Affiliation(s)
- Ana Rodrigo-Moreno
- Department of Agrifood Production and Environmental Sciences - Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy.
| | - Nadia Bazihizina
- Department of Agrifood Production and Environmental Sciences - Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy
| | - Elisa Azzarello
- Department of Agrifood Production and Environmental Sciences - Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy
| | - Elisa Masi
- Department of Agrifood Production and Environmental Sciences - Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy
| | - Daniel Tran
- Université Paris Diderot, Sorbonne Paris Cité, Laboratoire Interdisciplinaire des Energies de Demain, Paris, France
| | - François Bouteau
- Université Paris Diderot, Sorbonne Paris Cité, Laboratoire Interdisciplinaire des Energies de Demain, Paris, France
| | | | - Stefano Mancuso
- Department of Agrifood Production and Environmental Sciences - Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy
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11
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Bazihizina N, Veneklaas EJ, Barrett-Lennard EG, Colmer TD. Hydraulic redistribution: limitations for plants in saline soils. Plant Cell Environ 2017; 40:2437-2446. [PMID: 28707352 DOI: 10.1111/pce.13020] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/10/2017] [Accepted: 06/25/2017] [Indexed: 06/07/2023]
Abstract
Hydraulic redistribution (HR), the movement of water from wet to dry patches in the soil via roots, occurs in different ecosystems and plant species. By extension of the principle that HR is driven by gradients in soil water potential, HR has been proposed to occur for plants in saline soils. Despite the inherent spatial patchiness and salinity gradients in these soils, the lack of direct evidence of HR in response to osmotic gradients prompted us to ask the question: are there physical or physiological constraints to HR for plants in saline environments? We propose that build-up of ions in the root xylem sap and in the leaf apoplast, with the latter resulting in a large predawn disequilibrium of water potential in shoots compared with roots and soil, would both impede HR. We present a conceptual model that illustrates how processes in root systems in heterogeneous salinity with water potential gradients, even if equal to those in non-saline soils, will experience a dampened magnitude of water potential gradients in the soil-plant continuum, minimizing or preventing HR. Finally, we provide an outlook for understanding the relevance of HR for plants in saline environments by addressing key research questions on plant salinity tolerance.
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Affiliation(s)
- Nadia Bazihizina
- Department of Agrifood Production and Environmental Sciences, Università degli Studi di Firenze, Viale delle Idee 30, 50019 Sesto Fiorentino, Florence, Italy
- School of Land and Food, University of Tasmania, Hobart, TAS, 7001, Australia
- UWA School of Agriculture and Environment, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Erik J Veneklaas
- UWA School of Agriculture and Environment, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
- School of Biological Sciences, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
- The UWA Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Edward G Barrett-Lennard
- UWA School of Agriculture and Environment, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
- Department of Agriculture and Food, Western Australia, 3 Baron-Hay Court, South, Perth, Western Australia, 6151, Australia
- School of Veterinary and Life Science, Murdoch University, 90 South Street, Murdoch, Western Australia, 6150, Australia
| | - Timothy D Colmer
- UWA School of Agriculture and Environment, Faculty of Science, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
- The UWA Institute of Agriculture, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
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12
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Kiani-Pouya A, Roessner U, Jayasinghe NS, Lutz A, Rupasinghe T, Bazihizina N, Bohm J, Alharbi S, Hedrich R, Shabala S. Epidermal bladder cells confer salinity stress tolerance in the halophyte quinoa and Atriplex species. Plant Cell Environ 2017; 40:1900-1915. [PMID: 28558173 DOI: 10.1111/pce.12995] [Citation(s) in RCA: 60] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Accepted: 05/21/2017] [Indexed: 05/02/2023]
Abstract
Epidermal bladder cells (EBCs) have been postulated to assist halophytes in coping with saline environments. However, little direct supporting evidence is available. Here, Chenopodium quinoa plants were grown under saline conditions for 5 weeks. One day prior to salinity treatment, EBCs from all leaves and petioles were gently removed by using a soft cosmetic brush and physiological, ionic and metabolic changes in brushed and non-brushed leaves were compared. Gentle removal of EBC neither initiated wound metabolism nor affected the physiology and biochemistry of control-grown plants but did have a pronounced effect on salt-grown plants, resulting in a salt-sensitive phenotype. Of 91 detected metabolites, more than half were significantly affected by salinity. Removal of EBC dramatically modified these metabolic changes, with the biggest differences reported for gamma-aminobutyric acid (GABA), proline, sucrose and inositol, affecting ion transport across cellular membranes (as shown in electrophysiological experiments). This work provides the first direct evidence for a role of EBC in salt tolerance in halophytes and attributes this to (1) a key role of EBC as a salt dump for external sequestration of sodium; (2) improved K+ retention in leaf mesophyll and (3) EBC as a storage space for several metabolites known to modulate plant ionic relations.
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Affiliation(s)
- Ali Kiani-Pouya
- School of Land and Food, University of Tasmania, 7001, Hobart, Tasmania, Australia
| | - Ute Roessner
- School of BioSciences, The University of Melbourne, 3010, Parkville, Victoria, Australia
- Metabolomics Australia, School of BioSciences, The University of Melbourne, 3010, Parkville, Victoria, Australia
| | - Nirupama S Jayasinghe
- Metabolomics Australia, School of BioSciences, The University of Melbourne, 3010, Parkville, Victoria, Australia
| | - Adrian Lutz
- Metabolomics Australia, School of BioSciences, The University of Melbourne, 3010, Parkville, Victoria, Australia
| | - Thusitha Rupasinghe
- Metabolomics Australia, School of BioSciences, The University of Melbourne, 3010, Parkville, Victoria, Australia
| | - Nadia Bazihizina
- School of Land and Food, University of Tasmania, 7001, Hobart, Tasmania, Australia
- Deptartment of Agrifood Production and Environmental Science, University of Florence, I-50019, Florence, Italy
| | - Jennifer Bohm
- School of Land and Food, University of Tasmania, 7001, Hobart, Tasmania, Australia
- Institute for Molecular Plant Physiology and Biophysics, Biocenter, Würzburg University, 97082, Wurzburg, Germany
| | - Sulaiman Alharbi
- Zoology Department, College of Science, King Saud University, P.O. Box 2455, Riyadh, 11451, Saudi Arabia
| | - Rainer Hedrich
- Institute for Molecular Plant Physiology and Biophysics, Biocenter, Würzburg University, 97082, Wurzburg, Germany
| | - Sergey Shabala
- School of Land and Food, University of Tasmania, 7001, Hobart, Tasmania, Australia
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13
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Marone E, Masi E, Taiti C, Pandolfi C, Bazihizina N, Azzarello E, Fiorino P, Mancuso S. Sensory, spectrometric (PTR-ToF-MS) and chemometric analyses to distinguish extra virgin from virgin olive oils. J Food Sci Technol 2017; 54:1368-1376. [PMID: 28559595 DOI: 10.1007/s13197-017-2541-8] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Revised: 10/13/2016] [Accepted: 02/08/2017] [Indexed: 11/30/2022]
Abstract
Olive oil samples were obtained from six cultivars grown in different environments, and graded by chemical analyses as extra virgin (EVOOs). These were evaluated for flavors and off-flavors, and relative VOCs spectrum as determined by PTR-ToF-MS. A hierarchical clustering of Panel test data separated olive oil in three groups, one including the samples with perceived off-flavor (VOOs), regardless of cultivar and environment. The Pearson's correlation coefficients between the mass data from PTR-ToF-MS and the sensory characteristics perceived by the Panel test were determined. A mass-to-sensory attributes correlation index was calculated. A color-coded card was built up based on the intensities (ncps) of five selected protonated mass data that was able to distinguish EVOOs from VOOs olive oil samples.
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Affiliation(s)
- Elettra Marone
- Faculty of Biosciences and Technologies for Agriculture Food and Environment, University of Teramo, Via R. Balzarini, 1, 64100 Teramo, Italy
| | - Elisa Masi
- Department of Agrifood Production and Environmental Science, University of Florence, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence Italy
| | - Cosimo Taiti
- Department of Agrifood Production and Environmental Science, University of Florence, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence Italy
| | - Camilla Pandolfi
- Department of Agrifood Production and Environmental Science, University of Florence, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence Italy
| | - Nadia Bazihizina
- Department of Agrifood Production and Environmental Science, University of Florence, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence Italy
| | - Elisa Azzarello
- Department of Agrifood Production and Environmental Science, University of Florence, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence Italy
| | - Piero Fiorino
- Department of Agrifood Production and Environmental Science, University of Florence, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence Italy
| | - Stefano Mancuso
- Department of Agrifood Production and Environmental Science, University of Florence, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence Italy
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14
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Pandolfi C, Bazihizina N, Giordano C, Mancuso S, Azzarello E. Salt acclimation process: a comparison between a sensitive and a tolerant Olea europaea cultivar. Tree Physiol 2017; 37:380-388. [PMID: 28338715 DOI: 10.1093/treephys/tpw127] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2016] [Accepted: 12/04/2016] [Indexed: 06/06/2023]
Abstract
Saline soils are highly heterogeneous in time and space, and this is a critical factor influencing plant physiology and productivity. Temporal changes in soil salinity can alter plant responses to salinity, and pre-treating plants with low NaCl concentrations has been found to substantially increase salt tolerance in different species in a process called acclimation. However, it still remains unclear whether this process is common to all plants or is only expressed in certain genotypes. We addressed this question by assessing the physiological changes to 100 mM NaCl in two contrasting olive cultivars (the salt-sensitive Leccino and the salt-tolerant Frantoio), following a 1-month acclimation period with 5 or 25 mM NaCl. The acclimation improved salt tolerance in both cultivars, but activated substantially different physiological adjustments in the tolerant and the sensitive cultivars. In the tolerant Frantoio the acclimation with 5 mM NaCl was more effective in increasing plant salt tolerance, with a 47% increase in total plant dry mass compared with non-acclimated saline plants. This enhanced biomass accumulation was associated with a 50% increase in K+ retention ability in roots. On the other hand, in the sensitive Leccino, although the acclimation process did not improve performance in terms of plant growth, pre-treatment with 5 and 25 mM NaCl substantially decreased salt-induced leaf cell ultrastructural changes, with leaf cell relatively similar to those of control plants. Taken together these results suggest that in the tolerant cultivar the acclimation took place primarily in the root tissues, while in the sensitive they occurred mainly at the shoot level.
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Affiliation(s)
- Camilla Pandolfi
- University of Florence, Department of Agrifood production and Environmental Sciences, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence, Italy
| | - Nadia Bazihizina
- University of Florence, Department of Agrifood production and Environmental Sciences, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence, Italy
| | - Cristiana Giordano
- Centro di Microscopie Elettroniche "Laura Bonzi", ICCOM, Consiglio Nazionale delle Ricerche (CNR), Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Florence, Italy
- Tree and Timber Institute, IVALSA, CNR, Via Madonna del Piano, 10, 50019 Sesto Fiorentino, Florence, Italy
| | - Stefano Mancuso
- University of Florence, Department of Agrifood production and Environmental Sciences, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence, Italy
| | - Elisa Azzarello
- University of Florence, Department of Agrifood production and Environmental Sciences, Viale delle Idee, 30, 50019 Sesto Fiorentino, Florence, Italy
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15
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Luti S, Caselli A, Taiti C, Bazihizina N, Gonnelli C, Mancuso S, Pazzagli L. PAMP Activity of Cerato-Platanin during Plant Interaction: An -Omic Approach. Int J Mol Sci 2016; 17:ijms17060866. [PMID: 27271595 PMCID: PMC4926400 DOI: 10.3390/ijms17060866] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2016] [Revised: 05/12/2016] [Accepted: 05/21/2016] [Indexed: 12/25/2022] Open
Abstract
Cerato-platanin (CP) is the founder of a fungal protein family consisting in non-catalytic secreted proteins, which work as virulence factors and/or as elicitors of defense responses and systemic resistance, thus acting as PAMPs (pathogen-associated molecular patterns). Moreover, CP has been defined an expansin-like protein showing the ability to weaken cellulose aggregates, like the canonical plant expansins do. Here, we deepen the knowledge on CP PAMP activity by the use of a multi-disciplinary approach: proteomic analysis, VOC (volatile organic compound) measurements, and gas exchange determination. The treatment of Arabidopsis with CP induces a differential profile either in protein expression or in VOC emission, as well changes in photosynthetic activity. In agreement with its role of defense activator, CP treatment induces down-expression of enzymes related to primary metabolism, such as RuBisCO, triosephosphate isomerase, and ATP-synthase, and reduces the photosynthesis rate. Conversely, CP increases expression of defense-related proteins and emission of some VOCs. Interestingly, CP exposure triggered the increase in enzymes involved in GSH metabolism and redox homeostasis (glutathione S-transferase, thioredoxin, Cys-peroxiredoxin, catalase) and in enzymes related to the “glucosinolate-myrosinase” system, which are the premise for synthesis of defence compounds, such as camalexin and some VOCs, respectively. The presented results are in agreement with the accepted role of CP as a PAMP and greatly increase the knowledge of plant primary defences induced by a purified fungal elicitor.
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Affiliation(s)
- Simone Luti
- Department of Biomedical Experimental and Clinical Sciences, Università di Firenze, viale Morgagni 50, 50134 Firenze, Italy.
| | - Anna Caselli
- Department of Biomedical Experimental and Clinical Sciences, Università di Firenze, viale Morgagni 50, 50134 Firenze, Italy.
| | - Cosimo Taiti
- Department of Agri-Food and Environmental Science, Università di Firenze, via delle Idee 30, 50019 Sesto Fiorentino, Italy.
| | - Nadia Bazihizina
- Department of Agri-Food and Environmental Science, Università di Firenze, via delle Idee 30, 50019 Sesto Fiorentino, Italy.
| | - Cristina Gonnelli
- Department of Biology, Università di Firenze, via Micheli 1, 50121 Firenze, Italy.
| | - Stefano Mancuso
- Department of Agri-Food and Environmental Science, Università di Firenze, via delle Idee 30, 50019 Sesto Fiorentino, Italy.
| | - Luigia Pazzagli
- Department of Biomedical Experimental and Clinical Sciences, Università di Firenze, viale Morgagni 50, 50134 Firenze, Italy.
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16
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Taiti C, Giorni E, Colzi I, Pignattelli S, Bazihizina N, Buccianti A, Luti S, Pazzagli L, Mancuso S, Gonnelli C. Under fungal attack on a metalliferous soil: ROS or not ROS? Insights from Silene paradoxa L. growing under copper stress. Environ Pollut 2016; 210:282-292. [PMID: 26799504 DOI: 10.1016/j.envpol.2015.12.020] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/24/2015] [Revised: 12/09/2015] [Accepted: 12/09/2015] [Indexed: 06/05/2023]
Abstract
We investigated how the adaptation to metalliferous environments can influence the plant response to biotic stress. In a metallicolous and a non-metallicolous population of Silene paradoxa the induction of oxidative stress and the production of callose and volatiles were evaluated in the presence of copper and of the PAMP fungal protein cerato-platanin, separately and in combination. Our results showed incompatibility between the ordinary ROS-mediated response to fungal attack and the acquired mechanisms of preventing oxidative stress in the tolerant population. A similar situation was also demonstrated by the sensitive population growing in the presence of copper but, in this case, with a lack of certain responses, such as callose production. In addition, in terms of the joint behaviour of emitted volatiles, multivariate statistics showed that not only did the populations respond differently to the presence of copper or biotic stress, but also that the biotic and abiotic stresses interacted in different ways in the two populations. Our results demonstrated that the same incompatibility of hyperaccumulators in ROS-mediated biotic stress signals also seemed to be exhibited by the excluder metallophyte, but without the advantage of being able to rely on the elemental defence for plant protection from natural enemies.
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Affiliation(s)
- Cosimo Taiti
- Department of Agri-Food and Environmental Science, Università di Firenze, via delle Idee 30, 50019, Sesto Fiorentino, Italy.
| | - Elisabetta Giorni
- Department of Biology, Università di Firenze, via Micheli 1, 50121, Firenze, Italy.
| | - Ilaria Colzi
- Department of Biology, Università di Firenze, via Micheli 1, 50121, Firenze, Italy.
| | - Sara Pignattelli
- Department of Biology, Università di Firenze, via Micheli 1, 50121, Firenze, Italy.
| | - Nadia Bazihizina
- Department of Agri-Food and Environmental Science, Università di Firenze, via delle Idee 30, 50019, Sesto Fiorentino, Italy.
| | - Antonella Buccianti
- Department of Earth Science, Università di Firenze, via La Pira 4, 50121, Firenze, Italy.
| | - Simone Luti
- Department of Biomedical Experimental and Clinical Sciences, Università di Firenze, viale Morgagni 50, 50134, Firenze, Italy.
| | - Luigia Pazzagli
- Department of Biomedical Experimental and Clinical Sciences, Università di Firenze, viale Morgagni 50, 50134, Firenze, Italy.
| | - Stefano Mancuso
- Department of Agri-Food and Environmental Science, Università di Firenze, via delle Idee 30, 50019, Sesto Fiorentino, Italy.
| | - Cristina Gonnelli
- Department of Biology, Università di Firenze, via Micheli 1, 50121, Firenze, Italy.
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17
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Taiti C, Costa C, Menesatti P, Comparini D, Bazihizina N, Azzarello E, Masi E, Mancuso S. Class-modeling approach to PTR-TOFMS data: a peppers case study. J Sci Food Agric 2015; 95:1757-1763. [PMID: 24871623 DOI: 10.1002/jsfa.6761] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/06/2014] [Revised: 05/09/2014] [Accepted: 05/22/2014] [Indexed: 06/03/2023]
Abstract
BACKGROUND Proton transfer reaction-mass spectrometry (PTR-MS), in its recently developed implementation based on time-of-flight mass spectrometry (PTR-TOFMS), was used to rapidly determine the volatile compounds present in fruits of Capsicum spp. RESULTS We analyzed the volatile organic compounds emission profile of freshly cut chili peppers belonging to three species and 33 different cultivars. PTR-TOFMS data, analyzed with appropriate and advanced multivariate class-modeling approaches, perfectly discriminated among the three species (100% correct classification in validation set). VIP (variable importance in projection) scores were used to select the 15 most important volatile compounds in discriminating the species. The best candidates for Capsicum spp. were compounds with measured m/z of 63.027, 101.096 and 107.050, which were, respectively, tentatively identified as dimethyl sulfide, hexanal and benzaldehyde. CONCLUSIONS Based on the promising results, the possibility of introducing multivariate class-modeling techniques, different from the classification approaches, in the field of volatile compounds analyses is discussed.
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Affiliation(s)
- Cosimo Taiti
- Università degli Studi di Firenze, Dipartimento di Scienze delle Produzioni Agroalimentari e dell'Ambiente, 50019, Sesto Fiorentino (FI), Italy
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Bazihizina N, Colzi I, Giorni E, Mancuso S, Gonnelli C. Photosynthesizing on metal excess: copper differently induced changes in various photosynthetic parameters in copper tolerant and sensitive Silene paradoxa L. populations. Plant Sci 2015; 232:67-76. [PMID: 25617325 DOI: 10.1016/j.plantsci.2014.12.015] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2014] [Revised: 12/16/2014] [Accepted: 12/17/2014] [Indexed: 05/22/2023]
Abstract
This work investigated Cu-induced changes in photosynthetic activity in contrasting populations of Silene paradoxa L. A metallicolous Cu-tolerant population and a non-metallicolous sensitive population were grown in hydroponics and exposed to different CuSO4 treatments for different times. Copper accumulation, MDA concentrations, and several photosynthetic parameters were measured to assess different effects of Cu exposure on plants from the two populations. A more efficient ability to photosynthesize in the presence of Cu excess was showed by the Cu-tolerant population with respect to the sensitive one. Interestingly, Cu-imposed limitations were present not only at a different degree, but also of different nature in the two populations. In the tolerant population, the most limiting factor to photosynthesis seemed to be Cu-imposed stomatal closure, whereas Cu-mediated biochemical limitation was scarce and Cu-mediated reduction in mesophyll conductance almost non-existent. In the sensitive population, Cu largely affected all the measured parameters, so that its photosynthetic activity experienced any kind of limitation, diffusional and especially biochemical. The lower Cu concentrations accumulated in the tolerant plant could be one of the factors concurring to the reported differences in photosynthetic activity, but also a higher capacity of internal detoxification and compartmentalization of the metal could not be excluded.
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Affiliation(s)
- Nadia Bazihizina
- Department of Agri-Food and Environmental Science, Università di Firenze, via delle Idee 30, Sesto Fiorentino, 50019 Firenze, Italy.
| | - Ilaria Colzi
- Department of Biology, Università di Firenze, via Micheli 1, 50121 Firenze, Italy.
| | - Elisabetta Giorni
- Department of Biology, Università di Firenze, via Micheli 1, 50121 Firenze, Italy.
| | - Stefano Mancuso
- Department of Agri-Food and Environmental Science, Università di Firenze, via delle Idee 30, Sesto Fiorentino, 50019 Firenze, Italy.
| | - Cristina Gonnelli
- Department of Biology, Università di Firenze, via Micheli 1, 50121 Firenze, Italy.
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Taiti C, Costa C, Menesatti P, Caparrotta S, Bazihizina N, Azzarello E, Petrucci WA, Masi E, Giordani E. Use of volatile organic compounds and physicochemical parameters for monitoring the post-harvest ripening of imported tropical fruits. Eur Food Res Technol 2015. [DOI: 10.1007/s00217-015-2438-6] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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Mancuso S, Taiti C, Bazihizina N, Costa C, Menesatti P, Giagnoni L, Arenella M, Nannipieri P, Renella G. Soil volatile analysis by proton transfer reaction-time of flight mass spectrometry (PTR-TOF-MS). Applied Soil Ecology 2015. [PMID: 0 DOI: 10.1016/j.apsoil.2014.10.018] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
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Bazihizina N, Redwan M, Taiti C, Giordano C, Monetti E, Masi E, Azzarello E, Mancuso S. Root based responses account for Psidium guajava survival at high nickel concentration. J Plant Physiol 2015; 174:137-146. [PMID: 25462976 DOI: 10.1016/j.jplph.2014.10.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/22/2014] [Revised: 10/27/2014] [Accepted: 10/28/2014] [Indexed: 06/04/2023]
Abstract
The presence of Psidium guajava in polluted environments has been reported in recent studies, suggesting that this species has a high tolerance to the metal stress. The present study aims at a physiological characterization of P. guajava response to high nickel (Ni) concentrations in the root-zone. Three hydroponic experiments were carried out to characterize the effects of toxic Ni concentrations on morphological and physiological parameters of P. guajava, focusing on Ni-induced damages at the root-level and root ion fluxes. With up to 300μM NiSO4 in the root-zone, plant growth was similar to that in control plants, whereas at concentrations higher than 1000μM NiSO4 there was a progressive decline in plant growth and leaf gas exchange parameters; this occurred despite, at all considered concentrations, plants limited Ni(2+) translocation to the shoot, therefore avoiding shoot Ni(2+) toxicity symptoms. Maintenance of plant growth with 300μM Ni(2+) was associated with the ability to retain K(+) in the roots meanwhile 1000 and 3000μM NiSO4 led to substantial K(+) losses. In this study, root responses mirror all plant performances suggesting a direct link between root functionality and Ni(2+) tolerance mechanisms and plant survival. Considering that Ni was mainly accumulated in the root system, the potential use of P. guajava for Ni(2+) phytoextraction in metal-polluted soils is limited; nevertheless, the observed physiological changes indicate a good Ni(2+) tolerance up to 300μM NiSO4 suggesting a potential role for the phytostabilization of polluted soils.
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Affiliation(s)
- Nadia Bazihizina
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Mirvat Redwan
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Cosimo Taiti
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Cristiana Giordano
- Centro di Microscopie Elettroniche "Laura Bonzi" (Ce.M.E.), ICCOM, CNR, Via Madonna del Piano, 50019 Sesto F.no, Florence, Italy
| | - Emanuela Monetti
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Elisa Masi
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Elisa Azzarello
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy.
| | - Stefano Mancuso
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
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Grasso DA, Pandolfi C, Bazihizina N, Nocentini D, Nepi M, Mancuso S. Extrafloral-nectar-based partner manipulation in plant-ant relationships. AoB Plants 2015; 7:plv002. [PMID: 25589521 PMCID: PMC4326690 DOI: 10.1093/aobpla/plv002] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/08/2014] [Accepted: 12/17/2014] [Indexed: 05/27/2023]
Abstract
Plant-ant interactions are generally considered as mutualisms, with both parties gaining benefits from the association. It has recently emerged that some of these mutualistic associations have, however, evolved towards other forms of relationships and, in particular, that plants may manipulate their partner ants to make reciprocation more beneficial, thereby stabilizing the mutualism. Focusing on plants bearing extrafloral nectaries, we review recent studies and address three key questions: (i) how can plants attract potential partners and maintain their services; (ii) are there compounds in extrafloral nectar that could mediate partner manipulation; and (iii) are ants susceptible to such compounds? After reviewing the current knowledge on plant-ant associations, we propose a possible scenario where plant-derived chemicals, such as secondary metabolites, known to have an impact on animal brain, could have evolved in plants to attract and manipulate ant behaviour. This new viewpoint would place plant-animal interaction in a different ecological context, opening new ecological and neurobiological perspectives of drug seeking and use.
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Affiliation(s)
- D A Grasso
- Department of Life Sciences, University of Parma, Viale delle Scienze 11/a, 43124 Parma, Italy
| | - C Pandolfi
- LINV - Department of Agrifood Production and Environmental Sciences, University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - N Bazihizina
- LINV - Department of Agrifood Production and Environmental Sciences, University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - D Nocentini
- Department of Life Science, University of Siena, Via P.A. Mattioli 4, 53100 Siena, Italy
| | - M Nepi
- Department of Life Science, University of Siena, Via P.A. Mattioli 4, 53100 Siena, Italy
| | - S Mancuso
- LINV - Department of Agrifood Production and Environmental Sciences, University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
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Bazihizina N, Taiti C, Marti L, Rodrigo-Moreno A, Spinelli F, Giordano C, Caparrotta S, Gori M, Azzarello E, Mancuso S. Zn2+ -induced changes at the root level account for the increased tolerance of acclimated tobacco plants. J Exp Bot 2014; 65:4931-42. [PMID: 24928985 PMCID: PMC4144771 DOI: 10.1093/jxb/eru251] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Evidence suggests that heavy-metal tolerance can be induced in plants following pre-treatment with non-toxic metal concentrations, but the results are still controversial. In the present study, tobacco plants were exposed to increasing Zn2+ concentrations (up to 250 and/or 500 μM ZnSO4) with or without a 1-week acclimation period with 30 μM ZnSO4. Elevated Zn2+ was highly toxic for plants, and after 3 weeks of treatments there was a marked (≥50%) decline in plant growth in non-acclimated plants. Plant acclimation, on the other hand, increased plant dry mass and leaf area up to 1.6-fold compared with non-acclimated ones. In non-acclimated plants, the addition of 250 μM ZnSO4 led to transient membrane depolarization and stomatal closure within 24h from the addition of the stress; by contrast, the acclimation process was associated with an improved stomatal regulation and a superior ability to maintain a negative root membrane potential, with values on average 37% more negative compared with non-acclimated plants. The different response at the plasma-membrane level between acclimated and non-acclimated plants was associated with an enhanced vacuolar Zn2+ sequestration and up to 2-fold higher expression of the tobacco orthologue of the Arabidopsis thaliana MTP1 gene. Thus, the acclimation process elicited specific detoxification mechanisms in roots that enhanced Zn2+ compartmentalization in vacuoles, thereby improving root membrane functionality and stomatal regulation in leaves following elevated Zn2+ stress.
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Affiliation(s)
- Nadia Bazihizina
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Cosimo Taiti
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Lucia Marti
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Ana Rodrigo-Moreno
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Francesco Spinelli
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Cristiana Giordano
- Centro di Microscopie Elettroniche 'Laura Bonzi' (Ce.M.E.), ICCOM, CNR, Via Madonna del Piano, 50019 Sesto F.no, Florence, Italy
| | - Stefania Caparrotta
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Massimo Gori
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Elisa Azzarello
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
| | - Stefano Mancuso
- LINV - Department of Agrifood Production and Environmental Sciences - University of Florence, Viale delle Idee 30, 50019 Sesto F.no, Florence, Italy
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Bazihizina N, Barrett-Lennard EG, Colmer TD. Plant responses to heterogeneous salinity: growth of the halophyte Atriplex nummularia is determined by the root-weighted mean salinity of the root zone. J Exp Bot 2012; 63:6347-58. [PMID: 23125356 PMCID: PMC3504498 DOI: 10.1093/jxb/ers302] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/04/2023]
Abstract
Soil salinity is generally spatially heterogeneous, but our understanding of halophyte physiology under such conditions is limited. The growth and physiology of the dicotyledonous halophyte Atriplex nummularia was evaluated in split-root experiments to test whether growth is determined by: (i) the lowest; (ii) the highest; or (iii) the mean salinity of the root zone. In two experiments, plants were grown with uniform salinities or horizontally heterogeneous salinities (10-450 mM NaCl in the low-salt side and 670 mM in the high-salt side, or 10 mM NaCl in the low-salt side and 500-1500 mM in the high-salt side). The combined data showed that growth and gas exchange parameters responded most closely to the root-weighted mean salinity rather than to the lowest, mean, or highest salinity in the root zone. In contrast, midday shoot water potentials were determined by the lowest salinity in the root zone, consistent with most water being taken from the least negative water potential source. With uniform salinity, maximum shoot growth was at 120-230 mM NaCl; ~90% of maximum growth occurred at 10 mM and 450 mM NaCl. Exposure of part of the roots to 1500 mM NaCl resulted in an enhanced (+40%) root growth on the low-salt side, which lowered root-weighted mean salinity and enabled the maintenance of shoot growth. Atriplex nummularia grew even with extreme salinity in part of the roots, as long as the root-weighted mean salinity of the root zone was within the 10-450 mM range.
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Affiliation(s)
- Nadia Bazihizina
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
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Bazihizina N, Colmer TD, Barrett-Lennard EG. Response to non-uniform salinity in the root zone of the halophyte Atriplex nummularia: growth, photosynthesis, water relations and tissue ion concentrations. Ann Bot 2009; 104:737-45. [PMID: 19556265 PMCID: PMC2729642 DOI: 10.1093/aob/mcp151] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2009] [Revised: 04/21/2009] [Accepted: 05/12/2009] [Indexed: 05/04/2023]
Abstract
BACKGROUND AND AIMS Soil salinity is often heterogeneous, yet the physiology of halophytes has typically been studied with uniform salinity treatments. An evaluation was made of the growth, net photosynthesis, water use, water relations and tissue ions in the halophytic shrub Atriplex nummularia in response to non-uniform NaCl concentrations in a split-root system. METHODS Atriplex nummularia was grown in a split-root system for 21 d, with either the same or two different NaCl concentrations (ranging from 10 to 670 mm), in aerated nutrient solution bathing each root half. KEY RESULTS Non-uniform salinity, with high NaCl in one root half (up to 670 mm) and 10 mm in the other half, had no effect on shoot ethanol-insoluble dry mass, net photosynthesis or shoot pre-dawn water potential. In contrast, a modest effect occurred for leaf osmotic potential (up to 30 % more solutes compared with uniform 10 mm NaCl treatment). With non-uniform NaCl concentrations (10/670 mm), 90 % of water was absorbed from the low salinity side, and the reduction in water use from the high salinity side caused whole-plant water use to decrease by about 30 %; there was no compensatory water uptake from the low salinity side. Leaf Na(+) and Cl(-) concentrations were 1.9- to 2.3-fold higher in the uniform 670 mm treatment than in the 10/670 mm treatment, whereas leaf K(+) concentrations were 1.2- to 2.0-fold higher in the non-uniform treatment. CONCLUSIONS Atriplex nummularia with one root half in 10 mm NaCl maintained net photosynthesis, shoot growth and shoot water potential even when the other root half was exposed to 670 mm NaCl, a concentration that inhibits growth by 65 % when uniform in the root zone. Given the likelihood of non-uniform salinity in many field situations, this situation would presumably benefit halophyte growth and physiology in saline environments.
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Affiliation(s)
- Nadia Bazihizina
- School of Plant Biology (M084)
- Centre for Ecohydrology (M084)
- Future Farm Industries Cooperative Research Centre, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - Timothy D. Colmer
- School of Plant Biology (M084)
- Future Farm Industries Cooperative Research Centre, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia
| | - Edward G. Barrett-Lennard
- School of Plant Biology (M084)
- Centre for Ecohydrology (M084)
- Department of Agriculture and Food of Western Australia
- Future Farm Industries Cooperative Research Centre, The University of Western Australia, 35 Stirling Highway, Crawley, WA, 6009, Australia
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