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Goggin DE, Cawthray GR, Busi R. Pyroxasulfone Metabolism in Resistant Lolium rigidum: Is It All Down to GST Activity? J Agric Food Chem 2024; 72:3937-3948. [PMID: 38354096 DOI: 10.1021/acs.jafc.3c08141] [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] [Indexed: 02/16/2024]
Abstract
Resistance to the herbicide pyroxasulfone has slowly but steadily increased in agricultural weeds. The evolved resistance of one Lolium rigidum population has been attributed to the conjugation of pyroxasulfone to reduced glutathione, mediated by glutathione transferase (GST) activity. To determine if GST-based metabolism is a widespread mechanism of pyroxasulfone resistance in L. rigidum, a number of putative-resistant populations were screened for GST activity toward pyroxasulfone, the presence of GSTF13-like isoforms (previously implicated in pyroxasulfone conjugation in this species), tissue glutathione concentrations, and response to inhibitors of GSTs and oxygenases. Although there were no direct correlations between pyroxasulfone resistance levels and these individual parameters, a random forest analysis indicated that GST activity was of primary importance for L. rigidum resistance to this herbicide.
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Affiliation(s)
- Danica E Goggin
- Australian Herbicide Resistance Initiative, School of Agriculture and Environment, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - Gregory R Cawthray
- Separation Science and Mass Spectrometry Facility, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - Roberto Busi
- Australian Herbicide Resistance Initiative, School of Agriculture and Environment, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
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Goggin DE, Cawthray GR, Busi R, Porri A, Beckie HJ. Enhanced production of water-soluble cinmethylin metabolites by Lolium rigidum populations with reduced cinmethylin sensitivity. Pest Manag Sci 2022; 78:3173-3182. [PMID: 35470951 PMCID: PMC9325456 DOI: 10.1002/ps.6947] [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] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 01/21/2022] [Revised: 04/10/2022] [Accepted: 04/26/2022] [Indexed: 06/14/2023]
Abstract
BACKGROUND Cinmethylin, a pre-emergence herbicide inhibiting fatty acid thioesterase activity, has recently been introduced to Australian cereal cropping for the control of Lolium rigidum Gaud. (annual ryegrass). To date, there have been no confirmed cases of cinmethylin resistance identified in this species, but some populations exhibit reduced sensitivity to this herbicide. To explore the mechanism which contributes to reduced sensitivity of annual ryegrass to cinmethylin, the extent and nature of cinmethylin metabolism, using carbon-14 (14 C)-labelled herbicide, were analysed in three reduced-sensitivity annual ryegrass populations, alongside a susceptible population and cinmethylin-tolerant wheat as controls. RESULTS All samples showed the same metabolite profile, with the extent of production of a specific water-soluble metabolite being correlated to the level of herbicide sensitivity. Application of the cytochrome P450 inhibitor phorate caused a decrease in water-soluble metabolite production as well as seedling growth in the presence of cinmethylin, indicating that reduced cinmethylin sensitivity in annual ryegrass could be wholly or partially due to oxidative modification of cinmethylin. CONCLUSION Because annual ryegrass has the potential to metabolize cinmethylin in the same way as wheat, careful stewardship is required to ensure the longevity of this herbicide. © 2022 The Authors. Pest Management Science published by John Wiley & Sons Ltd on behalf of Society of Chemical Industry.
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Affiliation(s)
- Danica E Goggin
- Australian Herbicide Resistance Initiative, School of Agriculture and EnvironmentUniversity of Western AustraliaPerthAustralia
| | - Gregory R Cawthray
- School of Biological SciencesUniversity of Western AustraliaPerthAustralia
| | - Roberto Busi
- Australian Herbicide Resistance Initiative, School of Agriculture and EnvironmentUniversity of Western AustraliaPerthAustralia
| | | | - Hugh J Beckie
- Australian Herbicide Resistance Initiative, School of Agriculture and EnvironmentUniversity of Western AustraliaPerthAustralia
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Falster D, Gallagher R, Wenk EH, Wright IJ, Indiarto D, Andrew SC, Baxter C, Lawson J, Allen S, Fuchs A, Monro A, Kar F, Adams MA, Ahrens CW, Alfonzetti M, Angevin T, Apgaua DMG, Arndt S, Atkin OK, Atkinson J, Auld T, Baker A, von Balthazar M, Bean A, Blackman CJ, Bloomfield K, Bowman DMJS, Bragg J, Brodribb TJ, Buckton G, Burrows G, Caldwell E, Camac J, Carpenter R, Catford JA, Cawthray GR, Cernusak LA, Chandler G, Chapman AR, Cheal D, Cheesman AW, Chen SC, Choat B, Clinton B, Clode PL, Coleman H, Cornwell WK, Cosgrove M, Crisp M, Cross E, Crous KY, Cunningham S, Curran T, Curtis E, Daws MI, DeGabriel JL, Denton MD, Dong N, Du P, Duan H, Duncan DH, Duncan RP, Duretto M, Dwyer JM, Edwards C, Esperon-Rodriguez M, Evans JR, Everingham SE, Farrell C, Firn J, Fonseca CR, French BJ, Frood D, Funk JL, Geange SR, Ghannoum O, Gleason SM, Gosper CR, Gray E, Groom PK, Grootemaat S, Gross C, Guerin G, Guja L, Hahs AK, Harrison MT, Hayes PE, Henery M, Hochuli D, Howell J, Huang G, Hughes L, Huisman J, Ilic J, Jagdish A, Jin D, Jordan G, Jurado E, Kanowski J, Kasel S, Kellermann J, Kenny B, Kohout M, Kooyman RM, Kotowska MM, Lai HR, Laliberté E, Lambers H, Lamont BB, Lanfear R, van Langevelde F, Laughlin DC, Laugier-Kitchener BA, Laurance S, Lehmann CER, Leigh A, Leishman MR, Lenz T, Lepschi B, Lewis JD, Lim F, Liu U, Lord J, Lusk CH, Macinnis-Ng C, McPherson H, Magallón S, Manea A, López-Martinez A, Mayfield M, McCarthy JK, Meers T, van der Merwe M, Metcalfe DJ, Milberg P, Mokany K, Moles AT, Moore BD, Moore N, Morgan JW, Morris W, Muir A, Munroe S, Nicholson Á, Nicolle D, Nicotra AB, Niinemets Ü, North T, O'Reilly-Nugent A, O'Sullivan OS, Oberle B, Onoda Y, Ooi MKJ, Osborne CP, Paczkowska G, Pekin B, Guilherme Pereira C, Pickering C, Pickup M, Pollock LJ, Poot P, Powell JR, Power SA, Prentice IC, Prior L, Prober SM, Read J, Reynolds V, Richards AE, Richardson B, Roderick ML, Rosell JA, Rossetto M, Rye B, Rymer PD, Sams MA, Sanson G, Sauquet H, Schmidt S, Schönenberger J, Schulze ED, Sendall K, Sinclair S, Smith B, Smith R, Soper F, Sparrow B, Standish RJ, Staples TL, Stephens R, Szota C, Taseski G, Tasker E, Thomas F, Tissue DT, Tjoelker MG, Tng DYP, de Tombeur F, Tomlinson K, Turner NC, Veneklaas EJ, Venn S, Vesk P, Vlasveld C, Vorontsova MS, Warren CA, Warwick N, Weerasinghe LK, Wells J, Westoby M, White M, Williams NSG, Wills J, Wilson PG, Yates C, Zanne AE, Zemunik G, Ziemińska K. AusTraits, a curated plant trait database for the Australian flora. Sci Data 2021; 8:254. [PMID: 34593819 PMCID: PMC8484355 DOI: 10.1038/s41597-021-01006-6] [Citation(s) in RCA: 22] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/14/2020] [Accepted: 08/05/2021] [Indexed: 02/08/2023] Open
Abstract
We introduce the AusTraits database - a compilation of values of plant traits for taxa in the Australian flora (hereafter AusTraits). AusTraits synthesises data on 448 traits across 28,640 taxa from field campaigns, published literature, taxonomic monographs, and individual taxon descriptions. Traits vary in scope from physiological measures of performance (e.g. photosynthetic gas exchange, water-use efficiency) to morphological attributes (e.g. leaf area, seed mass, plant height) which link to aspects of ecological variation. AusTraits contains curated and harmonised individual- and species-level measurements coupled to, where available, contextual information on site properties and experimental conditions. This article provides information on version 3.0.2 of AusTraits which contains data for 997,808 trait-by-taxon combinations. We envision AusTraits as an ongoing collaborative initiative for easily archiving and sharing trait data, which also provides a template for other national or regional initiatives globally to fill persistent gaps in trait knowledge.
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Affiliation(s)
- Daniel Falster
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia.
| | - Rachael Gallagher
- Department of Biological Sciences, Macquarie University, Sydney, Australia
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - Elizabeth H Wenk
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | - Ian J Wright
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | - Dony Indiarto
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | | | - Caitlan Baxter
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | - James Lawson
- NSW Department of Primary Industries, Orange, Australia
| | - Stuart Allen
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | - Anne Fuchs
- Centre for Australian National Biodiversity Research (a joint venture between Parks Australia and CSIRO), Canberra, ACT, Australia
| | - Anna Monro
- Centre for Australian National Biodiversity Research (a joint venture between Parks Australia and CSIRO), Canberra, ACT, Australia
| | - Fonti Kar
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | - Mark A Adams
- Swinburne University of Technology, Hawthorn, Australia
| | - Collin W Ahrens
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - Matthew Alfonzetti
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | | | - Deborah M G Apgaua
- Centre for Rainforest Studies, School for Field Studies, Yungaburra, Queensland, 4872, Australia
| | | | - Owen K Atkin
- The Australian National University, Canberra, Australia
| | - Joe Atkinson
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | - Tony Auld
- NSW Department of Planning Industry and Environment, Parramatta, Australia
| | | | - Maria von Balthazar
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | | | | | | | | | - Jason Bragg
- Research Centre for Ecosystem Resilience, Australian Institute of Botanical Science, Royal Botanic Gardens and Domain Trust, Sydney, Australia
| | | | | | | | | | - James Camac
- Centre of Excellence for Biosecurity Risk Analysis, The University of Melbourne, Melbourne, Australia
| | | | | | | | - Lucas A Cernusak
- College of Science and Engineering, James Cook University, Cairns, QLD, Australia
| | | | - Alex R Chapman
- Western Australian Herbarium, Keiran McNamara Conservation Science Centre, Department of Biodiversity, Conservation and Attractions, Western Australia, Kensington, Australia
| | - David Cheal
- Centre for Environmental Management, School of Health & Life Sciences, Federation University, Mount Helen, Australia
| | | | - Si-Chong Chen
- Royal Botanic Gardens, Richmond, Kew, United Kingdom
| | - Brendan Choat
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - Brook Clinton
- Centre for Australian National Biodiversity Research (a joint venture between Parks Australia and CSIRO), Canberra, ACT, Australia
| | - Peta L Clode
- University of Western Australia, Crawley, Australia
| | - Helen Coleman
- Western Australian Herbarium, Keiran McNamara Conservation Science Centre, Department of Biodiversity, Conservation and Attractions, Western Australia, Kensington, Australia
| | - William K Cornwell
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | | | - Michael Crisp
- The Australian National University, Canberra, Australia
| | - Erika Cross
- Charles Sturt University, Bathurst, Australia
| | - Kristine Y Crous
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - Saul Cunningham
- Fenner School of Environment and Society, The Australian National University, Canberra, Australia
| | | | - Ellen Curtis
- University of Technology Sydney, Sydney, Australia
| | - Matthew I Daws
- Environment Department, Alcoa of Australia, Huntly, Western Australia, Australia
| | - Jane L DeGabriel
- School of Marine and Tropical Biology, James Cook University, Douglas, Australia
| | - Matthew D Denton
- School of Agriculture, Food and Wine, University of Adelaide, Adelaide, Australia
| | - Ning Dong
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | | | - Honglang Duan
- Institute for Forest Resources & Environment of Guizhou, Guizhou University, Guiyang, China
| | | | - Richard P Duncan
- Institute for Applied Ecology, University of Canberra, ACT, 2617, Canberra, Australia
| | - Marco Duretto
- National Herbarium of New South Wales, Australian Institute of Botanical Science, Royal Botanic Gardens and Domain Trust, Sydney, Australia
| | - John M Dwyer
- School of Biological Sciences, The University of Queensland, St Lucia, Australia
| | | | | | - John R Evans
- The Australian National University, Canberra, Australia
| | - Susan E Everingham
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | | | - Jennifer Firn
- Queensland University of Technology, Brisbane, Australia
| | - Carlos Roberto Fonseca
- Departamento de Ecologia, Universidade Federal do Rio Grande do Norte, Natal, Natal - RN, Brazil
| | | | - Doug Frood
- Pathways Bushland and Environment Consultancy, Sydney, Australia
| | - Jennifer L Funk
- Department of Plant Sciences, University of California, Davis, USA
| | | | - Oula Ghannoum
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | | | - Carl R Gosper
- Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions, Kensington, WA, Australia
| | - Emma Gray
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | | | - Saskia Grootemaat
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | | | - Greg Guerin
- Terrestrial Ecosystem Research Network, The School of Biological Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia
| | - Lydia Guja
- Centre for Australian National Biodiversity Research (a joint venture between Parks Australia and CSIRO), Canberra, ACT, Australia
| | - Amy K Hahs
- School of Ecosystem and Forest Sciences, The University of Melbourne, Melbourne, Australia
| | | | | | - Martin Henery
- arks Australia, Department of Agriculture, Water and the Environment, Hobart, Australia
| | - Dieter Hochuli
- School of Life and Environmental Sciences, The University of Sydney, Camperdown, Australia
| | | | - Guomin Huang
- Nanchang Institute of Technology, Nanchang, China
| | - Lesley Hughes
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | - John Huisman
- Western Australian Herbarium, Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions, Kensington, Western Australia, Australia
| | | | - Ashika Jagdish
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | - Daniel Jin
- School of Life and Environmental Sciences, The University of Sydney, Camperdown, Australia
| | | | - Enrique Jurado
- Universidad Autonoma de Nuevo Leon, San Nicolás de los Garza, Mexico
| | | | | | - Jürgen Kellermann
- State Herbarium of South Australia, Botanic Gardens and State Herbarium, Hackney Road, Adelaide, SA, 5000, Australia
| | | | - Michele Kohout
- Department of Environment, Land, Water and Planning, Victoria, Australia
| | - Robert M Kooyman
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | - Martyna M Kotowska
- Department of Plant Ecology and Ecosystems Research, University of Goettingen, Göttingen, Germany
| | - Hao Ran Lai
- University of Canterbury, Christchurch, New Zealand
| | - Etienne Laliberté
- Institut de recherche en biologie végétale, Université de Montréal, 4101 Sherbrooke Est, Montréal, H1X 2B2, Canada
| | - Hans Lambers
- University of Western Australia, Crawley, Australia
| | | | - Robert Lanfear
- Ecology and Evolution, Research School of Biology, Australian National University, Canberra, Australia
| | - Frank van Langevelde
- Wildlife Ecology & Conservation Group, Wageningen University, Wageningen, The Netherlands
| | - Daniel C Laughlin
- Department of Botany, University of Wyoming, Laramie, WY, 82071, USA
| | | | | | | | - Andrea Leigh
- University of Technology Sydney, Sydney, Australia
| | | | - Tanja Lenz
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | - Brendan Lepschi
- Centre for Australian National Biodiversity Research (a joint venture between Parks Australia and CSIRO), Canberra, ACT, Australia
| | | | - Felix Lim
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), Université de Montpellier, CIRAD, CNRS, INRA, IRD, Montpellier, France
| | | | | | - Christopher H Lusk
- Environmental Research Institute, University of Waikato, Hamilton, New Zealand
| | | | - Hannah McPherson
- National Herbarium of New South Wales, Australian Institute of Botanical Science, Royal Botanic Gardens and Domain Trust, Sydney, Australia
| | - Susana Magallón
- Laboratorio Nacional de Ciencias de la Sostenibilidad, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Anthony Manea
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | - Andrea López-Martinez
- Laboratorio Nacional de Ciencias de la Sostenibilidad, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Margaret Mayfield
- School of Biological Sciences, The University of Queensland, St Lucia, Australia
| | | | | | - Marlien van der Merwe
- Research Centre for Ecosystem Resilience, Australian Institute of Botanical Science, Royal Botanic Gardens and Domain Trust, Sydney, Australia
| | | | | | | | - Angela T Moles
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | - Ben D Moore
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | | | | | | | - Annette Muir
- Department of Environment, Land, Water and Planning, Victoria, Australia
| | - Samantha Munroe
- Terrestrial Ecosystem Research Network, The School of Biological Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia
| | | | - Dean Nicolle
- Currency Creek Arboretum, Currency Creek, Australia
| | | | - Ülo Niinemets
- Estonian University of Life Sciences, Tartu, Estonia
| | - Tom North
- Centre for Australian National Biodiversity Research (a joint venture between Parks Australia and CSIRO), Canberra, ACT, Australia
| | | | | | - Brad Oberle
- Division of Natural Sciences, New College of Florida, Sarasota, USA
| | - Yusuke Onoda
- Graduate School of Agriculture, Kyoto University, Kyoto, Japan
| | - Mark K J Ooi
- Centre for Ecosystem Science, School of Biological, Earth, and Environmental Sciences, UNSW, Sydney, Australia
| | - Colin P Osborne
- University of Sheffield, Department of Animal and Plant Sciences, Sheffield, United Kingdom
| | - Grazyna Paczkowska
- Western Australian Herbarium, Keiran McNamara Conservation Science Centre, Department of Biodiversity, Conservation and Attractions, Western Australia, Kensington, Australia
| | - Burak Pekin
- Istanbul Technical University, Eurasia Institute of Earth Sciences, Istanbul, Turkey
| | - Caio Guilherme Pereira
- Department of Civil and Environmental Engineering, Massachusetts Institute of Technology, Cambridge, USA
| | | | | | | | - Pieter Poot
- College of Science and Engineering, James Cook University, Cairns, QLD, Australia
| | - Jeff R Powell
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - Sally A Power
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | | | | | | | - Jennifer Read
- School of Biological Sciences, Monash University, Clayton, Australia
| | - Victoria Reynolds
- School of Biological Sciences, The University of Queensland, St Lucia, Australia
| | | | - Ben Richardson
- Western Australian Herbarium, Department of Biodiversity, Conservation and Attractions, Western Australia, Kensington, Australia
| | | | - Julieta A Rosell
- Laboratorio Nacional de Ciencias de la Sostenibilidad, Instituto de Ecología, Universidad Nacional Autónoma de México, Ciudad de México, Mexico
| | - Maurizio Rossetto
- National Herbarium of New South Wales, Australian Institute of Botanical Science, Royal Botanic Gardens and Domain Trust, Sydney, Australia
| | - Barbara Rye
- Western Australian Herbarium, Department of Biodiversity, Conservation and Attractions, Western Australia, Kensington, Australia
| | - Paul D Rymer
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - Michael A Sams
- School of Biological Sciences, The University of Queensland, St Lucia, Australia
| | - Gordon Sanson
- School of Biological Sciences, Monash University, Clayton, Australia
| | - Hervé Sauquet
- National Herbarium of New South Wales, Australian Institute of Botanical Science, Royal Botanic Gardens and Domain Trust, Sydney, Australia
| | - Susanne Schmidt
- School of Agriculture and Food Science, University of Queensland, St Lucia, Australia
| | - Jürg Schönenberger
- Department of Botany and Biodiversity Research, University of Vienna, Vienna, Austria
| | | | - Kerrie Sendall
- Rider University, Lawrence Township, Lawrenceville, NJ, USA
| | - Steve Sinclair
- Department of Plant Ecology and Ecosystems Research, University of Goettingen, Göttingen, Germany
| | - Benjamin Smith
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - Renee Smith
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | | | - Ben Sparrow
- Terrestrial Ecosystem Research Network, The School of Biological Sciences, The University of Adelaide, Adelaide, SA, 5005, Australia
| | - Rachel J Standish
- Environmental and Conservation Sciences, Murdoch University, Murdoch, Australia
| | - Timothy L Staples
- School of Biological Sciences, The University of Queensland, St Lucia, Australia
| | - Ruby Stephens
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | | | - Guy Taseski
- Evolution & Ecology Research Centre, School of Biological, Earth, and Environmental Sciences, UNSW Sydney, Sydney, Australia
| | - Elizabeth Tasker
- NSW Department of Planning Industry and Environment, Parramatta, Australia
| | | | - David T Tissue
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - Mark G Tjoelker
- Hawkesbury Institute for the Environment, Western Sydney University, Sydney, Australia
| | - David Yue Phin Tng
- Centre for Rainforest Studies, School for Field Studies, Yungaburra, Queensland, 4872, Australia
| | - Félix de Tombeur
- TERRA Teaching and Research Centre, Gembloux Agro-Bio Tech, University of Liege, Gembloux, Belgium
| | | | | | | | - Susanna Venn
- Centre for Integrative Ecology, School of Life and Environmental Sciences, Deakin University, Burwood, Australia
| | - Peter Vesk
- University of Melbourne, Melbourne, Australia
| | - Carolyn Vlasveld
- School of Biological Sciences, Monash University, Clayton, Australia
| | | | - Charles A Warren
- School of Life and Environmental Sciences, The University of Sydney, Camperdown, Australia
| | | | | | - Jessie Wells
- School of Biological Sciences, The University of Queensland, St Lucia, Australia
| | - Mark Westoby
- Department of Biological Sciences, Macquarie University, Sydney, Australia
| | - Matthew White
- Department of Environment, Land, Water and Planning, Victoria, Australia
| | | | - Jarrah Wills
- School of Life and Environmental Sciences, The University of Sydney, Camperdown, Australia
| | - Peter G Wilson
- National Herbarium of NSW and Royal Botanic Gardens and Domain Trust, Sydney, Australia
| | - Colin Yates
- Biodiversity and Conservation Science, Department of Biodiversity, Conservation and Attractions, Kensington, WA, Australia
| | - Amy E Zanne
- Department of Biological Sciences, George Washington University, Washington, DC, 20052, USA
- Department of Biology, University of Miami, Coral Gables, Florida 33146 USA, George Washington University, Washington, DC, 20052, USA
| | | | - Kasia Ziemińska
- AMAP (Botanique et Modélisation de l'Architecture des Plantes et des Végétations), Université de Montpellier, CIRAD, CNRS, INRA, IRD, Montpellier, France
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Goggin DE, Cawthray GR, Flematti GR, Bringans SD, Lim H, Beckie HJ, Busi R. Pyroxasulfone-Resistant Annual Ryegrass ( Lolium rigidum) Has Enhanced Capacity for Glutathione Transferase-Mediated Pyroxasulfone Conjugation. J Agric Food Chem 2021; 69:6414-6422. [PMID: 34081453 DOI: 10.1021/acs.jafc.0c07458] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 05/23/2023]
Abstract
The herbicide pyroxasulfone was widely introduced in 2012, and cases of evolved resistance in weeds such as annual ryegrass (Lolium rigidum Gaud.) and tall waterhemp [Amaranthus tuberculatus (Moq.) Sauer] have started to emerge. Pyroxasulfone is detoxified by tolerant crops, and by annual ryegrass that has been recurrently selected with pyroxasulfone, in a pathway that is hypothesized to involve glutathione conjugation. In the current study, it was confirmed that pyroxasulfone is conjugated to glutathione in vitro by glutathione transferases (GSTs) purified from susceptible and resistant annual ryegrass populations and from a tolerant crop species, wheat. The extent of conjugation corresponded to the pyroxasulfone resistance level. Pyroxasulfone-conjugating activity was higher in radicles, roots, and seeds compared to coleoptiles or expanded leaves. Among the GSTs purified from annual ryegrass radicles and seeds, an orthologue of Brachypodium distachyon GSTF13 was >20-fold more abundant in the pyroxasulfone-resistant population, suggesting that this protein could be responsible for pyroxasulfone conjugation.
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Affiliation(s)
- Danica E Goggin
- Australian Herbicide Resistance Initiative, School of Agriculture and Environment, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - Gregory R Cawthray
- School of Biological Sciences, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - Gavin R Flematti
- School of Molecular Sciences, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - Scott D Bringans
- Proteomics International, 6 Verdun Street, Nedlands 6009, Australia
| | - Hitormi Lim
- Proteomics International, 6 Verdun Street, Nedlands 6009, Australia
| | - Hugh J Beckie
- Australian Herbicide Resistance Initiative, School of Agriculture and Environment, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - Roberto Busi
- Australian Herbicide Resistance Initiative, School of Agriculture and Environment, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
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5
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Alemneh AA, Cawthray GR, Zhou Y, Ryder MH, Denton MD. Ability to produce indole acetic acid is associated with improved phosphate solubilising activity of rhizobacteria. Arch Microbiol 2021; 203:3825-3837. [PMID: 33997908 DOI: 10.1007/s00203-021-02364-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/28/2021] [Accepted: 05/07/2021] [Indexed: 10/21/2022]
Abstract
Indole acetic acid (IAA) can upregulate genes encoding enzymes responsible for the synthesis of carboxylates involved in phosphorus (P) solubilisation. Here, we investigated whether IAA and its precursor affect the P-solubilising activity of rhizobacteria. A total of 841 rhizobacteria were obtained using taxonomically selective and enrichment isolation methods. Phylogenetic analysis revealed 15 genera of phosphate solubilising bacteria (PSB) capable of producing a wide range of IAA concentrations between 4.1 and 67.2 µg mL-1 in vitro. Addition of L-tryptophan to growth media improved the P-solubilising activity of PSB that were able to produce IAA greater than 20 µg mL-1. This effect was connected to the drop of pH and release of a high concentration of carboxylates, comprising α-ketoglutarate, cis-aconitate, citrate, malate and succinate. An increase in production of organic acids rather than IAA production per se appears to result in the improved P solubilisation in PSB.
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Affiliation(s)
- Anteneh Argaw Alemneh
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, SA, 5064, Australia.,China-Australia Joint Laboratory for Soil Ecological Health and Remediation, The University of Adelaide, Glen Osmond, SA, 5064, Australia
| | - Gregory R Cawthray
- School of Biological Sciences, The University of Western Australia, 35 Stirling Hwy, Crawley, Perth, WA, 6009, Australia
| | - Yi Zhou
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, SA, 5064, Australia. .,China-Australia Joint Laboratory for Soil Ecological Health and Remediation, The University of Adelaide, Glen Osmond, SA, 5064, Australia.
| | - Maarten H Ryder
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, SA, 5064, Australia.,China-Australia Joint Laboratory for Soil Ecological Health and Remediation, The University of Adelaide, Glen Osmond, SA, 5064, Australia
| | - Matthew D Denton
- School of Agriculture, Food and Wine, The University of Adelaide, Glen Osmond, SA, 5064, Australia.,China-Australia Joint Laboratory for Soil Ecological Health and Remediation, The University of Adelaide, Glen Osmond, SA, 5064, Australia
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Gao J, Wang F, Ranathunge K, Arruda AJ, Cawthray GR, Clode PL, He X, Leopold M, Roessner U, Rupasinghe T, Zhong H, Lambers H. Edaphic niche characterization of four Proteaceae reveals unique calcicole physiology linked to hyper-endemism of Grevillea thelemanniana. New Phytol 2020; 228:869-883. [PMID: 32726881 DOI: 10.1111/nph.16833] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [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: 04/20/2020] [Accepted: 07/15/2020] [Indexed: 06/11/2023]
Abstract
Endemism and rarity have long intrigued scientists. We focused on a rare endemic and critically-endangered species in a global biodiversity hotspot, Grevillea thelemanniana (Proteaceae). We carried out plant and soil analyses of four Proteaceae, including G. thelemanniana, and combined these with glasshouse studies. The analyses related to hydrology and plant water relations as well as soil nutrient concentrations and plant nutrition, with an emphasis on sodium (Na) and calcium (Ca). The local hydrology and matching plant traits related to water relations partially accounted for the distribution of the four Proteaceae. What determined the rarity of G. thelemanniana, however, was its accumulation of Ca. Despite much higher total Ca concentrations in the leaves of the rare G. thelemanniana than in the common Proteaceae, very few Ca crystals were detected in epidermal or mesophyll cells. Instead of crystals, G. thelemanniana epidermal cell vacuoles contained exceptionally high concentrations of noncrystalline Ca. Calcium ameliorated the negative effects of Na on the very salt-sensitive G. thelemanniana. Most importantly, G. thelemanniana required high concentrations of Ca to balance a massively accumulated feeding-deterrent carboxylate, trans-aconitate. This is the first example of a calcicole species accumulating and using Ca to balance accumulation of an antimetabolite.
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Affiliation(s)
- Jingwen Gao
- School of Biological Sciences, University of Western Australia, Crawley, Perth, WA, 6009, Australia
- Environmental Resources and Soil Fertilizer Institute, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Feng Wang
- School of Biological Sciences, University of Western Australia, Crawley, Perth, WA, 6009, Australia
- Environmental Resources and Soil Fertilizer Institute, Zhejiang Academy of Agricultural Sciences, Hangzhou, 310021, China
| | - Kosala Ranathunge
- School of Biological Sciences, University of Western Australia, Crawley, Perth, WA, 6009, Australia
| | - André J Arruda
- School of Biological Sciences, University of Western Australia, Crawley, Perth, WA, 6009, Australia
| | - Gregory R Cawthray
- School of Biological Sciences, University of Western Australia, Crawley, Perth, WA, 6009, Australia
| | - Peta L Clode
- School of Biological Sciences, University of Western Australia, Crawley, Perth, WA, 6009, Australia
- Centre for Microscopy, Characterisation and Analysis, University of Western Australia, Crawley, Perth, WA, 6009, Australia
| | - Xinhua He
- Center of Excellence for Soil Biology, College of Resources and Environment, Southwest University, Beibei, Chongqing, 400715, China
| | - Matthias Leopold
- UWA School of Agriculture and Environment, University of Western Australia, Crawley, Perth, WA, 6009, Australia
| | - Ute Roessner
- School of BioSciences, The University of Melbourne, Parkville, Melbourne, Vic, 3010, Australia
| | - Thusitha Rupasinghe
- School of BioSciences, The University of Melbourne, Parkville, Melbourne, Vic, 3010, Australia
| | - Hongtao Zhong
- School of Biological Sciences, University of Western Australia, Crawley, Perth, WA, 6009, Australia
| | - Hans Lambers
- School of Biological Sciences, University of Western Australia, Crawley, Perth, WA, 6009, Australia
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Płachno BJ, Stpiczyńska M, Świątek P, Lambers H, Cawthray GR, Nge FJ, Silva SR, Miranda VFO. Floral micromorphology and nectar composition of the early evolutionary lineage Utricularia (subgenus Polypompholyx, Lentibulariaceae). Protoplasma 2019; 256:1531-1543. [PMID: 31190095 PMCID: PMC6820596 DOI: 10.1007/s00709-019-01401-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.4] [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: 04/01/2019] [Accepted: 06/04/2019] [Indexed: 05/20/2023]
Abstract
Utricularia (Lentibulariaceae) is a genus comprising around 240 species of herbaceous, carnivorous plants. Utricularia is usually viewed as an insect-pollinated genus, with the exception of a few bird-pollinated species. The bladderworts Utricularia multifida and U. tenella are interesting species because they represent an early evolutionary Utricularia branch and have some unusual morphological characters in their traps and calyx. Thus, our aims were to (i) determine whether the nectar sugar concentrations and composition in U. multifida and U. tenella are similar to those of other Utricularia species from the subgenera Polypompholyx and Utricularia, (ii) compare the nectary structure of U. multifida and U. tenella with those of other Utricularia species, and (iii) determine whether U. multifida and U. tenella use some of their floral trichomes as an alternative food reward for pollinators. We used light microscopy, histochemistry, and scanning and transmission electron microscopy to address those aims. The concentration and composition of nectar sugars were analysed using high-performance liquid chromatography. In all of the examined species, the floral nectary consisted of a spur bearing glandular trichomes. The spur produced and stored the nectar. We detected hexose-dominated (fructose + glucose) nectar in U. multifida and U. tenella as well as in U. violacea. In both U. multifida and U. tenella, there were trichomes that blocked the entrance into the throat and spur. Because these trichomes were rich in chromoplasts and contained lipid droplets, they may form an additional visual attractant. Bearing in mind the phylogenetic hypothesis for the genus, we suggest that an early ancestor of Utricularia had a nectariferous spur flower with a lower lip that formed a wide landing platform for bee pollinators.
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Affiliation(s)
- Bartosz J Płachno
- Department of Plant Cytology and Embryology, Institute of Botany, Faculty of Biology, Jagiellonian University in Kraków, 9 Gronostajowa St., 30-387, Cracow, Poland.
| | - Małgorzata Stpiczyńska
- Botanic Garden, Faculty of Biology, University of Warsaw, Al. Ujazdowskie 4, 00-478, Warsaw, Poland
| | - Piotr Świątek
- Department of Animal Histology and Embryology, University of Silesia in Katowice, 9 Bankowa St., 40-007, Katowice, Poland
| | - Hans Lambers
- School of Biological Sciences, University of Western Australia, (M084) 35 Stirling Highway, Crawley Perth, WA, 6009, Australia
| | - Gregory R Cawthray
- School of Biological Sciences, University of Western Australia, (M084) 35 Stirling Highway, Crawley Perth, WA, 6009, Australia
| | - Francis J Nge
- School of Biological Sciences, Faculty of Science, The University of Adelaide, Adelaide, South Australia, 5005, Australia
| | - Saura R Silva
- Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, Departamento de Biologia Aplicada à Agropecuária, Universidade Estadual Paulista (Unesp), São Paulo, Brazil
| | - Vitor F O Miranda
- Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, Departamento de Biologia Aplicada à Agropecuária, Universidade Estadual Paulista (Unesp), São Paulo, Brazil
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8
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Płachno BJ, Stpiczyńska M, Świątek P, Lambers H, Miranda VFO, Nge FJ, Stolarczyk P, Cawthray GR. Floral micromorphology of the bird-pollinated carnivorous plant species Utricularia menziesii R.Br. (Lentibulariaceae). Ann Bot 2019; 123:213-220. [PMID: 30169570 PMCID: PMC6344090 DOI: 10.1093/aob/mcy163] [Citation(s) in RCA: 2] [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: 03/13/2018] [Accepted: 08/10/2018] [Indexed: 05/11/2023]
Abstract
BACKGROUND AND AIMS Bird pollination is rare among species in the genus Utricularia, and has evolved independently in two lineages of this genus. In Western Australia, the Western Spinebill, Acanthorhynchus superciliosus, visits flowers of Utricularia menziesii (section Pleiochasia: subgenus Polypompholyx). This study aimed to examine the micromorphology of U. menziesii flowers to assess traits that might be linked to its pollination strategy. METHODS Light microscopy, histochemistry and scanning electron microscopy were used. Nectar sugar composition was analysed using high-performance liquid chromatography. KEY RESULTS The flowers of U. menziesii fulfil many criteria that characterize bird-pollinated flowers: red colour, a large, tough nectary spur that can withstand contact with a hard beak, lack of visual nectar guides and fragrance. Trichomes at the palate and throat may act as tactile signals. Spur nectary trichomes did not form clearly visible patches, but were more frequently distributed along vascular bundles, and were small and sessile. Each trichome comprised a single basal cell, a unicellular short pedestal cell (barrier cell) and a multicelled head. These trichomes were much smaller than those of the U. vulgaris allies. Hexose-dominated nectar was detected in flower spurs. Fructose and glucose were present in equal quantities (43 ± 3.6 and 42 ± 3.6 g L-1). Sucrose was only detected in one sample, essentially at the limit of detection for the method used. This type of nectar is common in flowers pollinated by passerine perching birds. CONCLUSIONS The architecture of nectary trichomes in U. menziesii was similar to that of capitate trichomes of insect-pollinated species in this genus; thus, the most important specializations to bird pollination were flower colour (red), and both spur shape and size modification. Bird pollination is probably a recent innovation in the genus Utricularia, subgenus Polypompholyx, and is likely to have evolved from bee-pollinated ancestors.
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Affiliation(s)
- Bartosz J Płachno
- Department of Plant Cytology and Embryology, Jagiellonian University in Kraków, Cracow, Poland
- For correspondence. E-mail
| | - Małgorzata Stpiczyńska
- Botanic Garden, Faculty of Biology, University of Warsaw, Al. Ujazdowskie, Warsaw, Poland
| | - Piotr Świątek
- Department of Animal Histology and Embryology, University of Silesia in Katowice, Katowice, Poland
| | - Hans Lambers
- School of Biological Sciences, University of Western Australia (M084), Crawley (Perth), WA, Australia
| | - Vitor F O Miranda
- Universidade Estadual Paulista (Unesp), Faculdade de Ciências Agrárias e Veterinárias, Jaboticabal, Departamento de Biologia Aplicada à Agropecuária, São Paulo, Brazil
| | - Francis J Nge
- School of Biological Sciences, Faculty of Science, The University of Adelaide, Adelaide, South Australia, Australia
| | - Piotr Stolarczyk
- Unit of Botany and Plant Physiology, Institute of Plant Biology and Biotechnology, University of Agriculture in Kraków, Kraków, Poland
| | - Gregory R Cawthray
- School of Biological Sciences, University of Western Australia (M084), Crawley (Perth), WA, Australia
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9
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Goggin DE, Nealon GL, Cawthray GR, Scaffidi A, Howard MJ, Powles SB, Flematti GR. Identity and Activity of 2,4-Dichlorophenoxyacetic Acid Metabolites in Wild Radish ( Raphanus raphanistrum). J Agric Food Chem 2018; 66:13378-13385. [PMID: 30516986 DOI: 10.1021/acs.jafc.8b05300] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [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: 06/09/2023]
Abstract
Synthetic auxin herbicides, such as 2,4-dichlorophenoxyacetic acid (2,4-D), are widely used for selective control of broadleaf weeds in cereals and transgenic crops. Although the troublesome weed wild radish ( Raphanus raphanistrum) has developed resistance to 2,4-D, no populations have yet displayed an enhanced capacity for metabolic detoxification of the herbicide, with both susceptible and resistant wild radish plants readily metabolizing 2,4-D. Using mass spectrometry and nuclear magnetic resonance, the major 2,4-D metabolite was identified as the glucose ester, and its structure was confirmed by synthesis. As expected, both the endogenous and synthetic compounds retained auxin activity in a bioassay. The lack of detectable 2,4-D hydroxylation in wild radish and the lability of the glucose ester suggest that metabolic 2,4-D resistance is unlikely to develop in this species.
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Affiliation(s)
| | | | | | | | - Mark J Howard
- School of Chemistry , University of Leeds , Leeds LS2 9JT , United Kingdom
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10
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Del-Saz NF, Romero-Munar A, Cawthray GR, Palma F, Aroca R, Baraza E, Florez-Sarasa I, Lambers H, Ribas-Carbó M. Phosphorus concentration coordinates a respiratory bypass, synthesis and exudation of citrate, and the expression of high-affinity phosphorus transporters in Solanum lycopersicum. Plant Cell Environ 2018; 41:865-875. [PMID: 29380389 DOI: 10.1111/pce.13155] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [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: 05/18/2017] [Revised: 01/16/2018] [Accepted: 01/19/2018] [Indexed: 05/20/2023]
Abstract
Plants exhibit respiratory bypasses (e.g., the alternative oxidase [AOX]) and increase the synthesis of carboxylates in their organs (leaves and roots) in response to phosphorus (P) deficiency, which increases P uptake capacity. They also show differential expression of high-affinity inorganic phosphorus (Pi) transporters, thus avoiding P toxicity at a high P availability. The association between AOX and carboxylate synthesis was tested in Solanum lycopersicum plants grown at different soil P availability, by using plants grown under P-sufficient and P-limiting conditions and by applying a short-term (24 hr) P-sufficient pulse to plants grown under P limitation. Tests were also performed with plants colonized with arbuscular mycorrhizal fungi, which increased plant P concentration under reduced P availability. The in vivo activities of AOX and cytochrome oxidase were measured together with the concentration of carboxylates and the P concentration in plant organs. Gene transcription of Pi transporters (LePT1 and LePT2) was also studied. A coordinated response between plant P concentration with these traits was observed, indicating that a sufficient P availability in soil led to a suppression of both AOX activity and synthesis of citrate and a downregulation of the transcription of genes encoding high-affinity Pi transporters, presumably to avoid P toxicity.
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Affiliation(s)
- Néstor Fernández Del-Saz
- Grup de Recerca en Biologia de les Plantes en Condicions Mediterranies, Departament de Biologia, Universitat de les Illes Balears, Carretera de Valldemossa Km 7.5, Palma, 07122, Spain
| | - Antonia Romero-Munar
- Grup de Recerca en Biologia de les Plantes en Condicions Mediterranies, Departament de Biologia, Universitat de les Illes Balears, Carretera de Valldemossa Km 7.5, Palma, 07122, Spain
| | - Gregory R Cawthray
- School of Biological Sciences and Institute of Agriculture, University of Western Australia, 35 Stirling Highway, Crawley (Perth), Western Australia, 6009, Australia
| | - Francisco Palma
- Department of Plant Physiology, Facultad de Ciencias, University of Granada, Fuentenueva s/n, Granada, 18071, Spain
| | - Ricardo Aroca
- Department of Soil Microbiology and Symbiotic Systems, Estación Experimental del Zaidín-Consejo Superior de Investigaciones Científicas (EEZ-CSIC), Profesor Albareda 1, Granada, 18008, Spain
| | - Elena Baraza
- Grup de Recerca en Biologia de les Plantes en Condicions Mediterranies, Departament de Biologia, Universitat de les Illes Balears, Carretera de Valldemossa Km 7.5, Palma, 07122, Spain
| | - Igor Florez-Sarasa
- Max Planck Institut für Molekulare Pflanzenphysiologie, Am Mühlenberg 1, Potsdam, 14476, Germany
| | - Hans Lambers
- School of Biological Sciences and Institute of Agriculture, University of Western Australia, 35 Stirling Highway, Crawley (Perth), Western Australia, 6009, Australia
| | - Miquel Ribas-Carbó
- Grup de Recerca en Biologia de les Plantes en Condicions Mediterranies, Departament de Biologia, Universitat de les Illes Balears, Carretera de Valldemossa Km 7.5, Palma, 07122, Spain
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11
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Cambridge ML, Zavala-Perez A, Cawthray GR, Mondon J, Kendrick GA. Effects of high salinity from desalination brine on growth, photosynthesis, water relations and osmolyte concentrations of seagrass Posidonia australis. Mar Pollut Bull 2017; 115:252-260. [PMID: 27989371 DOI: 10.1016/j.marpolbul.2016.11.066] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [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: 09/12/2016] [Revised: 11/19/2016] [Accepted: 11/30/2016] [Indexed: 05/24/2023]
Abstract
Highly saline brines from desalination plants expose seagrass communities to salt stress. We examined effects of raised salinity (46 and 54psu) compared with seawater controls (37psu) over 6weeks on the seagrass, Posidonia australis, growing in tanks with the aim of separating effects of salinity from other potentially deleterious components of brine and determining appropriate bioindicators. Plants survived exposures of 2-4weeks at 54psu, the maximum salinity of brine released from a nearby desalination plant. Salinity significantly reduced maximum quantum yield of PSII (chlorophyll a fluorescence emissions). Leaf water potential (Ψw) and osmotic potential (Ψπ) were more negative at increased salinity, while turgor pressure (Ψp) was unaffected. Leaf concentrations of K+ and Ca2+ decreased, whereas concentrations of sugars (mainly sucrose) and amino acids increased. We recommend leaf osmolarity, ion, sugar and amino acid concentrations as bioindicators for salinity effects, associated with brine released in desalination plant outfalls.
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Affiliation(s)
- M L Cambridge
- UWA Oceans Institute and School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia.
| | - A Zavala-Perez
- UWA Oceans Institute and School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - G R Cawthray
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - J Mondon
- School of Life and Environmental Science, Deakin University, PO Box 423, Warrnambool, Victoria 3280, Australia
| | - G A Kendrick
- UWA Oceans Institute and School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
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12
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Gunasinghe N, You MP, Cawthray GR, Barbetti MJ. Cercosporin From Pseudocercosporella capsellae and its Critical Role in White Leaf Spot Development. Plant Dis 2016; 100:1521-1531. [PMID: 30686233 DOI: 10.1094/pdis-10-15-1192-re] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Pseudocercosporella capsellae, the causative agent of white leaf spot disease in Brassicaceae, can produce a purple-pink pigment on artificial media resembling, but not previously confirmed as, the toxin cercosporin. Chemical extraction with ethyl acetate from growing hyphae followed by quantitative (thin-layer chromatography [TLC] and high-performance liquid chromatography [HPLC]) and qualitative methods showed an identical absorption spectrum, with similar retardation factor (Rf) values on TLC papers and an identical peak with the same retention time in HPLC as for a standard for cercosporin. We believe this is the first report to confirm that the purple-pink pigment produced by P. capsellae is cercosporin. Confocal microscopy detected green autofluorescence of cercosporin-producing hyphae, confirming the presence of cercosporin inside hyphae. The highly virulent UWA Wlra-7 isolate of P. capsellae produced the greatest quantity of cercosporin (10.69 mg g-1). The phytotoxicity and role of cercosporin in disease initiation across each of three Brassicaceae host species (Brassica juncea, B. napus, and Raphanus raphanistrum) was also studied. Culture filtrates containing cercosporin were phytotoxic to all three host plant species, producing large, white lesions on highly sensitive B. juncea, only water-soaked areas on least sensitive R. raphanistrum, and intermediate lesions on B. napus. It is noteworthy that sensitivity to cercosporin of these three host species was analogous to their susceptibility to the pathogen, viz., B. juncea the most susceptible, R. raphanistrum the least susceptible, and B. napus intermediate. The presence of cercosporin in the inoculum significantly increased disease severity on the highly cercosporin-sensitive B. juncea. We believe that this is the first study to demonstrate that P. capsellae produces cercosporin in liquid culture rather than agar media. Finally, this study highlights an important role of cercosporin as a pathogenicity factor in white leaf spot disease on Brassicaceae as evidenced by the ability of the cercosporin-rich culture filtrate to reproduce white leaf spot lesions on host plants and by the enhanced virulence of P. capsellae in the presence of cercosporin.
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Affiliation(s)
- Niroshini Gunasinghe
- School of Plant Biology and the UWA Institute of Agriculture, Faculty of Science, The University of Western Australia, Crawley, WA 6009, Australia
| | - Ming Pei You
- School of Plant Biology and the UWA Institute of Agriculture, Faculty of Science, The University of Western Australia, Crawley, WA 6009, Australia
| | - Gregory R Cawthray
- School of Plant Biology and the UWA Institute of Agriculture, Faculty of Science, The University of Western Australia, Crawley, WA 6009, Australia
| | - Martin J Barbetti
- School of Plant Biology and the UWA Institute of Agriculture, Faculty of Science, The University of Western Australia, Crawley, WA 6009, Australia
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13
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Goggin DE, Cawthray GR, Powles SB. 2,4-D resistance in wild radish: reduced herbicide translocation via inhibition of cellular transport. J Exp Bot 2016; 67:3223-35. [PMID: 26994475 PMCID: PMC4892717 DOI: 10.1093/jxb/erw120] [Citation(s) in RCA: 57] [Impact Index Per Article: 7.1] [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: 05/19/2023]
Abstract
Resistance to auxinic herbicides is increasing in a range of dicotyledonous weed species, but in most cases the biochemical mechanism of resistance is unknown. Using (14)C-labelled herbicide, the mechanism of resistance to 2,4-dichlorophenoxyacetic acid (2,4-D) in two wild radish (Raphanus raphanistrum L.) populations was identified as an inability to translocate 2,4-D out of the treated leaf. Although 2,4-D was metabolized in wild radish, and in a different manner to the well-characterized crop species wheat and bean, there was no difference in metabolism between the susceptible and resistant populations. Reduced translocation of 2,4-D in the latter was also not due to sequestration of the herbicide, or to reduced uptake by the leaf epidermis or mesophyll cells. Application of auxin efflux or ABCB transporter inhibitors to 2,4-D-susceptible plants caused a mimicking of the reduced-translocation resistance phenotype, suggesting that 2,4-D resistance in the populations under investigation could be due to an alteration in the activity of a plasma membrane ABCB-type auxin transporter responsible for facilitating long-distance transport of 2,4-D.
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Affiliation(s)
- Danica E Goggin
- Australian Herbicide Resistance Initiative, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia School of Plant Biology, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - Gregory R Cawthray
- School of Plant Biology, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
| | - Stephen B Powles
- Australian Herbicide Resistance Initiative, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia School of Plant Biology, University of Western Australia, 35 Stirling Highway, Crawley 6009, Australia
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14
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Han H, Yu Q, Owen MJ, Cawthray GR, Powles SB. Widespread occurrence of both metabolic and target-site herbicide resistance mechanisms in Lolium rigidum populations. Pest Manag Sci 2016; 72:255-63. [PMID: 25703739 DOI: 10.1002/ps.3995] [Citation(s) in RCA: 43] [Impact Index Per Article: 5.4] [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: 11/11/2014] [Revised: 01/21/2015] [Accepted: 02/15/2015] [Indexed: 05/20/2023]
Abstract
BACKGROUND Lolium rigidum populations in Australia and globally have demonstrated rapid and widespread evolution of resistance to acetyl coenzyme A carboxylase (ACCase)-inhibiting and acetolactate synthase (ALS)-inhibiting herbicides. Thirty-three resistant L. rigidum populations, randomly collected from crop fields in a most recent resistance survey, were analysed for non-target-site diclofop metabolism and all known target-site ACCase gene resistance-endowing mutations. RESULTS The HPLC profile of [(14) C]-diclofop-methyl in vivo metabolism revealed that 79% of these resistant L. rigidum populations showed enhanced capacity for diclofop acid metabolism (metabolic resistance). ACCase gene sequencing identified that 91% of the populations contain plants with ACCase resistance mutation(s). Importantly, 70% of the populations exhibit both non-target-site metabolic resistance and target-site ACCase mutations. CONCLUSIONS This work demonstrates that metabolic herbicide resistance is commonly occurring in L. rigidum, and coevolution of both metabolic resistance and target-site resistance is an evolutionary reality. Metabolic herbicide resistance can potentially endow resistance to many herbicides and poses a threat to herbicide sustainability and thus crop production, calling for major research and management efforts.
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Affiliation(s)
- Heping Han
- Australian Herbicide Resistance Initiative, School of Plant Biology, University of Western Australia, Crawley, WA, Australia
| | - Qin Yu
- Australian Herbicide Resistance Initiative, School of Plant Biology, University of Western Australia, Crawley, WA, Australia
| | - Mechelle J Owen
- Australian Herbicide Resistance Initiative, School of Plant Biology, University of Western Australia, Crawley, WA, Australia
| | - Gregory R Cawthray
- School of Plant Biology, University of Western Australia, Crawley, WA, Australia
| | - Stephen B Powles
- Australian Herbicide Resistance Initiative, School of Plant Biology, University of Western Australia, Crawley, WA, Australia
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15
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Purnamasari M, Cawthray GR, Barbetti MJ, Erskine W, Croser JS. Camalexin Production in Camelina sativa is Independent of Cotyledon Resistance to Sclerotinia sclerotiorum. Plant Dis 2015; 99:1544-1549. [PMID: 30695949 DOI: 10.1094/pdis-12-14-1297-re] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Camelina sativa (L.) Crantz. has been proposed as a novel source of oilseed resistance to Sclerotinia rot (SR; causal agent Sclerotinia sclerotiorum (Lib.) de Bary). To assess factors likely important in determining the level of resistance to this pathogen, 30 diverse C. sativa genotypes were evaluated using a cotyledon test under controlled environmental conditions. Confirmed cotyledon SR-resistant (CS370) and SR-susceptible (CS2305) genotypes were assessed for camalexin production across time following inoculation at the 1-month vegetative stage of growth. There were significant differences among C. sativa genotypes in response to inoculation with S. sclerotiorum in terms of percent cotyledon disease index (%CDI), with the mean %CDI ranging from 30.9 to 69.4% across germplasm and confirmation screening, respectively. Genotype CS370 consistently showed low %CDI indicating high level of resistance to S. sclerotiorum, whereas CS2305 showed the highest %CDI value. These findings highlight the potential to develop highly SR-resistant cultivars of C. sativa by selection. Furthermore, liquid chromatographic analysis of leaves for both SR-resistant and SR-susceptible genotypes demonstrated that camalexin was produced when inoculated with S. sclerotiorum. However, camalexin production was not linked with disease severity in either genotype, indicating that SR resistance in C. sativa is independent of the level of camalexin production.
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Affiliation(s)
- Maria Purnamasari
- The University of Western Australia (UWA) Institute of Agriculture and School of Plant Biology, Faculty of Science, UWA, WA, 6009, Australia
| | - Gregory R Cawthray
- The University of Western Australia (UWA) Institute of Agriculture and School of Plant Biology, Faculty of Science, UWA, WA, 6009, Australia
| | - Martin J Barbetti
- The University of Western Australia (UWA) Institute of Agriculture and School of Plant Biology, Faculty of Science, UWA, WA, 6009, Australia
| | - William Erskine
- UWA Institute of Agriculture and Centre for Plant Genetics and Breeding, UWA
| | - Janine S Croser
- UWA Institute of Agriculture and Centre for Plant Genetics and Breeding, UWA
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16
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Sulpice R, Ishihara H, Schlereth A, Cawthray GR, Encke B, Giavalisco P, Ivakov A, Arrivault S, Jost R, Krohn N, Kuo J, Laliberté E, Pearse SJ, Raven JA, Scheible WR, Teste F, Veneklaas EJ, Stitt M, Lambers H. Low levels of ribosomal RNA partly account for the very high photosynthetic phosphorus-use efficiency of Proteaceae species. Plant Cell Environ 2014; 37:1276-98. [PMID: 24895754 PMCID: PMC4260170 DOI: 10.1111/pce.12240] [Citation(s) in RCA: 62] [Impact Index Per Article: 6.2] [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] [Indexed: 05/16/2023]
Abstract
Proteaceae species in south-western Australia occur on phosphorus- (P) impoverished soils. Their leaves contain very low P levels, but have relatively high rates of photosynthesis. We measured ribosomal RNA (rRNA) abundance, soluble protein, activities of several enzymes and glucose 6-phosphate (Glc6P) levels in expanding and mature leaves of six Proteaceae species in their natural habitat. The results were compared with those for Arabidopsis thaliana. Compared with A. thaliana, immature leaves of Proteaceae species contained very low levels of rRNA, especially plastidic rRNA. Proteaceae species showed slow development of the photosynthetic apparatus (‘delayed greening’), with young leaves having very low levels of chlorophyll and Calvin-Benson cycle enzymes. In mature leaves, soluble protein and Calvin-Benson cycle enzyme activities were low, but Glc6P levels were similar to those in A. thaliana. We propose that low ribosome abundance contributes to the high P efficiency of these Proteaceae species in three ways: (1) less P is invested in ribosomes; (2) the rate of growth and, hence, demand for P is low; and (3) the especially low plastidic ribosome abundance in young leaves delays formation of the photosynthetic machinery, spreading investment of P in rRNA. Although Calvin-Benson cycle enzyme activities are low, Glc6P levels are maintained, allowing their effective use.
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Affiliation(s)
- Ronan Sulpice
- Max Planck Institute of Molecular Plant PhysiologyAm Mühlenberg 1, Potsdam-Golm, D-14476, Germany
- * Present address: National University of Ireland, Galway, Plant
Systems Biology Lab, Plant and AgriBiosciences Research Centre, Botany and Plant Science, Galway, Ireland
| | - Hirofumi Ishihara
- Max Planck Institute of Molecular Plant PhysiologyAm Mühlenberg 1, Potsdam-Golm, D-14476, Germany
- † These three authors are joint first authors
| | - Armin Schlereth
- Max Planck Institute of Molecular Plant PhysiologyAm Mühlenberg 1, Potsdam-Golm, D-14476, Germany
- † These three authors are joint first authors
| | - Gregory R Cawthray
- School of Plant Biology, The University of Western Australia35 Stirling Highway, Crawley (Perth), Western Australia, 6009, Australia
| | - Beatrice Encke
- Max Planck Institute of Molecular Plant PhysiologyAm Mühlenberg 1, Potsdam-Golm, D-14476, Germany
| | - Patrick Giavalisco
- Max Planck Institute of Molecular Plant PhysiologyAm Mühlenberg 1, Potsdam-Golm, D-14476, Germany
| | - Alexander Ivakov
- Max Planck Institute of Molecular Plant PhysiologyAm Mühlenberg 1, Potsdam-Golm, D-14476, Germany
| | - StÉphanie Arrivault
- Max Planck Institute of Molecular Plant PhysiologyAm Mühlenberg 1, Potsdam-Golm, D-14476, Germany
| | - Ricarda Jost
- School of Plant Biology, The University of Western Australia35 Stirling Highway, Crawley (Perth), Western Australia, 6009, Australia
| | - Nicole Krohn
- Max Planck Institute of Molecular Plant PhysiologyAm Mühlenberg 1, Potsdam-Golm, D-14476, Germany
| | - John Kuo
- Centre for Microscopy and Microanalysis, The University of Western Australia35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Etienne Laliberté
- School of Plant Biology, The University of Western Australia35 Stirling Highway, Crawley (Perth), Western Australia, 6009, Australia
| | - Stuart J Pearse
- School of Plant Biology, The University of Western Australia35 Stirling Highway, Crawley (Perth), Western Australia, 6009, Australia
| | - John A Raven
- School of Plant Biology, The University of Western Australia35 Stirling Highway, Crawley (Perth), Western Australia, 6009, Australia
- Division of Plant Sciences, University of Dundee at JHI, James Hutton InstituteInvergowrie, Dundee, DD2 5DA, UK
| | - Wolf-rüdiger Scheible
- Max Planck Institute of Molecular Plant PhysiologyAm Mühlenberg 1, Potsdam-Golm, D-14476, Germany
- Plant Biology Division, The Samuel Roberts Noble Foundation2510 Sam Noble Parkway, Ardmore, OK, 73401, USA
| | - François Teste
- School of Plant Biology, The University of Western Australia35 Stirling Highway, Crawley (Perth), Western Australia, 6009, Australia
| | - Erik J Veneklaas
- School of Plant Biology, The University of Western Australia35 Stirling Highway, Crawley (Perth), Western Australia, 6009, Australia
| | - Mark Stitt
- Max Planck Institute of Molecular Plant PhysiologyAm Mühlenberg 1, Potsdam-Golm, D-14476, Germany
| | - Hans Lambers
- School of Plant Biology, The University of Western Australia35 Stirling Highway, Crawley (Perth), Western Australia, 6009, Australia
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17
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Han H, Yu Q, Cawthray GR, Powles SB. Enhanced herbicide metabolism induced by 2,4-D in herbicide susceptible Lolium rigidum provides protection against diclofop-methyl. Pest Manag Sci 2013; 69:996-1000. [PMID: 23785039 DOI: 10.1002/ps.3552] [Citation(s) in RCA: 6] [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: 11/15/2012] [Revised: 03/01/2013] [Accepted: 04/05/2013] [Indexed: 05/10/2023]
Abstract
BACKGROUND The auxinic herbicide 2,4-D amine is known, in vitro, as a cytochrome P450 inducer. The current study uses 2,4-D pre-treatment, at the whole plant level, to study mechanism(s) of non-target site based herbicide resistance to the ACCase-inhibiting herbicide diclofop-methyl in Lolium rigidum. RESULTS The 2,4-D pre-treatment caused up to 10-fold shift in LD50 and GR50 in dose-response to subsequently applied diclofop-methyl in a herbicide susceptible L. rigidum population. Foliar uptake and translocation of (14) C-diclofop-methyl did not differ in 2,4-D pre-treated versus untreated plants. HPLC analysis revealed that de-esterification of diclofop-methyl to toxic diclofop acid was similar, but further metabolism of diclofop acid to non-toxic metabolites was significantly (1.8-fold) faster in 2,4-D pre-treated than untreated plants. HPLC profile of major polar metabolites was similar when L. rigidum and diclofop-methyl tolerant wheat were compared, but wheat metabolised diclofop acid three-fold faster than L. rigidum. In addition, 2,4-D pre-treatment also induced cross-protection against the ALS-inhibiting herbicide chlorsulfuron, and the known P450 inhibitor malathion can reverse this effect. CONCLUSIONS Protection against diclofop-methyl provided by 2,4-D pre-treatment in susceptible L. rigidum is associated with higher rates of herbicide metabolism, mirroring that identified in field-evolved, non-target site-based diclofop-methyl resistant populations. 2,4-D may induce higher level expression of herbicide-metabolising genes hence providing protection, and therefore, this 2,4-D induction system can be used, in combination with other genomic approaches, to assist isolating cytochrome P450 and other genes that are involved in herbicide metabolism and endow herbicide resistance in L. rigidum.
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Affiliation(s)
- Heping Han
- Australian Herbicide Resistance Initiative, School of Plant Biology, Faculty of Natural and Agricultural Sciences, University of Western Australia, Crawley, WA 6009, Australia
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18
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Yu Q, Han H, Cawthray GR, Wang SF, Powles SB. Enhanced rates of herbicide metabolism in low herbicide-dose selected resistant Lolium rigidum. Plant Cell Environ 2013; 36:818-27. [PMID: 23046181 DOI: 10.1111/pce.12017] [Citation(s) in RCA: 20] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Lolium rigidum is an obligately cross-pollinated, genetically diverse species and an economically important herbicide resistance-prone weed. Our previous work has demonstrated that recurrent selection of initially susceptible L. rigidum populations with low herbicide rates results in rapid herbicide resistance evolution. Here we report on the mechanisms endowing low-dose-selected diclofop-methyl resistance in L. rigidum. Results showed that resistance was not due to target-site ACCase mutations or overproduction, or differential herbicide leaf uptake and translocation. The in vivo de-esterification of diclofop-methyl into phytotoxic diclofop acid was rapid and similar in resistant versus susceptible populations. However, further metabolism of diclofop acid into non-toxic metabolites was always faster in resistant plants than susceptible plants, resulting in up to 2.6-fold lower level of diclofop acid in resistant plants. This corresponded well with up to twofold higher level of diclofop acid metabolites in resistant plants. The major polar metabolites of diclofop acid chromatographically resembled those of wheat, a naturally tolerant species. Clearly, recurrent selection at reduced herbicide rates selected for non-target-site-based enhanced rates of herbicide metabolism, likely involving cytochrome P450 monooxygenases.
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Affiliation(s)
- Q Yu
- Australian Herbicide Resistance Initiative (M086) and School of Plant Biology, University of Western Australia, Crawley, WA 6009, Australia.
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19
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Lambers H, Cawthray GR, Giavalisco P, Kuo J, Laliberté E, Pearse SJ, Scheible WR, Stitt M, Teste F, Turner BL. Proteaceae from severely phosphorus-impoverished soils extensively replace phospholipids with galactolipids and sulfolipids during leaf development to achieve a high photosynthetic phosphorus-use-efficiency. New Phytol 2012; 196:1098-1108. [PMID: 22937909 DOI: 10.1111/j.1469-8137.2012.04285.x] [Citation(s) in RCA: 112] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2012] [Accepted: 07/20/2012] [Indexed: 05/20/2023]
Abstract
Proteaceae species in south-western Australia occur on severely phosphorus (P)-impoverished soils. They have very low leaf P concentrations, but relatively fast rates of photosynthesis, thus exhibiting extremely high photosynthetic phosphorus-use-efficiency (PPUE). Although the mechanisms underpinning their high PPUE remain unknown, one possibility is that these species may be able to replace phospholipids with nonphospholipids during leaf development, without compromising photosynthesis. For six Proteaceae species, we measured soil and leaf P concentrations and rates of photosynthesis of both young expanding and mature leaves. We also assessed the investment in galactolipids, sulfolipids and phospholipids in young and mature leaves, and compared these results with those on Arabidopsis thaliana, grown under both P-sufficient and P-deficient conditions. In all Proteaceae species, phospholipid levels strongly decreased during leaf development, whereas those of galactolipids and sulfolipids strongly increased. Photosynthetic rates increased from young to mature leaves. This shows that these species extensively replace phospholipids with nonphospholipids during leaf development, without compromising photosynthesis. A considerably less pronounced shift was observed in A. thaliana. Our results clearly show that a low investment in phospholipids, relative to nonphospholipids, offers a partial explanation for a high photosynthetic rate per unit leaf P in Proteaceae adapted to P-impoverished soils.
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Affiliation(s)
- Hans Lambers
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Gregory R Cawthray
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Patrick Giavalisco
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - John Kuo
- Centre for Microscopy and Microanalysis, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Etienne Laliberté
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Stuart J Pearse
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Wolf-Rüdiger Scheible
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
- Plant Biology Division, The Samuel Roberts Noble Foundation, Ardmore, OK, 73401, USA
| | - Mark Stitt
- Max Planck Institute of Molecular Plant Physiology, Am Mühlenberg 1, D-14476, Potsdam-Golm, Germany
| | - François Teste
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
| | - Benjamin L Turner
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley, Western Australia, 6009, Australia
- Smithsonian Tropical Research Institute, Apartado 0843-03092, Balboa, Ancón, Republic of Panama
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20
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Ryan MH, Tibbett M, Edmonds-Tibbett T, Suriyagoda LDB, Lambers H, Cawthray GR, Pang J. Carbon trading for phosphorus gain: the balance between rhizosphere carboxylates and arbuscular mycorrhizal symbiosis in plant phosphorus acquisition. Plant Cell Environ 2012; 35:2170-80. [PMID: 22632405 DOI: 10.1111/j.1365-3040.2012.02547.x] [Citation(s) in RCA: 59] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Two key plant adaptations for phosphorus (P) acquisition are carboxylate exudation into the rhizosphere and mycorrhizal symbioses. These target different soil P resources, presumably with different plant carbon costs. We examined the effect of inoculation with arbuscular mycorrhizal fungi (AMF) on amount of rhizosphere carboxylates and plant P uptake for 10 species of low-P adapted Kennedia grown for 23 weeks in low-P sand. Inoculation decreased carboxylates in some species (up to 50%), decreased plant dry weight (21%) and increased plant P content (23%). There was a positive logarithmic relationship between plant P content and the amount of rhizosphere citric acid for inoculated and uninoculated plants. Causality was indicated by experiments using sand where little citric acid was lost from the soil solution over 2 h and citric acid at low concentrations desorbed P into the soil solution. Senesced leaf P concentration was often low and P-resorption efficiencies reached >90%. In conclusion, we propose that mycorrhizally mediated resource partitioning occurred because inoculation reduced rhizosphere carboxylates, but increased plant P uptake. Hence, presumably, the proportion of plant P acquired from strongly sorbed sources decreased with inoculation, while the proportion from labile inorganic P increased. Implications for plant fitness under field conditions now require investigation.
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Affiliation(s)
- M H Ryan
- Schools of Plant Biology, Institute of Agriculture, Future Farm Industries Cooperative Research Centre, The University of Western Australia, Crawley, WA 6009.
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21
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Greenway H, Kulichikhin KY, Cawthray GR, Colmer TD. pH regulation in anoxic rice coleoptiles at pH 3.5: biochemical pHstats and net H+ influx in the absence and presence of NOFormula. J Exp Bot 2012; 63:1969-83. [PMID: 22174442 PMCID: PMC3295390 DOI: 10.1093/jxb/err395] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [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: 05/19/2011] [Revised: 10/23/2011] [Accepted: 11/09/2011] [Indexed: 05/08/2023]
Abstract
During anoxia, cytoplasmic pH regulation is crucial. Mechanisms of pH regulation were studied in the coleoptile of rice exposed to anoxia and pH 3.5, resulting in H(+) influx. Germinating rice seedlings survived a combination of anoxia and exposure to pH 3.5 for at least 4 d, although development was retarded and net K(+) efflux was continuous. Further experiments used excised coleoptile tips (7-10 mm) in anoxia at pH 6.5 or 3.5, either without or with 0.2 mM NO(3)(-), which distinguished two processes involved in pH regulation. Net H(+) influx (μmol g(-1) fresh weight h(-1)) for coleoptiles with NO(3)(-) was ∼1.55 over the first 24 h, being about twice that in the absence of NO(3)(-), but then decreased to 0.5-0.9 as net NO(3)(-) uptake declined from ∼1.3 to 0.5, indicating reduced uptake via H(+)-NO(3)(-) symports. NO(3)(-) reduction presumably functioned as a biochemical pHstat. A second biochemical pHstat consisted of malate and succinate, and their concentrations decreased substantially with time after exposure to pH 3.5. In anoxic coleoptiles, K(+) balancing the organic anions was effluxed to the medium as organic anions declined, and this efflux rate was independent of NO(3)(-) supply. Thus, biochemical pHstats and reduced net H(+) influx across the plasma membrane are important features contributing to pH regulation in anoxia-tolerant rice coleoptiles at pH 3.5.
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Affiliation(s)
| | | | | | - Timothy D. Colmer
- School of Plant Biology, Faculty of Natural and Agricultural Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, 6009 WA, Australia
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22
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Nio SA, Cawthray GR, Wade LJ, Colmer TD. Pattern of solutes accumulated during leaf osmotic adjustment as related to duration of water deficit for wheat at the reproductive stage. Plant Physiol Biochem 2011; 49:1126-1137. [PMID: 21741263 DOI: 10.1016/j.plaphy.2011.05.011] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/03/2011] [Accepted: 05/26/2011] [Indexed: 05/27/2023]
Abstract
This study examined expression of osmotic adjustment (OA) and accumulation of solutes in wheat (Triticum aestivum L.) leaves in response to water deficit (WD) imposed at the reproductive stage. Two contrasting cultivars, Hartog and Sunco (putatively high and low in OA capacity, respectively), were grown in deep (viz. 80 cm) pots in a controlled environment. In a sandy substrate, leaf OA was 5-times greater in Hartog compared with Sunco. At 21 d of WD treatment, K(+) only accounted for 12% of OA in Hartog and 48% in Sunco with less OA (i.e. tissue K(+) led to different proportions owing to different magnitudes of OA). Glycinebetaine and proline also increased under WD, but these were not significant osmotica on a whole tissue basis. Hartog accumulated dry matter faster than Sunco under WD, and this was consistent with greater water extraction by Hartog than by Sunco. In a second experiment on Hartog, with loam added to the sand to increase water-holding capacity and thus enable a longer draw-down period, leaf OA increased to 0.37 MPa at 37 d of withholding water. K(+) increased up to 16 d of drying and then decreased towards 37 d. Glycinebetaine, proline, glucose and fructose all increased during the draw-down period, although with different dynamics; e.g. glycinebetaine increased linearly whereas glucose showed an exponential increase. By contrast, sucrose declined. K(+) was the major contributor to OA (viz. 54%) up to 30 d of drying, whereas glycinebetaine, proline and glucose were major contributors later (at d 37 these organic solutes each accounted for 19, 21 and 21% of OA). Thus, the various solutes that contributed to leaf OA in wheat cv. Hartog accumulated at different times as WD developed.
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Affiliation(s)
- S A Nio
- School of Plant Biology and The UWA Institute of Agriculture, Faculty of Natural and Agricultural Sciences, The University of Western Australia, Crawley, WA 6009, Australia
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23
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Shane MW, McCully ME, Canny MJ, Pate JS, Ngo H, Mathesius U, Cawthray GR, Lambers H. Summer dormancy and winter growth: root survival strategy in a perennial monocotyledon. New Phytol 2009; 183:1085-1096. [PMID: 19496944 DOI: 10.1111/j.1469-8137.2009.02875.x] [Citation(s) in RCA: 10] [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] [Indexed: 05/27/2023]
Abstract
Here, we tested the alternation of root summer dormancy and winter growth as a critical survival strategy for a long-lived monocotyledon (Restionaceae) adapted to harsh seasonal extremes of Mediterranean southwest Western Australia. Measurements of growth and the results of comparative studies of the physiology, water content, metabolites, osmotic adjustments, and proteomics of the dormant and growing perennial roots of Lyginia barbata (Restionaceae) were assessed in field-grown plants. Formation of dormant roots occurred before the onset of summer extremes. They resumed growth (average 2.3 mm d(-1)) the following winter to eventually reach depths of 2-4 m. Compared with winter-growing roots, summer dormant roots had decreased respiration and protein concentration and c. 70% water content, sustained by sand-sheaths, osmotic adjustment and presumably hydraulic redistribution. Concentrations of compatible solutes (e.g. sucrose and proline) were significantly greater during dormancy, presumably mitigating the effects of heat and drought. Fifteen root proteins showed differential abundance and were correlated with either winter growth or summer dormancy. None matched currently available libraries. The specific features of the root dormancy strategy of L. barbata revealed in this study are likely to be important to understanding similar behaviour in roots of many long-lived monocotyledons, including overwintering and oversummering crop species.
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Affiliation(s)
- Michael W Shane
- School of Plant Biology, M084, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | | | - Martin J Canny
- Functional Ecology Group, Research School of Biological Sciences, Australian National University, Canberra, ACT 0200, Australia
| | - John S Pate
- School of Plant Biology, M084, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Hai Ngo
- School of Plant Biology, M084, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Ulrike Mathesius
- School of Biochemistry and Molecular Biology, Australian National University and Australian Research Council Centre of Excellence for Integrative Legume Research, Linnaeus Way, Canberra, ACT 0200, Australia
| | - Gregory R Cawthray
- School of Plant Biology, M084, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
| | - Hans Lambers
- School of Plant Biology, M084, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia
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Shane MW, Cawthray GR, Cramer MD, Kuo J, Lambers H. Specialized 'dauciform' roots of Cyperaceae are structurally distinct, but functionally analogous with 'cluster' roots. Plant Cell Environ 2006; 29:1989-99. [PMID: 16930324 DOI: 10.1111/j.1365-3040.2006.01574.x] [Citation(s) in RCA: 44] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
When grown in nutrient solutions of extremely low [P] (<or=1.0 microm), the sedge Schoenus unispiculatus Benth. (Cyperaceae) develops dauciform roots, which are short and carrot shaped, and produce dense numbers of long root hairs. It has been suggested that dauciform roots of monocotyledonous sedges function to acquire P from nutrient-poor, P-fixing soils in a manner similar to that of cluster (proteoid) roots developed by some dicotyledonous species, but without evidence to substantiate this claim. To elucidate the ecophysiological role of dauciform roots, we assessed carboxylate exudation, internal carboxylate and P concentrations and O(2) uptake rates during dauciform root development. We showed that O(2) consumption was fastest [9 nmol O(2) g(-1) fresh mass (FM) s(-1)] and root [P] greatest (0.4 mg P g(-1) FM) when dauciform roots were young and rapidly developing. Citrate was the most abundant carboxylate in root tissues at all developmental stages, and was most concentrated (22.2 micromol citrate g(-1) FM) in young dauciform roots, decreasing by more than half in mature dauciform roots. Peak citrate-exudation rates (1.7 nmol citrate g(-1) FM s(-1)) occurred from mature dauciform roots, and were approximately an order of magnitude faster than those from roots of species without root clusters, and similar to those of mature proteoid (cluster) roots of Proteaceae. Both developing and mature dauciform roots had the capacity to acidify (but not alkalinize) the rhizosphere. Anatomical studies showed that epidermal cells in dauciform roots were greatly elongated in the transverse plane; epidermal cells of parent roots were unmodified. Although structurally distinct, the physiology of dauciform roots in sedges appears to be analogous to that of proteoid roots of Proteaceae and Fabaceae, and hence, dauciform roots would facilitate access to sorbed P and micronutrients from soils of low fertility.
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Affiliation(s)
- Michael W Shane
- School of Plant Biology, Faculty of Natural and Agricultural Sciences
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25
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Heliyanto B, Krauss SL, Lambers H, Cawthray GR, Veneklaas EJ. Increased ecological amplitude through heterosis following wide outcrossing in Banksia ilicifolia R.Br. (Proteaceae). J Evol Biol 2006; 19:1327-38. [PMID: 16780533 DOI: 10.1111/j.1420-9101.2005.01067.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
To assess whether wide outcrossing (over 30 km) in the naturally fragmented Banksia ilicifolia R.Br. increases the ecological amplitude of offspring, we performed a comparative greenhouse growth study involving seedlings of three hand-pollinated progeny classes (self, local outcross, wide outcross) and a range of substrates and stress conditions. Outcrossed seedlings outperformed selfed seedlings, with the magnitude of inbreeding depression as high as 62% for seed germination and 37% for leaf area. Wide outcrossed seedlings outperformed local outcrossed seedlings, especially in non-native soils, facilitated in part by an improved capacity to overcome soil constraints through greater root carboxylate exudation. Soil type significantly affected seedling growth, and waterlogging and water deficit decreased growth, production of cluster roots, root exudation and total plant P uptake. Our results suggest that the interaction of narrow ecological amplitude and the genetic consequences of small fragmented populations may in part explain the narrow range of local endemics, but that wide outcrossing may provide opportunities for increased genetic variation, increased ecological amplitude and range expansion.
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Affiliation(s)
- B Heliyanto
- School of Plant Biology, Faculty of Natural and Agricultural Sciences, The University of Western Australia, Crawley, WA, Australia
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Playsted CWS, Johnston ME, Ramage CM, Edwards DG, Cawthray GR, Lambers H. Functional significance of dauciform roots: exudation of carboxylates and acid phosphatase under phosphorus deficiency in Caustis blakei (Cyperaceae). New Phytol 2006; 170:491-500. [PMID: 16626471 DOI: 10.1111/j.1469-8137.2006.01697.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2023]
Abstract
Caustis blakei produces an intriguing morphological adaptation by inducing dauciform roots in response to phosphorus (P) deficiency. We tested the hypothesis that these hairy, swollen lateral roots play a similar role to cluster roots in the exudation of organic chelators and ectoenzymes known to aid the chemical mobilization of sparingly available soil nutrients, such as P. Dauciform-root development and exudate composition (carboxylates and acid phosphatase activity) were analysed in C. blakei plants grown in nutrient solution under P-starved conditions. The distribution of dauciform roots in the field was determined in relation to soil profile depth and matrix. The percentage of dauciform roots of the entire root mass was greatest at the lowest P concentration ([P]) in solution, and was suppressed with increasing solution [P], while in the field dauciform roots were predominantely located in the upper soil horizons, and decreased with increasing soil depth. Citrate was the major carboxylate released in an exudative burst from mature dauciform roots, which also produced elevated levels of acid phosphatase activity. Malonate was the dominant internal carboxylate present, with the highest concentration in young dauciform roots. The high concentration of carboxylates and phosphatases released from dauciform roots, combined with their prolific distribution in the organic surface layer of nutrient-impoverished soils, provides an ecophysiological advantage for enhancing nutrient acquisition.
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Affiliation(s)
- Cameron W S Playsted
- School of Agronomy and Horticulture, The University of Queensland, Gatton, Qld 4343, Australia.
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Wouterlood M, Cawthray GR, Scanlon TT, Lambers H, Veneklaas EJ. Carboxylate concentrations in the rhizosphere of lateral roots of chickpea (Cicer arietinum) increase during plant development, but are not correlated with phosphorus status of soil or plants. New Phytol 2004; 162:745-753. [PMID: 33873771 DOI: 10.1111/j.1469-8137.2004.01070.x] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
• The influence of soil P level and plant development on carboxylate concentrations in the rhizosphere of lateral roots of chickpea (Cicer arietinum) cultivars Heera and Tyson were studied to investigate the relationship between carboxylate exudation and P acquisition by chickpea. • Two chickpea cultivars were grown in soil supplied with 0-100 µg P g-1 . Plants were harvested four times during plant development. In two other experiments, carboxylate concentrations were measured along root sections, using plants grown in soil or in hydroponics. • Carboxylate concentrations in the rhizosphere of lateral roots steadily increased with plant development for cv. Heera, but not for Tyson. Carboxylate concentrations increased with increasing distance from the root apex in soil. This increase might be due to accumulation, because an experiment with plants in hydroponics showed that older segments released at least as much carboxylates as younger segments. • Carboxylate concentrations in the rhizosphere of chickpea appear to be developmentally controlled. Unlike some other plant species, there is no simple correlation with plant or soil P status.
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Affiliation(s)
- Madeleine Wouterlood
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Australia
| | - Gregory R Cawthray
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Australia
| | - Timothy T Scanlon
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Australia
| | - Hans Lambers
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Australia
| | - Erik J Veneklaas
- School of Plant Biology, The University of Western Australia, 35 Stirling Highway, Crawley WA 6009, Australia
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Shane MW, Cramer MD, Funayama-Noguchi S, Cawthray GR, Millar AH, Day DA, Lambers H. Developmental physiology of cluster-root carboxylate synthesis and exudation in harsh hakea. Expression of phosphoenolpyruvate carboxylase and the alternative oxidase. Plant Physiol 2004; 135:549-60. [PMID: 15122030 PMCID: PMC429412 DOI: 10.1104/pp.103.035659] [Citation(s) in RCA: 68] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2003] [Revised: 02/16/2004] [Accepted: 02/22/2004] [Indexed: 05/18/2023]
Abstract
Harsh hakea (Hakea prostrata R.Br.) is a member of the Proteaceae family, which is highly represented on the extremely nutrient-impoverished soils in southwest Australia. When phosphorus is limiting, harsh hakea develops proteoid or cluster roots that release carboxylates that mobilize sparingly soluble phosphate in the rhizosphere. To investigate the physiology underlying the synthesis and exudation of carboxylates from cluster roots in Proteaceae, we measured O2 consumption, CO2 release, internal carboxylate concentrations and carboxylate exudation, and the abundance of the enzymes phosphoenolpyruvate carboxylase and alternative oxidase (AOX) over a 3-week time course of cluster-root development. Peak rates of citrate and malate exudation were observed from 12- to 13-d-old cluster roots, preceded by a reduction in cluster-root total protein levels and a reduced rate of O2 consumption. In harsh hakea, phosphoenolpyruvate carboxylase expression was relatively constant in cluster roots, regardless of developmental stage. During cluster-root maturation, however, the expression of AOX protein increased prior to the time when citrate and malate exudation peaked. This increase in AOX protein levels is presumably needed to allow a greater flow of electrons through the mitochondrial electron transport chain in the absence of rapid ATP turnover. Citrate and isocitrate synthesis and accumulation contributed in a major way to the subsequent burst of citrate and malate exudation. Phosphorus accumulated by harsh hakea cluster roots was remobilized during senescence as part of their efficient P cycling strategy for growth on nutrient impoverished soils.
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Affiliation(s)
- Michael W Shane
- School of Plant Biology, Faculty of Natural and Agricultural Sciences, The University of Western Australia, Crawley, Australia.
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Abstract
Reversed-phase column liquid chromatography (RPLC) was used for the separation and quantification of 10 low-molecular-mass organic acids (malic, malonic, lactic, acetic, maleic, citric, cis-aconitic, succinic, fumaric, and trans-aconitic) in plant root exudates. A mobile phase of 93% 25 mM KH2PO4 at pH 2.5 and 7% methanol at a flow-rate of 1 ml min(-1) resolved all 10 acids in 15 min on a C18 column. Experiments demonstrated a significant (P < 0.05) effect of sample pH on detector response, with peak heights being significantly lower at pH 6.0 compared with pH 2.5, but peak area showed no significant difference. At pH 8.0 and above, both peak height and area differed significantly from injections made at pH 2.5. Limits of detection (LOD) for the 10 acids ranged from 0.05 to 24 microM. Finally, the improved method was applied for the analysis of root exudates from soil cultured field pea, Banksia attenuata, white lupin, and chickpea.
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Affiliation(s)
- Gregory R Cawthray
- School of Plant Biology (M090), Faculty of Natural and Agricultural Sciences, The University of Western Australia, 35 Stirling Highway, Crawley, WA 6009, Australia.
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