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Ye W, Di Caprio L, Bruno P, Jaccard C, Bustos-Segura C, Arce CCM, Benrey B. Cultivar-Specific Defense Responses in Wild and Cultivated Squash Induced by Belowground and Aboveground Herbivory. J Chem Ecol 2024:10.1007/s10886-024-01523-9. [PMID: 38914799 DOI: 10.1007/s10886-024-01523-9] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/24/2024] [Revised: 06/08/2024] [Accepted: 06/14/2024] [Indexed: 06/26/2024]
Abstract
Plant domestication often alters plant traits, including chemical and physical defenses against herbivores. In squash, domestication leads to reduced levels of cucurbitacins and leaf trichomes, influencing interactions with insects. However, the impact of domestication on inducible defenses in squash remains poorly understood. Here, we investigated the chemical and physical defensive traits of wild and domesticated squash (Cucurbita argyrosperma), and compared their responses to belowground and aboveground infestation by the root-feeding larvae and the leaf-chewing adults of the banded cucumber beetle Diabrotica balteata (Coleoptera: Chrysomelidae). Wild populations contained cucurbitacins in roots and cotyledons but not in leaves, whereas domesticated varieties lacked cucurbitacins in all tissues. Belowground infestation by D. balteata larvae did not increase cucurbitacin levels in the roots but triggered the expression of cucurbitacin biosynthetic genes, irrespective of domestication status, although the response varied among different varieties. Conversely, whereas wild squash had more leaf trichomes than domesticated varieties, the induction of leaf trichomes in response to herbivory was greater in domesticated plants. Leaf herbivory varied among varieties but there was a trend of higher leaf damage on wild squash than domesticated varieties. Overall, squash plants responded to both belowground and aboveground herbivory by activating chemical defense-associated gene expression in roots and upregulating their physical defense in leaves, respectively. While domestication suppressed both chemical and physical defenses, our findings suggest that it may enhance inducible defense mechanisms by increasing trichome induction in response to herbivory.
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Affiliation(s)
- Wenfeng Ye
- Laboratory of Fundamental and Applied Research in Chemical Ecology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
- CAS Key Laboratory of Insect Developmental and Evolutionary Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institute of Plant Physiology and Ecology, Chinese Academy of Sciences, Shanghai, China
| | - Leandro Di Caprio
- Laboratory of Evolutionary Entomology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
| | - Pamela Bruno
- Laboratory of Fundamental and Applied Research in Chemical Ecology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
- Plant Production Systems, Route Des Eterpys 18, 1964, Agroscope, Conthey, Switzerland
| | - Charlyne Jaccard
- Laboratory of Evolutionary Entomology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
| | - Carlos Bustos-Segura
- Laboratory of Evolutionary Entomology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
- Sensory Ecology, Institute of Ecology and Environmental Sciences of Paris, INRAE, Versailles, France
| | - Carla C M Arce
- Laboratory of Fundamental and Applied Research in Chemical Ecology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
| | - Betty Benrey
- Laboratory of Evolutionary Entomology, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland.
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2
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Thorne SJ, Maathuis FJM, Hartley SE. Induction of silicon defences in wheat landraces is local, not systemic, and driven by mobilization of soluble silicon to damaged leaves. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:5363-5373. [PMID: 37314063 DOI: 10.1093/jxb/erad224] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2023] [Accepted: 06/13/2023] [Indexed: 06/15/2023]
Abstract
In response to herbivory, many grasses, including crops such as wheat, accumulate significant levels of silicon (Si) as an antiherbivore defence. Damage-induced increases in Si can be localized in damaged leaves or be more systemic, but the mechanisms leading to these differences in Si distribution remain untested. Ten genetically diverse wheat landraces (Triticum aestivum) were used to assess genotypic variation in Si induction in response to mechanical damage and how this was affected by exogenous Si supply. Total and soluble Si levels were measured in damaged and undamaged leaves as well as in the phloem to test how Si was allocated to different parts of the plant after damage. Localized, but not systemic, induction of Si defences occurred, and was more pronounced when plants had supplemental Si. Damaged plants had significant increases in Si concentration in their damaged leaves, while the Si concentration in undamaged leaves decreased, such that there was no difference in the average Si concentration of damaged and undamaged plants. The increased Si in damaged leaves was due to the redirection of soluble Si, present in the phloem, from undamaged to damaged plant parts, potentially a more cost-effective defence mechanism for plants than increased Si uptake.
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Affiliation(s)
- Sarah J Thorne
- Plants, Photosynthesis, and Soil, School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK
| | | | - Susan E Hartley
- Plants, Photosynthesis, and Soil, School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK
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3
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de Tombeur F, Raven JA, Toussaint A, Lambers H, Cooke J, Hartley SE, Johnson SN, Coq S, Katz O, Schaller J, Violle C. Why do plants silicify? Trends Ecol Evol 2023; 38:275-288. [PMID: 36428125 DOI: 10.1016/j.tree.2022.11.002] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2022] [Revised: 10/30/2022] [Accepted: 11/02/2022] [Indexed: 11/24/2022]
Abstract
Despite seminal papers that stress the significance of silicon (Si) in plant biology and ecology, most studies focus on manipulations of Si supply and mitigation of stresses. The ecological significance of Si varies with different levels of biological organization, and remains hard to capture. We show that the costs of Si accumulation are greater than is currently acknowledged, and discuss potential links between Si and fitness components (growth, survival, reproduction), environment, and ecosystem functioning. We suggest that Si is more important in trait-based ecology than is currently recognized. Si potentially plays a significant role in many aspects of plant ecology, but knowledge gaps prevent us from understanding its possible contribution to the success of some clades and the expansion of specific biomes.
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Affiliation(s)
- Félix de Tombeur
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France; School of Biological Sciences and Institute of Agriculture, The University of Western Australia, Perth, Australia.
| | - John A Raven
- Division of Plant Science, University of Dundee at the James Hutton Institute, Invergowrie, UK; School of Biological Sciences, The University of Western Australia, Perth, Australia; Climate Change Cluster, Faculty of Science, University of Technology Sydney, Ultimo, Australia
| | - Aurèle Toussaint
- Department of Botany, Institute of Ecology and Earth Sciences, University of Tartu, Tartu, Estonia
| | - Hans Lambers
- School of Biological Sciences and Institute of Agriculture, The University of Western Australia, Perth, Australia
| | - Julia Cooke
- School of Environment, Earth and Ecosystem Sciences, The Open University, Milton Keynes, UK
| | - Sue E Hartley
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, UK
| | - Scott N Johnson
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, Australia
| | - Sylvain Coq
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
| | - Ofir Katz
- Dead Sea and Arava Science Center, Mount Masada, Tamar Regional Council, Israel; Eilat Campus, Ben-Gurion University of the Negev, Eilat, Israel
| | - Jörg Schaller
- Leibniz Centre for Agricultural Landscape Research (ZALF), Müncheberg, Germany
| | - Cyrille Violle
- CEFE, Univ Montpellier, CNRS, EPHE, IRD, Montpellier, France
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4
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Tamrat S, Borrell JS, Shiferaw E, Wondimu T, Kallow S, Davies RM, Dickie JB, Nuraga GW, White O, Woldeyes F, Demissew S, Wilkin P. Reproductive biology of wild and domesticated Ensete ventricosum: Further evidence for maintenance of sexual reproductive capacity in a vegetatively propagated perennial crop. PLANT BIOLOGY (STUTTGART, GERMANY) 2022; 24:482-491. [PMID: 35137516 PMCID: PMC9303740 DOI: 10.1111/plb.13390] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Accepted: 12/22/2021] [Indexed: 06/14/2023]
Abstract
Loss of sexual reproductive capacity has been proposed as a syndrome of domestication in vegetatively propagated crops, but there are relatively few examples from agricultural systems. In this study, we compare sexual reproductive capacity in wild (sexual) and domesticated (vegetative) populations of enset (Ensete ventricosum (Welw.) Cheesman), a tropical banana relative and Ethiopian food security crop. We examined floral and seed morphology and germination ecology across 35 wild and domesticated enset. We surveyed variation in floral and seed traits, including seed weight, viability and internal morphology, and germinated seeds across a range of constant and alternating temperature regimes to characterize optimum germination requirements. We report highly consistent floral allometry, seed viability, internal morphology and days to germination in wild and domesticated enset. However, seeds from domesticated plants responded to cooler temperatures with greater diurnal range. Shifts in germination behaviour appear concordant with a climatic envelope shift in the domesticated distribution. Our findings provide evidence that sexual reproductive capacity has been maintained despite long-term near-exclusive vegetative propagation in domesticated enset. Furthermore, certain traits such as germination behaviour and floral morphology may be under continued selection, presumably through rare sexually reproductive events. Compared to sexually propagated crops banked as seeds, vegetative crop diversity is typically conserved in living collections that are more costly and insecure. Improved understanding of sexual propagation in vegetative crops may have applications in germplasm conservation and plant breeding.
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Affiliation(s)
- S. Tamrat
- Department of Plant Biology and Biodiversity ManagementAddis Ababa UniversityAddis AbabaEthiopia
- Department of BiologyDilla UniversityDillaSouthern Ethiopia
| | | | - E. Shiferaw
- Ethiopian Biodiversity InstituteAddis AbabaEthiopia
| | - T. Wondimu
- Department of Plant Biology and Biodiversity ManagementAddis Ababa UniversityAddis AbabaEthiopia
| | - S. Kallow
- Royal Botanic Gardens KewMillennium Seed BankWakehurst, ArdinglySussexUK
- Department of BiosystemsKatholieke Universiteit LeuvenLeuvenBelgium
| | - R. M. Davies
- Royal Botanic Gardens KewMillennium Seed BankWakehurst, ArdinglySussexUK
| | - J. B. Dickie
- Royal Botanic Gardens KewMillennium Seed BankWakehurst, ArdinglySussexUK
| | - G. W. Nuraga
- Department of Plant Biology and Biodiversity ManagementAddis Ababa UniversityAddis AbabaEthiopia
| | - O. White
- Royal Botanic GardensKew, RichmondSurreyUK
| | - F. Woldeyes
- Ethiopian Biodiversity InstituteAddis AbabaEthiopia
| | - S. Demissew
- Department of Plant Biology and Biodiversity ManagementAddis Ababa UniversityAddis AbabaEthiopia
| | - P. Wilkin
- Royal Botanic GardensKew, RichmondSurreyUK
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5
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Johnson SN, Cibils-Stewart X, Waterman JM, Biru FN, Rowe RC, Hartley SE. Elevated atmospheric CO 2 changes defence allocation in wheat but herbivore resistance persists. Proc Biol Sci 2022; 289:20212536. [PMID: 35168395 PMCID: PMC8848237 DOI: 10.1098/rspb.2021.2536] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/23/2021] [Accepted: 01/14/2022] [Indexed: 11/12/2022] Open
Abstract
Predicting how plants allocate to different anti-herbivore defences in response to elevated carbon dioxide (CO2) concentrations is important for understanding future patterns of crop susceptibility to herbivory. Theories of defence allocation, especially in the context of environmental change, largely overlook the role of silicon (Si), despite it being the major anti-herbivore defence in the Poaceae. We demonstrated that elevated levels of atmospheric CO2 (e[CO2]) promoted plant growth by 33% and caused wheat (Triticum aestivum) to switch from Si (-19%) to phenolic (+44%) defences. Despite the lower levels of Si under e[CO2], resistance to the global pest Helicoverpa armigera persisted; relative growth rates (RGRs) were reduced by at least 33% on Si-supplied plants, irrespective of CO2 levels. RGR was negatively correlated with leaf Si concentrations. Mandible wear was c. 30% higher when feeding on Si-supplemented plants compared to those feeding on plants with no Si supply. We conclude that higher carbon availability under e[CO2] reduces silicification and causes wheat to increase concentrations of phenolics. However, Si supply, at all levels, suppressed the growth of H. armigera under both CO2 regimes, suggesting that shifts in defence allocation under future climate change may not compromise herbivore resistance in wheat.
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Affiliation(s)
- Scott N. Johnson
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Ximena Cibils-Stewart
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
- Instituto Nacional de Investigación Agropecuaria (INIA), La Estanzuela Research Station, Ruta 50, Km. 11, Colonia, Uruguay
| | - Jamie M. Waterman
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Fikadu N. Biru
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
- College of Agriculture and Veterinary Medicine, Jimma University, Jimma 307, Ethiopia
| | - Rhiannon C. Rowe
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Susan E. Hartley
- School of Biosciences, University of Sheffield, Sheffield S10 2TN, UK
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6
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Thorne SJ, Stirnberg PM, Hartley SE, Maathuis FJM. The Ability of Silicon Fertilisation to Alleviate Salinity Stress in Rice is Critically Dependent on Cultivar. RICE (NEW YORK, N.Y.) 2022; 15:8. [PMID: 35112196 PMCID: PMC8810965 DOI: 10.1186/s12284-022-00555-7] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/01/2021] [Accepted: 01/19/2022] [Indexed: 06/14/2023]
Abstract
Silicon (Si) fertiliser can improve rice (Oryza sativa) tolerance to salinity. The rate of Si uptake and its associated benefits are known to differ between plant genotypes, but, to date, little research has been done on how the benefits, and hence the economic feasibility, of Si fertilisation varies between cultivars. In this study, a range of rice cultivars was grown both hydroponically and in soil, at different levels of Si and NaCl, to determine cultivar variation in the response to Si. There was significant variation in the effect of Si, such that Si alleviated salt-induced growth inhibition in some cultivars, while others were unaffected, or even negatively impacted. Thus, when assessing the benefits of Si supplementation in alleviating salt stress, it is essential to collect cultivar-specific data, including yield, since changes in biomass were not always correlated with those seen for yield. Root Si content was found to be more important than shoot Si in protecting rice against salinity stress, with a root Si level of 0.5-0.9% determined as having maximum stress alleviation by Si. A cost-benefit analysis indicated that Si fertilisation is beneficial in mild stress, high-yield conditions but is not cost-effective in low-yield production systems.
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Affiliation(s)
- Sarah J Thorne
- Department of Biology, University of York, York, YO10 5DD, UK
| | | | - Susan E Hartley
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield, S10 2TN, UK
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7
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Gómez-Fernández A, Osborne CP, Rees M, Palomino J, Ingala C, Gómez G, Milla R. Disparities among crop species in the evolution of growth rates: the role of distinct origins and domestication histories. THE NEW PHYTOLOGIST 2022; 233:995-1010. [PMID: 34726792 DOI: 10.1111/nph.17840] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/30/2021] [Accepted: 10/24/2021] [Indexed: 06/13/2023]
Abstract
Growth rates vary widely among plants with different strategies. For crops, evolution under predictable and high-resource environments might favour rapid resource acquisition and growth, but whether this strategy has consistently evolved during domestication and improvement remains unclear. Here we report a comprehensive study of the evolution of growth rates based on comparisons among wild, landrace, and improved accessions of 19 herbaceous crops grown under common conditions. We also examined the underlying growth components and the influence of crop origin and history on growth evolution. Domestication and improvement did not affect growth consistently, that is growth rates increased or decreased or remained unchanged in different crops. Crops selected for fruits increased the physiological component of growth (net assimilation rate), whereas leaf and seed crops showed larger domestication effects on morphology (leaf mass ratio and specific leaf area). Moreover, climate and phylogeny contributed to explaining the effects of domestication and changes in growth. Crop-specific responses to domestication and improvement suggest that selection for high yield has not consistently changed growth rates. The trade-offs between morpho-physiological traits and the distinct origins and histories of crops accounted for the variability in growth changes. These findings have far-reaching implications for our understanding of crop performance and adaptation.
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Affiliation(s)
- Alicia Gómez-Fernández
- Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, C/Tulipán s/n, Móstoles, 28933, Spain
| | - Colin P Osborne
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Mark Rees
- Plants, Photosynthesis and Soil, School of Biosciences, University of Sheffield, Sheffield, S10 2TN, UK
| | - Javier Palomino
- Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, C/Tulipán s/n, Móstoles, 28933, Spain
| | - Carlos Ingala
- Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, C/Tulipán s/n, Móstoles, 28933, Spain
| | - Guillermo Gómez
- Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, C/Tulipán s/n, Móstoles, 28933, Spain
| | - Rubén Milla
- Departamento de Biología y Geología, Física y Química Inorgánica, Universidad Rey Juan Carlos, C/Tulipán s/n, Móstoles, 28933, Spain
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8
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de Tombeur F, Cornelis JT, Lambers H. Silicon mobilisation by root-released carboxylates. TRENDS IN PLANT SCIENCE 2021; 26:1116-1125. [PMID: 34315662 DOI: 10.1016/j.tplants.2021.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/12/2021] [Revised: 06/30/2021] [Accepted: 07/01/2021] [Indexed: 06/13/2023]
Abstract
Plants have evolved numerous strategies to acquire poorly available nutrients from soil, including the release of carboxylates from their roots. Silicon (Si) release from mineral dissolution increases in the presence of chelating substances, and recent evidence shows that leaf [Si] increases markedly in old phosphorus (P)-depleted soils, where many species exhibit carboxylate-releasing strategies, compared with younger P-richer soils. Here, we propose that root-released carboxylates, and more generally rhizosphere processes, play an overlooked role in plant Si accumulation by increasing soil Si mobilisation from minerals. We suggest that Si mobilisation is costly in terms of carbon but becomes cheaper if those costs are already met to acquire poorly available P. Uptake of the mobilised Si by roots will then depend on whether they express Si transporters.
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Affiliation(s)
- Félix de Tombeur
- TERRA Teaching and Research Centre, Gembloux Agro-Bio Tech, University of Liege, Gembloux, Belgium.
| | - Jean-Thomas Cornelis
- TERRA Teaching and Research Centre, Gembloux Agro-Bio Tech, University of Liege, Gembloux, Belgium; Faculty of Land and Food Systems, The University of British Columbia, Vancouver, BC, V6T 1Z4, Canada
| | - Hans Lambers
- School of Biological Sciences, The University of Western Australia, Crawley (Perth), WA 6009, Australia.
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9
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Waterman JM, Cibils-Stewart X, Cazzonelli CI, Hartley SE, Johnson SN. Short-term exposure to silicon rapidly enhances plant resistance to herbivory. Ecology 2021; 102:e03438. [PMID: 34139023 DOI: 10.1002/ecy.3438] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/25/2021] [Revised: 04/29/2021] [Accepted: 05/25/2021] [Indexed: 01/17/2023]
Abstract
Silicon (Si) can adversely affect insect herbivores, particularly in plants that evolved the ability to accumulate large quantities of Si. Very rapid herbivore-induced accumulation of Si has recently been demonstrated, but the level of protection against herbivory this affords plants remains unknown. Brachypodium distachyon, a model Si hyperaccumulating grass, was exposed to the chewing herbivore, Helicoverpa armigera, and grown under three conditions: supplied Si over 34 d (+Si), not supplied Si (-Si), or supplied Si once herbivory began (-Si → +Si). We evaluated the effectiveness of each Si treatment at reducing herbivore performance and measured Si-based defenses and phenolics (another form of defense often reduced by Si). Although Si concentrations remained lower, within 72 h of exposure to Si, -Si → +Si plants were as resistant to herbivory as +Si plants. Both +Si and -Si → +Si treatments reduced herbivore damage and growth, and increased mandible wear compared to -Si. After 6 h, herbivory increased filled Si cell density in -Si → +Si plants, and within 24 h, -Si → +Si plants reached similar filled Si cell densities to +Si plants, although decreased phenolics only occurred in +Si plants. We demonstrate that plants with short-term Si exposure can rapidly accumulate Si-based antiherbivore defenses as effectively as plants with long-term exposure.
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Affiliation(s)
- Jamie M Waterman
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia
| | - Ximena Cibils-Stewart
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia.,Instituto Nacional de Investigación Agropecuaria (INIA), La Estanzuela Research Station, Ruta 50, Km. 11, Colonia, Uruguay
| | - Christopher I Cazzonelli
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia
| | - Susan E Hartley
- Department of Animal and Plant Sciences, University of Sheffield, Western Bank, Sheffield, S10 2TN, UK
| | - Scott N Johnson
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, New South Wales, 2751, Australia
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10
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Simpson KJ, Atkinson RRL, Mockford EJ, Bennett C, Osborne CP, Rees M. Large seeds provide an intrinsic growth advantage that depends on leaf traits and root allocation. Funct Ecol 2021. [DOI: 10.1111/1365-2435.13871] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Affiliation(s)
| | | | - Emily J. Mockford
- Department of Animal and Plant Sciences University of Sheffield Sheffield UK
| | - Christopher Bennett
- Department of Animal and Plant Sciences University of Sheffield Sheffield UK
| | - Colin P. Osborne
- Department of Animal and Plant Sciences University of Sheffield Sheffield UK
| | - Mark Rees
- Department of Animal and Plant Sciences University of Sheffield Sheffield UK
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11
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Thorne SJ, Hartley SE, Maathuis FJM. The Effect of Silicon on Osmotic and Drought Stress Tolerance in Wheat Landraces. PLANTS (BASEL, SWITZERLAND) 2021; 10:814. [PMID: 33924159 PMCID: PMC8074377 DOI: 10.3390/plants10040814] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 03/25/2021] [Revised: 04/16/2021] [Accepted: 04/19/2021] [Indexed: 12/13/2022]
Abstract
Drought stress reduces annual global wheat yields by 20%. Silicon (Si) fertilisation has been proposed to improve plant drought stress tolerance. However, it is currently unknown if and how Si affects different wheat landraces, especially with respect to their innate Si accumulation properties. In this study, significant and consistent differences in Si accumulation between landraces were identified, allowing for the classification of high Si accumulators and low Si accumulators. Landraces from the two accumulation groups were then used to investigate the effect of Si during osmotic and drought stress. Si was found to improve growth marginally in high Si accumulators during osmotic stress. However, no significant effect of Si on growth during drought stress was found. It was further found that osmotic stress decreased Si accumulation for all landraces whereas drought increased it. Overall, these results suggest that the beneficial effect of Si commonly reported in similar studies is not universal and that the application of Si fertiliser as a solution to agricultural drought stress requires detailed understanding of genotype-specific responses to Si.
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Affiliation(s)
- Sarah J. Thorne
- Department of Biology, University of York, York YO10 5DD, UK;
| | - Susan E. Hartley
- Department of Animal and Plant Sciences, University of Sheffield, Sheffield S10 2TN, UK;
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12
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Cowan MF, Blomstedt CK, Møller BL, Henry RJ, Gleadow RM. Variation in production of cyanogenic glucosides during early plant development: A comparison of wild and domesticated sorghum. PHYTOCHEMISTRY 2021; 184:112645. [PMID: 33482417 DOI: 10.1016/j.phytochem.2020.112645] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2020] [Revised: 12/21/2020] [Accepted: 12/22/2020] [Indexed: 06/12/2023]
Abstract
Domestication has narrowed the genetic diversity found in crop wild relatives, potentially reducing plasticity to cope with a changing climate. The tissues of domesticated sorghum (Sorghum bicolor), especially in younger plants, are cyanogenic and potentially toxic. Species of wild sorghum produce lower levels of the cyanogenic glucoside (CNglc) dhurrin than S. bicolor at maturity, but it is not known if this is also the case during germination and early growth. CNglcs play multiple roles in primary and specialised metabolism in domesticated sorghum and other crop plants. In this study, the temporal and spatial distribution of dhurrin in wild and domesticated sorghum at different growth stages was monitored in leaf, sheath and root tissues up to 35 days post germination using S. bicolor and the wild species S. brachypodum and S. macrospermum as the experimental systems. Growth parameters were also measured and allocation of plant total nitrogen (N%) to both dhurrin and nitrate (NO3-) was calculated. Negligible amounts of dhurrin were produced in the leaves of the two wild species compared to S. bicolor. The morphology of the two wild sorghums also differed from S. bicolor, with the greatest differences observed for the more distantly related S. brachypodum. S. bicolor had the highest leaf N% whilst the wild species had significantly higher root N%. Allocation of nitrogen to dhurrin in aboveground tissue was significantly higher in S. bicolor compared to the wild species but did not differ in the roots across the three species. The differences in plant morphology, dhurrin content and re-mobilisation, and nitrate/nitrogen allocation suggest that domestication has affected the functional roles of dhurrin in sorghum.
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Affiliation(s)
- Max F Cowan
- School of Biological Sciences, Monash University, Wellington Rd, Clayton, Victoria, 3800, Australia
| | - Cecilia K Blomstedt
- School of Biological Sciences, Monash University, Wellington Rd, Clayton, Victoria, 3800, Australia
| | - Birger Lindberg Møller
- Plant Biochemistry Laboratory, Department of Plant and Environmental Sciences, University of Copenhagen, 40 Thorvaldsensvej, DK-1871, Frederiksberg C, Copenhagen, Denmark; VILLUM Research Center Plant Plasticity, University of Copenhagen, 40 Thorvaldsensvej, DK-1871, Frederiksberg C, Copenhagen, Denmark
| | - Robert J Henry
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD, 4072, Australia
| | - Roslyn M Gleadow
- School of Biological Sciences, Monash University, Wellington Rd, Clayton, Victoria, 3800, Australia; Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St Lucia, QLD, 4072, Australia.
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13
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Tombeur F, Laliberté E, Lambers H, Faucon M, Zemunik G, Turner BL, Cornelis J, Mahy G. A shift from phenol to silica‐based leaf defences during long‐term soil and ecosystem development. Ecol Lett 2021; 24:984-995. [DOI: 10.1111/ele.13713] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2020] [Revised: 01/07/2021] [Accepted: 02/06/2021] [Indexed: 01/02/2023]
Affiliation(s)
- Felix Tombeur
- TERRA Teaching and Research Centre Gembloux Agro‐Bio Tech University of Liege Gembloux Belgium
| | - Etienne Laliberté
- Institut de Recherche en Biologie Végétale Université de Montréal 4101 Sherbrooke Est Montréal QC H1X 2B2 Canada
- School of Biological Sciences The University of Western Australia Crawley (Perth) WA 6009 Australia
| | - Hans Lambers
- School of Biological Sciences The University of Western Australia Crawley (Perth) WA 6009 Australia
| | - Michel‐Pierre Faucon
- AGHYLE SFR Condorcet FR CNRS 3417 UniLaSalle 19 rue Pierre Waguet Beauvais 60026 France
| | - Graham Zemunik
- School of Biological Sciences The University of Western Australia Crawley (Perth) WA 6009 Australia
| | - Benjamin L. Turner
- Smithsonian Tropical Research Institute Apartado 0843‐03092 Balboa Ancon Panama
- Soil and Water Science Department University of Florida Gainesville FL 32611 USA
| | - Jean‐Thomas Cornelis
- TERRA Teaching and Research Centre Gembloux Agro‐Bio Tech University of Liege Gembloux Belgium
- Faculty of Land and Food Systems The University of British Columbia Vancouver BC V6T 1Z4 Canada
| | - Grégory Mahy
- TERRA Teaching and Research Centre Gembloux Agro‐Bio Tech University of Liege Gembloux Belgium
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14
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Myrans H, Vandegeer RK, Henry RJ, Gleadow RM. Nitrogen availability and allocation in sorghum and its wild relatives: Divergent roles for cyanogenic glucosides. JOURNAL OF PLANT PHYSIOLOGY 2021; 258-259:153393. [PMID: 33667954 DOI: 10.1016/j.jplph.2021.153393] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2020] [Revised: 02/15/2021] [Accepted: 02/16/2021] [Indexed: 06/12/2023]
Abstract
Crop plants are assumed to have become more susceptible to pests as a result of selection for high growth rates during the process of domestication, consistent with resource allocation theories. We compared the investment by domesticated sorghum into cyanogenic glucosides, nitrogen-based specialised metabolites that break down to release hydrogen cyanide, with five wild relatives native to Australia. Plants were grown in pots in a greenhouse and supplied with low and high concentrations of nitrogen and monitored for 9 weeks. The concentrations of nitrate, total phenolics and silicon were also measured. Domesticated Sorghum bicolor had the highest leaf and root cyanogenic glucoside concentrations, and among the lowest nitrate and silicon concentrations under both treatments. Despite partitioning a much higher proportion of its stored nitrogen to cyanogenic glucosides than the wild species, S. bicolor's nitrogen productivity levels were among the highest. Most of the wild sorghums had higher concentrations of silicon and phenolics, which may provide an alternative defence system. Cyanogenic glucosides appear to be integral to S. bicolor's physiology, having roles in both growth and defence. Sorghum macrospermum displayed consistently low cyanogenic glucoside concentrations, high growth rates and high nitrogen productivity and represents a particularly attractive genetic resource for sorghum improvement.
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Affiliation(s)
- Harry Myrans
- School of Biological Sciences, Monash University, Wellington Rd, Clayton, VIC 3800, Australia
| | - Rebecca K Vandegeer
- Hawkesbury Institute for the Environment, Western Sydney University, Locked Bag 1797, Penrith, NSW 2751, Australia
| | - Robert J Henry
- Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, 4072, Australia
| | - Roslyn M Gleadow
- School of Biological Sciences, Monash University, Wellington Rd, Clayton, VIC 3800, Australia; Queensland Alliance for Agriculture and Food Innovation, The University of Queensland, St. Lucia, QLD, 4072, Australia.
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15
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Soltani A, Walter KA, Wiersma AT, Santiago JP, Quiqley M, Chitwood D, Porch TG, Miklas P, McClean PE, Osorno JM, Lowry DB. The genetics and physiology of seed dormancy, a crucial trait in common bean domestication. BMC PLANT BIOLOGY 2021; 21:58. [PMID: 33482732 PMCID: PMC7821524 DOI: 10.1186/s12870-021-02837-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/02/2020] [Accepted: 01/11/2021] [Indexed: 05/21/2023]
Abstract
BACKGROUND Physical seed dormancy is an important trait in legume domestication. Although seed dormancy is beneficial in wild ecosystems, it is generally considered to be an undesirable trait in crops due to reduction in yield and / or quality. The physiological mechanism and underlying genetic factor(s) of seed dormancy is largely unknown in several legume species. Here we employed an integrative approach to understand the mechanisms controlling physical seed dormancy in common bean (Phaseolus vulgaris L.). RESULTS Using an innovative CT scan imaging system, we were able to track water movements inside the seed coat. We found that water uptake initiates from the bean seed lens. Using a scanning electron microscopy (SEM) we further identified several micro-cracks on the lens surface of non-dormant bean genotypes. Bulked segregant analysis (BSA) was conducted on a bi-parental RIL (recombinant inbred line) population, segregating for seed dormancy. This analysis revealed that the seed water uptake is associated with a single major QTL on Pv03. The QTL region was fine-mapped to a 118 Kb interval possessing 11 genes. Coding sequence analysis of candidate genes revealed a 5-bp insertion in an ortholog of pectin acetylesterase 8 that causes a frame shift, loss-of-function mutation in non-dormant genotype. Gene expression analysis of the candidate genes in the seed coat of contrasting genotypes indicated 21-fold lower expression of pectin acetylesterase 8 in non-dormant genotype. An analysis of mutational polymorphism was conducted among wild and domesticated beans. Although all the wild beans possessed the functional allele of pectin acetylesterase 8, the majority (77%) of domesticated beans had the non-functional allele suggesting that this variant was under strong selection pressure through domestication. CONCLUSIONS In this study, we identified the physiological mechanism of physical seed dormancy and have identified a candidate allele causing variation in this trait. Our findings suggest that a 5-bp insertion in an ortholog of pectin acetylesterase 8 is likely a major causative mutation underlying the loss of seed dormancy during domestication. Although the results of current study provide strong evidences for the role of pectin acetylesterase 8 in seed dormancy, further confirmations seem necessary by employing transgenic approaches.
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Affiliation(s)
- Ali Soltani
- Plant Resilience Institute, Michigan State University, East Lansing, MI, USA.
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA.
| | - Katelynn A Walter
- Plant Resilience Institute, Michigan State University, East Lansing, MI, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA
| | - Andrew T Wiersma
- Department of Plant, Soil and Microbial Sciences, Michigan State University, East Lansing, MI, USA
| | - James P Santiago
- Plant Resilience Institute, Michigan State University, East Lansing, MI, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA
| | - Michelle Quiqley
- Department of Horticulture, Michigan State University, East Lansing, MI, USA
- Department of Computational Mathematics, Science and Engineering, Michigan State University, East Lansing, MI, USA
| | - Daniel Chitwood
- Department of Horticulture, Michigan State University, East Lansing, MI, USA
- Department of Computational Mathematics, Science and Engineering, Michigan State University, East Lansing, MI, USA
| | - Timothy G Porch
- USDA-ARS, Tropical Agriculture Research Station, Mayaguez, PR, USA
| | - Phillip Miklas
- USDA-ARS, Grain Legume Genetics Physiology Research Unit, Prosser, WA, USA
| | - Phillip E McClean
- Department of Plant Sciences, North Dakota State University, Fargo, ND, USA
| | - Juan M Osorno
- Department of Plant Sciences, North Dakota State University, Fargo, ND, USA
| | - David B Lowry
- Plant Resilience Institute, Michigan State University, East Lansing, MI, USA
- Department of Plant Biology, Michigan State University, East Lansing, MI, USA
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16
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Hall CR, Mikhael M, Hartley SE, Johnson SN. Elevated atmospheric CO
2
suppresses jasmonate and silicon‐based defences without affecting herbivores. Funct Ecol 2020. [DOI: 10.1111/1365-2435.13549] [Citation(s) in RCA: 28] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
Affiliation(s)
- Casey R. Hall
- Hawkesbury Institute for the Environment Western Sydney University Richmond NSW Australia
| | - Meena Mikhael
- School of Medicine Western Sydney University Campbelltown NSW Australia
| | - Susan E. Hartley
- Department of Animal and Plant Sciences University of Sheffield Sheffield UK
| | - Scott N. Johnson
- Hawkesbury Institute for the Environment Western Sydney University Richmond NSW Australia
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17
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Preece C, Peñuelas J. A Return to the Wild: Root Exudates and Food Security. TRENDS IN PLANT SCIENCE 2020; 25:14-21. [PMID: 31648938 DOI: 10.1016/j.tplants.2019.09.010] [Citation(s) in RCA: 57] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/15/2019] [Revised: 09/21/2019] [Accepted: 09/30/2019] [Indexed: 05/07/2023]
Abstract
Challenges to food security under conditions of global change are forcing us to increase global crop production. Focussing on belowground plant traits, especially root exudation, has great promise to meet this challenge. Root exudation is the release of a vast array of compounds into the soil. These exudates are involved in many biotic and abiotic interactions. Wild relatives of crops provide a large potential source of information and genetic material and have desirable traits that could be incorporated into modern breeding programs. However, root exudates are currently underexploited. Here, we highlight how the traits of root exudates of crop wild relatives could be used to improve agricultural output and reduce environmental impacts, particularly by decreasing our dependence on pesticides and fertilisers.
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Affiliation(s)
- Catherine Preece
- CREAF, Cerdanyola del Vallès, 08193, Catalonia, Spain; CSIC, Global Ecology Unit CREAF-CSIC-UAB, Bellaterra 08193, Catalonia, Spain.
| | - Josep Peñuelas
- CREAF, Cerdanyola del Vallès, 08193, Catalonia, Spain; CSIC, Global Ecology Unit CREAF-CSIC-UAB, Bellaterra 08193, Catalonia, Spain
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18
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Whitehead SR, Poveda K. Resource allocation trade-offs and the loss of chemical defences during apple domestication. ANNALS OF BOTANY 2019; 123:1029-1041. [PMID: 30770925 PMCID: PMC6589505 DOI: 10.1093/aob/mcz010] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2018] [Accepted: 01/17/2019] [Indexed: 05/23/2023]
Abstract
BACKGROUND AND AIMS Most crops have been dramatically altered from their wild ancestors with the primary goal of increasing harvestable yield. A long-held hypothesis is that increased allocation to yield has reduced plant investment in defence and resulted in crops that are highly susceptible to pests. However, clear demonstrations of these trade-offs have been elusive due to the many selective pressures that occur concurrently during crop domestication. METHODS To provide a robust test of whether increased allocation to yield can alter plant investment in defence, this study examined fruit chemical defence traits and herbivore resistance across 52 wild and 56 domesticated genotypes of apples that vary >26-fold in fruit size. Ninety-six phenolic metabolites were quantified in apple skin, pulp and seeds, and resistance to the codling moth was assessed with a series of bioassays. KEY RESULTS The results show that wild apples have higher total phenolic concentrations and a higher diversity of metabolites than domesticated apples in skin, pulp and seeds. A negative phenotypic relationship between fruit size and phenolics indicates that this pattern is driven in part by allocation-based trade-offs between yield and defence. There were no clear differences in codling moth performance between wild and domesticated apples and no overall effects of total phenolic concentration on codling moth performance, but the results did show that codling moth resistance was increased in apples with higher phenolic diversity. The concentrations of a few individual compounds (primarily flavan-3-ols) also correlated with increased resistance, primarily driven by a reduction in pupal mass of female moths. CONCLUSIONS The negative phenotypic relationship between fruit size and phenolic content, observed across a large number of wild and domesticated genotypes, supports the hypothesis of yield-defence trade-offs in crops. However, the limited effects of phenolics on codling moth highlight the complexity of consequences that domestication has for plant-herbivore interactions. Continued studies of crop domestication can further our understanding of the multiple trade-offs involved in plant defence, while simultaneously leading to novel discoveries that can improve the sustainability of crop production.
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Affiliation(s)
- Susan R Whitehead
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, USA
- Department of Entomology, Cornell University, Ithaca, USA
| | - Katja Poveda
- Department of Entomology, Cornell University, Ithaca, USA
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19
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Wilkinson TDJ, Ferrari J, Hartley SE, Hodge A. Aphids can acquire the nitrogen delivered to plants by arbuscular mycorrhizal fungi. Funct Ecol 2019. [DOI: 10.1111/1365-2435.13283] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Affiliation(s)
| | | | - Sue E. Hartley
- Department of Biology University of York York UK
- York Environmental Sustainability Institute University of York York UK
| | - Angela Hodge
- Department of Biology University of York York UK
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20
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Johnson SN, Hartley SE. Elevated carbon dioxide and warming impact silicon and phenolic-based defences differently in native and exotic grasses. GLOBAL CHANGE BIOLOGY 2018; 24:3886-3896. [PMID: 29105229 DOI: 10.1111/gcb.13971] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 10/12/2017] [Indexed: 05/22/2023]
Abstract
Global climate change may increase invasions of exotic plant species by directly promoting the success of invasive/exotic species or by reducing the competitive abilities of native species. Changes in plant chemistry, leading to altered susceptibility to stress, could mediate these effects. Grasses are hyper-accumulators of silicon, which play a crucial function in the alleviation of diverse biotic and abiotic stresses. It is unknown how predicted increases in atmospheric carbon dioxide (CO2 ) and air temperature affect silicon accumulation in grasses, especially in relation to primary and secondary metabolites. We tested how elevated CO2 (eCO2 ) (+240 ppm) and temperature (eT) (+4°C) affected chemical composition (silicon, phenolics, carbon and nitrogen) and plant growth in eight grass species, either native or exotic to Australia. eCO2 increased phenolic concentrations by 11%, but caused silicon accumulation to decline by 12%. Moreover, declines in silicon occurred mainly in native species (-19%), but remained largely unchanged in exotic species. Conversely, eT increased silicon accumulation in native species (+19%) but decreased silicon accumulation in exotic species (-10%). Silicon and phenolic concentrations were negatively correlated with each other, potentially reflecting a defensive trade-off. Moreover, both defences were negatively correlated with plant mass, compatible with a growth-defence trade-off. Grasses responded in a species-specific manner, suggesting that the relative susceptibility of different species may differ under future climates compared to current species rankings of resource quality. For example, the native Microlaena stipoides was less well defended under eCO2 in terms of both phenolics and silicon, and thus could suffer greater vulnerability to herbivores. To our knowledge, this is the first demonstration of the impacts of eCO2 and eT on silicon accumulation in grasses. We speculate that the greater plasticity in silicon uptake shown by Australian native grasses may be partly a consequence of evolving in a low nutrient and seasonally arid environment.
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Affiliation(s)
- Scott N Johnson
- Hawkesbury Institute for the Environment, Western Sydney University, Penrith, NSW, Australia
| | - Susan E Hartley
- Department of Biology, York Environment and Sustainability Institute, University of York, York, UK
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21
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Frew A, Weston LA, Reynolds OL, Gurr GM. The role of silicon in plant biology: a paradigm shift in research approach. ANNALS OF BOTANY 2018; 121:1265-1273. [PMID: 29438453 PMCID: PMC6007437 DOI: 10.1093/aob/mcy009] [Citation(s) in RCA: 102] [Impact Index Per Article: 17.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/03/2017] [Accepted: 01/15/2018] [Indexed: 05/04/2023]
Abstract
BACKGROUND Silicon (Si) is known to have numerous beneficial effects on plants, alleviating diverse forms of abiotic and biotic stress. Research on this topic has accelerated in recent years and revealed multiple effects of Si in a range of plant species. Available information regarding the impact of Si on plant defence, growth and development is fragmented, discipline-specific, and usually focused on downstream, distal phenomena rather than underlying effects. Accordingly, there is a growing need for studies that address fundamental metabolic and regulatory processes, thereby allowing greater unification and focus of current research across disciplines. SCOPE AND CONCLUSIONS Silicon is often regarded as a plant nutritional 'non-entity'. A suite of factors associated with Si have been recently identified, relating to plant chemistry, physiology, gene regulation and interactions with other organisms. Research to date has typically focused on the impact of Si application upon plant stress responses. However, the fundamental, underlying mechanisms that account for the manifold effects of Si in plant biology remain undefined. Here, the known effects of Si in higher plants relating to alleviation of both abiotic and biotic stress are briefly reviewed and the potential importance of Si in plant primary metabolism is discussed, highlighting the need for a unifying research framework targeting common underlying mechanisms. The traditional approach of discipline-specific work on single stressors in individual plant species is currently inadequate. Thus, a holistic and comparative approach is proposed to assess the mode of action of Si between plant trait types (e.g. C3, C4 and CAM; Si accumulators and non-accumulators) and between biotic and abiotic stressors (pathogens, herbivores, drought, salt), considering potential pathways (i.e. primary metabolic processes) highlighted by recent empirical evidence. Utilizing genomic, transcriptomic, proteomic and metabolomic approaches in such comparative studies will pave the way for unification of the field and a deeper understanding of the role of Si in plants.
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Affiliation(s)
- Adam Frew
- School of Agricultural and Wine Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
- Graham Centre for Agricultural Innovation, Wagga Wagga, New South Wales, Australia
- For correspondence. E-mail
| | - Leslie A Weston
- School of Agricultural and Wine Sciences, Charles Sturt University, Wagga Wagga, New South Wales, Australia
- Graham Centre for Agricultural Innovation, Wagga Wagga, New South Wales, Australia
| | - Olivia L Reynolds
- Graham Centre for Agricultural Innovation, Wagga Wagga, New South Wales, Australia
- Biosecurity and Food Safety, New South Wales Department of Primary Industries, Narellan, New South Wales, Australia
- Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
| | - Geoff M Gurr
- Graham Centre for Agricultural Innovation, Wagga Wagga, New South Wales, Australia
- School of Agricultural and Wine Sciences, Charles Sturt University, Orange, New South Wales, Australia
- Institute of Applied Ecology, Fujian Agriculture and Forestry University, Fuzhou, Fujian, China
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