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See PT, Iagallo EM, Marathamuthu KA, Wood B, Aboukhaddour R, Moffat CS. A New ToxA Haplotype in the Wheat Fungal Pathogen Bipolaris sorokiniana. PHYTOPATHOLOGY 2024; 114:1525-1532. [PMID: 38530294 DOI: 10.1094/phyto-10-23-0370-r] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 03/27/2024]
Abstract
The necrotrophic effector ToxA is a well-studied virulence factor produced by several fungal necrotrophs. Initially cloned from the wheat tan spot pathogen Pyrenophora tritici-repentis in 1996, ToxA was found almost a decade later in another fungal pathogen, Parastagonospora nodorum, and its sister species, Parastagonospora pseudonodorum. In 2018, ToxA was detected in a third wheat fungal pathogenic species, Bipolaris sorokiniana, which causes spot blotch disease. However, unlike the case with P. tritici-repentis and P. nodorum, the ToxA in B. sorokiniana has only been investigated in recent years. In this report, five Australian B. sorokiniana isolates were assessed for the presence of ToxA. Four isolates were found to contain ToxA. While one isolate harbored the previously reported ToxA haplotype sequence (ToxA19), three isolates contain a different haplotype, designated herein as ToxA25, which has a nonsynonymous mutation resulting in an amino acid change of glycine to arginine at position 168. Both B. sorokiniana ToxA isoforms, when heterologously expressed in Escherichia coli, exhibited the classic ToxA necrosis-inducing activity on ToxA-sensitive Tsn1 cultivars. Preliminary analysis of the B. sorokiniana isolates in Australian wheat cultivars showed that isolates with ToxA19, ToxA25, or ToxA-deficient displayed various degrees of virulence, with the most aggressive isolates observed for those producing ToxA. Differences in spot blotch disease severity between Tsn1 and tsn1 cultivars were observed; however, this was not limited to the ToxA-producing isolates. The overall results suggest that the virulence of the Australian B. sorokiniana isolates is diverse, with the significance of ToxA-Tsn1 interactions depending on individual isolates.
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Affiliation(s)
- Pao Theen See
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA 6102, Australia
| | - Elyce M Iagallo
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA 6102, Australia
| | - Kalai A Marathamuthu
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA 6102, Australia
| | - Blake Wood
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA 6102, Australia
| | - Reem Aboukhaddour
- Agriculture and Agri-Food Canada, Lethbridge Research and Development Center, Lethbridge, Alberta, Canada
| | - Caroline S Moffat
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA 6102, Australia
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Kariyawasam GK, Nelson AC, Williams SJ, Solomon PS, Faris JD, Friesen TL. The Necrotrophic Pathogen Parastagonospora nodorum Is a Master Manipulator of Wheat Defense. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2023; 36:764-773. [PMID: 37581456 DOI: 10.1094/mpmi-05-23-0067-irw] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/16/2023]
Abstract
Parastagonospora nodorum is a necrotrophic pathogen of wheat that is particularly destructive in major wheat-growing regions of the United States, northern Europe, Australia, and South America. P. nodorum secretes necrotrophic effectors that target wheat susceptibility genes to induce programmed cell death (PCD), resulting in increased colonization of host tissue and, ultimately, sporulation to complete its pathogenic life cycle. Intensive research over the last two decades has led to the functional characterization of five proteinaceous necrotrophic effectors, SnTox1, SnToxA, SnTox267, SnTox3, and SnTox5, and three wheat susceptibility genes, Tsn1, Snn1, and Snn3D-1. Functional characterization has revealed that these effectors, in addition to inducing PCD, have additional roles in pathogenesis, including chitin binding that results in protection from wheat chitinases, blocking defense response signaling, and facilitating plant colonization. There are still large gaps in our understanding of how this necrotrophic pathogen is successfully manipulating wheat defense to complete its life cycle. This review summarizes our current knowledge, identifies knowledge gaps, and provides a summary of well-developed tools and resources currently available to study the P. nodorum-wheat interaction, which has become a model for necrotrophic specialist interactions. Further functional characterization of the effectors involved in this interaction and work toward a complete understanding of how P. nodorum manipulates wheat defense will provide fundamental knowledge about this and other necrotrophic interactions. Additionally, a broader understanding of this interaction will contribute to the successful management of Septoria nodorum blotch disease on wheat. [Formula: see text] Copyright © 2023 The Author(s). This is an open access article distributed under the CC BY-NC-ND 4.0 International license.
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Affiliation(s)
- Gayan K Kariyawasam
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58102, U.S.A
| | - Ashley C Nelson
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58102, U.S.A
| | - Simon J Williams
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Peter S Solomon
- Research School of Biology, The Australian National University, Canberra, ACT 2601, Australia
| | - Justin D Faris
- Cereal Crops Research Unit, USDA-ARS, Edward T. Schafer Agricultural Research Center, Fargo, ND 58102, U.S.A
| | - Timothy L Friesen
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58102, U.S.A
- Cereal Crops Research Unit, USDA-ARS, Edward T. Schafer Agricultural Research Center, Fargo, ND 58102, U.S.A
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Peters Haugrud AR, Zhang Z, Friesen TL, Faris JD. Genetics of resistance to septoria nodorum blotch in wheat. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2022; 135:3685-3707. [PMID: 35050394 DOI: 10.1007/s00122-022-04036-9] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2021] [Accepted: 12/23/2021] [Indexed: 05/12/2023]
Abstract
Septoria nodorum blotch (SNB) is a foliar disease of wheat caused by the necrotrophic fungal pathogen Parastagonospora nodorum. Research over the last two decades has shown that the wheat-P. nodorum pathosystem mostly follows an inverse gene-for-gene model. The fungus produces necrotrophic effectors (NEs) that interact with specific host gene products encoded by dominant sensitivity (S) genes. When a compatible interaction occurs, a 'defense response' in the host leads to programmed cell death thereby provided dead/dying cells from which the pathogen, being a necrotroph, can acquire nutrients allowing it to grow and sporulate. To date, nine S gene-NE interactions have been characterized in this pathosystem. Five NE-encoding genes, SnTox1, SnTox3, SnToxA, SnTox5, and SnTox267, have been cloned along with three host S genes, Tsn1, Snn1, and Snn3-D1. Studies have shown that P. nodorum hijacks multiple and diverse host targets to cause disease. SNB resistance is often quantitative in nature because multiple compatible interactions usually occur concomitantly. NE gene expression plays a key role in disease severity, and the effect of each compatible interaction can vary depending on the other existing compatible interactions. Numerous SNB-resistance QTL have been identified in addition to the known S genes, and more research is needed to understand the nature of these resistance loci. Marker-assisted elimination of S genes through conventional breeding practices and disruption of S genes using gene editing techniques are both effective strategies for the development of SNB-resistant wheat cultivars, which will become necessary as the global demand for sustenance grows.
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Affiliation(s)
| | - Zengcui Zhang
- USDA-ARS Cereal Crops Research Unit, Edward T. Schafer Agricultural Research Center, Fargo, ND, 58102, USA
| | - Timothy L Friesen
- USDA-ARS Cereal Crops Research Unit, Edward T. Schafer Agricultural Research Center, Fargo, ND, 58102, USA
| | - Justin D Faris
- USDA-ARS Cereal Crops Research Unit, Edward T. Schafer Agricultural Research Center, Fargo, ND, 58102, USA.
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John E, Jacques S, Phan HTT, Liu L, Pereira D, Croll D, Singh KB, Oliver RP, Tan KC. Variability in an effector gene promoter of a necrotrophic fungal pathogen dictates epistasis and effector-triggered susceptibility in wheat. PLoS Pathog 2022; 18:e1010149. [PMID: 34990464 PMCID: PMC8735624 DOI: 10.1371/journal.ppat.1010149] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2021] [Accepted: 11/26/2021] [Indexed: 12/31/2022] Open
Abstract
The fungus Parastagonospora nodorum uses proteinaceous necrotrophic effectors (NEs) to induce tissue necrosis on wheat leaves during infection, leading to the symptoms of septoria nodorum blotch (SNB). The NEs Tox1 and Tox3 induce necrosis on wheat possessing the dominant susceptibility genes Snn1 and Snn3B1/Snn3D1, respectively. We previously observed that Tox1 is epistatic to the expression of Tox3 and a quantitative trait locus (QTL) on chromosome 2A that contributes to SNB resistance/susceptibility. The expression of Tox1 is significantly higher in the Australian strain SN15 compared to the American strain SN4. Inspection of the Tox1 promoter region revealed a 401 bp promoter genetic element in SN4 positioned 267 bp upstream of the start codon that is absent in SN15, called PE401. Analysis of the world-wide P. nodorum population revealed that a high proportion of Northern Hemisphere isolates possess PE401 whereas the opposite was observed in representative P. nodorum isolates from Australia and South Africa. The presence of PE401 removed the epistatic effect of Tox1 on the contribution of the SNB 2A QTL but not Tox3. PE401 was introduced into the Tox1 promoter regulatory region in SN15 to test for direct regulatory roles. Tox1 expression was markedly reduced in the presence of PE401. This suggests a repressor molecule(s) binds PE401 and inhibits Tox1 transcription. Infection assays also demonstrated that P. nodorum which lacks PE401 is more pathogenic on Snn1 wheat varieties than P. nodorum carrying PE401. An infection competition assay between P. nodorum isogenic strains with and without PE401 indicated that the higher Tox1-expressing strain rescued the reduced virulence of the lower Tox1-expressing strain on Snn1 wheat. Our study demonstrated that Tox1 exhibits both 'selfish' and 'altruistic' characteristics. This offers an insight into a complex NE-NE interaction that is occurring within the P. nodorum population. The importance of PE401 in breeding for SNB resistance in wheat is discussed.
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Affiliation(s)
- Evan John
- Centre for Crop and Disease Management, Curtin University, Bentley, Perth, Western Australia, Australia
- Curtin University, Bentley, Perth, Western Australia, Australia
| | - Silke Jacques
- Centre for Crop and Disease Management, Curtin University, Bentley, Perth, Western Australia, Australia
- Curtin University, Bentley, Perth, Western Australia, Australia
| | - Huyen T. T. Phan
- Centre for Crop and Disease Management, Curtin University, Bentley, Perth, Western Australia, Australia
- Curtin University, Bentley, Perth, Western Australia, Australia
| | - Lifang Liu
- Centre for Crop and Disease Management, Curtin University, Bentley, Perth, Western Australia, Australia
- Curtin University, Bentley, Perth, Western Australia, Australia
| | - Danilo Pereira
- Plant Pathology, Institute of Integrative Biology, ETH Zurich, Zurich, Switzerland
| | - Daniel Croll
- Laboratory of Evolutionary Genetics, Institute of Biology, University of Neuchâtel, Neuchâtel, Switzerland
| | - Karam B. Singh
- Centre for Crop and Disease Management, Curtin University, Bentley, Perth, Western Australia, Australia
- Agriculture and Food, Commonwealth Scientific and Industrial Research Organisation, Floreat, Western Australia, Australia
| | | | - Kar-Chun Tan
- Centre for Crop and Disease Management, Curtin University, Bentley, Perth, Western Australia, Australia
- Curtin University, Bentley, Perth, Western Australia, Australia
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Katoch S, Sharma V, Sharma D, Salwan R, Rana SK. Biology and molecular interactions of Parastagonospora nodorum blotch of wheat. PLANTA 2021; 255:21. [PMID: 34914013 DOI: 10.1007/s00425-021-03796-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/17/2021] [Accepted: 11/14/2021] [Indexed: 06/14/2023]
Abstract
Parastagonospora nodorum is one of the important necrotrophic pathogens of wheat which causes severe economical loss to crop yield. So far, a number of effectors of Parastagonospora nodorum origin and their target interacting genes on the host plant have been characterized. Since targeting effector-sensitive gene carefully can be helpful in breeding for resistance. Therefore, constant efforts are required to further characterize the effectors, their interacting genes, and underlying biochemical pathways. Furthermore, to develop effective counter-strategies against emerging diseases, continuous efforts are required to determine the qualitative resistance that demands to screen of diverse genotypes for host resistance. Stagonospora nodorum blotch also refers to as Stagonospora glume blotch and leaf is caused by Parastagonospora nodorum. The pathogen deploys necrotrophic effectors for the establishment and development on wheat plants. The necrotrophic effectors and their interaction with host receptors lead to the establishment of infection on leaves and extensive lesions formation which either results in host cell death or suppression/activation of host defence mechanisms. The wheat Stagonospora nodorum interaction involves a set of nine host gene-necrotrophic effector interactions. Out of these, Snn1-SnTox1, Tsn1-SnToxA and Snn-SnTox3 are one of the most studied interaction, due to its role in the suppression of reactive oxygen species production, regulating the cytokinin content through ethylene-dependent wayduring initial infection stage. Further, although the molecular basis is not fully unveiled, these effectors regulate the redox state and influence the ethylene biosynthesis in infected wheat plants. Here, we have discussed the biology of the wheat pathogen Parastagonospora nodorum, role of its necrotrophic effectors and their interacting sensitivity genes on the redox state, how they hijack the resistance mechanisms, hormonal regulated immunity and other signalling pathways in susceptible wheat plants. The information generated from effectors and their corresponding sensitivity genes and other biological processes could be utilized effectively for disease management strategies.
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Affiliation(s)
- Shabnam Katoch
- Division of Plant Pathology, ICAR-Indian Agricultural Research Institute, New Delhi, 110012, India
| | - Vivek Sharma
- University Centre for Research and Development, Chandigarh University, Gharuan, 140413, Punjab, India.
| | - Devender Sharma
- Crop Improvement Division, ICAR-Vivekananda Parvatiya Krishi Anusandhan Sansthan, Almora, Uttarakhand, India
| | - Richa Salwan
- College of Horticulture and Forestry, Neri, Dr YS Parmar University of Horticulture and Forestry, Solan, Hamirpur, 177 001, India
| | - S K Rana
- Department of Plant Pathology, CSK HPKV Palampur, Palampur, 176062, Himachal Pradesh, India
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Veselova S, Nuzhnaya T, Burkhanova G, Rumyantsev S, Maksimov I. Reactive Oxygen Species in Host Plant Are Required for an Early Defense Response against Attack of Stagonospora nodorum Berk. Necrotrophic Effectors SnTox. PLANTS 2021; 10:plants10081586. [PMID: 34451631 PMCID: PMC8398409 DOI: 10.3390/plants10081586] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/29/2021] [Revised: 07/24/2021] [Accepted: 07/28/2021] [Indexed: 02/03/2023]
Abstract
Reactive oxygen species (ROS) play a central role in plant immune responses. The most important virulence factors of the Stagonospora nodorum Berk. are multiple fungal necrotrophic effectors (NEs) (SnTox) that affect the redox-status and cause necrosis and/or chlorosis in wheat lines possessing dominant susceptibility genes (Snn). However, the effect of NEs on ROS generation at the early stages of infection has not been studied. We studied the early stage of infection of various wheat genotypes with S nodorum isolates -Sn4VD, SnB, and Sn9MN, carrying a different set of NE genes. Our results indicate that all three NEs of SnToxA, SnTox1, SnTox3 significantly contributed to cause disease, and the virulence of the isolates depended on their differential expression in plants (Triticum aestivum L.). The Tsn1–SnToxA, Snn1–SnTox1and Snn3–SnTox3 interactions played an important role in inhibition ROS production at the initial stage of infection. The Snn3–SnTox3 inhibited ROS production in wheat by affecting NADPH-oxidases, peroxidases, superoxide dismutase and catalase. The Tsn1–SnToxA inhibited ROS production in wheat by affecting peroxidases and catalase. The Snn1–SnTox1 inhibited the production of ROS in wheat by mainly affecting a peroxidase. Collectively, these results show that the inverse gene-for gene interactions between effector of pathogen and product of host sensitivity gene suppress the host’s own PAMP-triggered immunity pathway, resulting in NE-triggered susceptibility (NETS). These results are fundamentally changing our understanding of the development of this economical important wheat disease.
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Affiliation(s)
- Svetlana Veselova
- Institute of Biochemistry and Genetics, Ufa Federal Research Centre, Russian Academy of Sciences, Prospekt Oktyabrya, 71, 450054 Ufa, Russia; (T.N.); (G.B.); (S.R.); (I.M.)
- Correspondence:
| | - Tatyana Nuzhnaya
- Institute of Biochemistry and Genetics, Ufa Federal Research Centre, Russian Academy of Sciences, Prospekt Oktyabrya, 71, 450054 Ufa, Russia; (T.N.); (G.B.); (S.R.); (I.M.)
- Ufa Institute of Biology, Ufa Federal Research Centre, Russian Academy of Sciences, Prospekt Oktyabrya, 69, 450054 Ufa, Russia
| | - Guzel Burkhanova
- Institute of Biochemistry and Genetics, Ufa Federal Research Centre, Russian Academy of Sciences, Prospekt Oktyabrya, 71, 450054 Ufa, Russia; (T.N.); (G.B.); (S.R.); (I.M.)
| | - Sergey Rumyantsev
- Institute of Biochemistry and Genetics, Ufa Federal Research Centre, Russian Academy of Sciences, Prospekt Oktyabrya, 71, 450054 Ufa, Russia; (T.N.); (G.B.); (S.R.); (I.M.)
| | - Igor Maksimov
- Institute of Biochemistry and Genetics, Ufa Federal Research Centre, Russian Academy of Sciences, Prospekt Oktyabrya, 71, 450054 Ufa, Russia; (T.N.); (G.B.); (S.R.); (I.M.)
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Downie RC, Lin M, Corsi B, Ficke A, Lillemo M, Oliver RP, Phan HTT, Tan KC, Cockram J. Septoria Nodorum Blotch of Wheat: Disease Management and Resistance Breeding in the Face of Shifting Disease Dynamics and a Changing Environment. PHYTOPATHOLOGY 2021; 111:906-920. [PMID: 33245254 DOI: 10.1094/phyto-07-20-0280-rvw] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
The fungus Parastagonospora nodorum is a narrow host range necrotrophic fungal pathogen that causes Septoria nodorum blotch (SNB) of cereals, most notably wheat (Triticum aestivum). Although commonly observed on wheat seedlings, P. nodorum infection has the greatest effect on the adult crop. It results in leaf blotch, which limits photosynthesis and thus crop growth and yield. It can also affect the wheat ear, resulting in glume blotch, which directly affects grain quality. Reports of P. nodorum fungicide resistance, the increasing use of reduced tillage agronomic practices, and high evolutionary potential of the pathogen, combined with changes in climate and agricultural environments, mean that genetic resistance to SNB remains a high priority in many regions of wheat cultivation. In this review, we summarize current information on P. nodorum population structure and its implication for improved SNB management. We then review recent advances in the genetics of host resistance to P. nodorum and the necrotrophic effectors it secretes during infection, integrating the genomic positions of these genetic loci by using the recently released wheat reference genome assembly. Finally, we discuss the genetic and genomic tools now available for SNB resistance breeding and consider future opportunities and challenges in crop health management by using the wheat-P. nodorum interaction as a model.
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Affiliation(s)
- Rowena C Downie
- John Bingham Laboratory, NIAB, Cambridge, CB3 0LE, United Kingdom
- Department of Plant Sciences, University of Cambridge, Cambridge, CB2 3EA, United Kingdom
| | - Min Lin
- Norwegian University of Life Sciences, Ås NO-1432, Norway
| | - Beatrice Corsi
- John Bingham Laboratory, NIAB, Cambridge, CB3 0LE, United Kingdom
| | - Andrea Ficke
- Norwegian Institute for Bioeconomy Research, Ås NO-1432, Norway
| | - Morten Lillemo
- Norwegian University of Life Sciences, Ås NO-1432, Norway
| | | | - Huyen T T Phan
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley 6102, Perth, WA, Australia
| | - Kar-Chun Tan
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley 6102, Perth, WA, Australia
| | - James Cockram
- John Bingham Laboratory, NIAB, Cambridge, CB3 0LE, United Kingdom
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Faris JD, Friesen TL. Plant genes hijacked by necrotrophic fungal pathogens. CURRENT OPINION IN PLANT BIOLOGY 2020; 56:74-80. [PMID: 32492572 DOI: 10.1016/j.pbi.2020.04.003] [Citation(s) in RCA: 47] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/02/2019] [Revised: 03/30/2020] [Accepted: 04/07/2020] [Indexed: 05/22/2023]
Abstract
Plant fungal pathogens can be classified according to their lifestyles. Biotrophs feed on living tissue and constitute an economically significant group of pathogens historically. Necrotrophs, which feed on dead tissue, have become economically significant over recent decades, especially those of the Dothideomycetes, which produce necrotrophic effectors (NEs) to modulate the host response. Some of these pathogens interact with their hosts in an inverse gene-for-gene manner, where NEs are recognized by specific dominant genes in the host leading to host-mediated programmed cell death allowing the pathogen to cause disease. Whereas the NE genes tend to be unique, several of the plant 'susceptibility' genes belong to the nucleotide-binding leucine-rich repeat class of disease 'resistance' genes, and one is a wall-associated kinase. These susceptible interactions exhibit hallmarks of defense responses to biotrophic pathogens. Therefore, there is now accumulating evidence that many necrotrophic specialists hijack the resistance mechanisms that are effective against biotrophic pathogens.
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Affiliation(s)
- Justin D Faris
- USDA-Agricultural Research Service, Cereal Crops Research Unit, Edward T. Schafer Agricultural Research Center, Fargo, ND 58102, United States.
| | - Timothy L Friesen
- USDA-Agricultural Research Service, Cereal Crops Research Unit, Edward T. Schafer Agricultural Research Center, Fargo, ND 58102, United States
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Lin M, Corsi B, Ficke A, Tan KC, Cockram J, Lillemo M. Genetic mapping using a wheat multi-founder population reveals a locus on chromosome 2A controlling resistance to both leaf and glume blotch caused by the necrotrophic fungal pathogen Parastagonospora nodorum. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2020; 133:785-808. [PMID: 31996971 PMCID: PMC7021668 DOI: 10.1007/s00122-019-03507-w] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 12/10/2019] [Indexed: 05/19/2023]
Abstract
KEY MESSAGE A locus on wheat chromosome 2A was found to control field resistance to both leaf and glume blotch caused by the necrotrophic fungal pathogen Parastagonospora nodorum. The necrotrophic fungal pathogen Parastagonospora nodorum is the causal agent of Septoria nodorum leaf blotch and glume blotch, which are common wheat (Triticum aestivum L.) diseases in humid and temperate areas. Susceptibility to Septoria nodorum leaf blotch can partly be explained by sensitivity to corresponding P. nodorum necrotrophic effectors (NEs). Susceptibility to glume blotch is also quantitative; however, the underlying genetics have not been studied in detail. Here, we genetically map resistance/susceptibility loci to leaf and glume blotch using an eight-founder wheat multiparent advanced generation intercross population. The population was assessed in six field trials across two sites and 4 years. Seedling infiltration and inoculation assays using three P. nodorum isolates were also carried out, in order to compare quantitative trait loci (QTL) identified under controlled conditions with those identified in the field. Three significant field resistance QTL were identified on chromosomes 2A and 6A, while four significant seedling resistance QTL were detected on chromosomes 2D, 5B and 7D. Among these, QSnb.niab-2A.3 for field resistance to both leaf blotch and glume blotch was detected in Norway and the UK. Colocation with a QTL for seedling reactions against culture filtrate from a Norwegian P. nodorum isolate indicated the QTL could be caused by a novel NE sensitivity. The consistency of this QTL for leaf blotch at the seedling and adult plant stages and culture filtrate infiltration was confirmed by haplotype analysis. However, opposite effects for the leaf blotch and glume blotch reactions suggest that different genetic mechanisms may be involved.
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Affiliation(s)
- Min Lin
- Department of Plant Sciences, Norwegian University of Life Sciences, Post Box 5003, 1432, Ås, Norway
| | - Beatrice Corsi
- John Bingham Laboratory, NIAB, Huntingdon Road, Cambridge, CB3 0LE, UK
| | - Andrea Ficke
- Norwegian Institute of Bioeconomy Research, Høgskoleveien 7, 1433, Ås, Norway
| | - Kar-Chun Tan
- Centre for Crop and Disease Management, School of Molecular and Life Sciences, Curtin University, Bentley, WA, Australia
| | - James Cockram
- John Bingham Laboratory, NIAB, Huntingdon Road, Cambridge, CB3 0LE, UK
| | - Morten Lillemo
- Department of Plant Sciences, Norwegian University of Life Sciences, Post Box 5003, 1432, Ås, Norway.
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Cowger C, Ward B, Brown-Guedira G, Brown JKM. Role of Effector-Sensitivity Gene Interactions and Durability of Quantitative Resistance to Septoria Nodorum Blotch in Eastern U.S. Wheat. FRONTIERS IN PLANT SCIENCE 2020; 11:155. [PMID: 32210986 PMCID: PMC7067980 DOI: 10.3389/fpls.2020.00155] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 01/31/2020] [Indexed: 05/02/2023]
Abstract
Important advances have been made in understanding the relationship of necrotrophic effectors (NE) and host sensitivity (Snn) genes in the Parastagonospora nodorum-wheat pathosystem. Yet much remains to be learned about the role of these interactions in determining wheat resistance levels in the field, and there is mixed evidence on whether breeding programs have selected against Snn genes due to their role in conferring susceptibility. SNB occurs ubiquitously in the U.S. Atlantic seaboard, and the environment is especially well suited to field studies of resistance to natural P. nodorum populations, as there are no other important wheat leaf blights. Insights into the nature of SNB resistance have been gleaned from multi-year data on phenotypes and markers in cultivars representative of the region's germplasm. In this perspective article, we review the evidence that in this eastern region of the U.S., wheat cultivars have durable quantitative SNB resistance and Snn-NE interactions are of limited importance. This conclusion is discussed in light of the relevant available information from other parts of the world.
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Affiliation(s)
- Christina Cowger
- U.S. Department of Agriculture – Agricultural Research Service, North Carolina State University, Raleigh, NC, United States
- *Correspondence: Christina Cowger,
| | - Brian Ward
- U.S. Department of Agriculture – Agricultural Research Service, North Carolina State University, Raleigh, NC, United States
| | - Gina Brown-Guedira
- U.S. Department of Agriculture – Agricultural Research Service, North Carolina State University, Raleigh, NC, United States
| | - James K. M. Brown
- Department of Crop Genetics, John Innes Centre, Norwich, United Kingdom
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Rodriguez-Moreno L, Ebert MK, Bolton MD, Thomma BPHJ. Tools of the crook- infection strategies of fungal plant pathogens. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2018; 93:664-674. [PMID: 29277938 DOI: 10.1111/tpj.13810] [Citation(s) in RCA: 48] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2017] [Revised: 12/18/2017] [Accepted: 12/18/2017] [Indexed: 05/14/2023]
Abstract
Fungi represent an ecologically diverse group of microorganisms that includes plant pathogenic species able to cause considerable yield loses in crop production systems worldwide. In order to establish compatible interactions with their hosts, pathogenic fungi rely on the secretion of molecules of diverse nature during host colonization to modulate host physiology, manipulate other environmental factors or provide self-defence. These molecules, collectively known as effectors, are typically small secreted cysteine-rich proteins, but may also comprise secondary metabolites and sRNAs. Here, we discuss the most common strategies that fungal plant pathogens employ to subvert their host plants in order to successfully complete their life cycle and secure the release of abundant viable progeny.
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Affiliation(s)
- Luis Rodriguez-Moreno
- Laboratory of Phytopathology, Wageningen University, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Malaika K Ebert
- Laboratory of Phytopathology, Wageningen University, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
| | - Melvin D Bolton
- USDA - Agricultural Research Service, Red River Valley Agricultural Research Center, Fargo, ND, USA
| | - Bart P H J Thomma
- Laboratory of Phytopathology, Wageningen University, Droevendaalsesteeg 1, 6708 PB, Wageningen, The Netherlands
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Downie RC, Bouvet L, Furuki E, Gosman N, Gardner KA, Mackay IJ, Campos Mantello C, Mellers G, Phan HTT, Rose GA, Tan KC, Oliver RP, Cockram J. Assessing European Wheat Sensitivities to Parastagonospora nodorum Necrotrophic Effectors and Fine-Mapping the Snn3-B1 Locus Conferring Sensitivity to the Effector SnTox3. FRONTIERS IN PLANT SCIENCE 2018. [PMID: 30022985 DOI: 10.3389/fpls.2017.0881] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Subscribe] [Scholar Register] [Indexed: 05/03/2023]
Abstract
Parastagonospora nodorum is a necrotrophic fungal pathogen of wheat (Triticum aestivum L.), one of the world's most important crops. P. nodorum mediates host cell death using proteinaceous necrotrophic effectors, presumably liberating nutrients that allow the infection process to continue. The identification of pathogen effectors has allowed host genetic resistance mechanisms to be separated into their constituent parts. In P. nodorum, three proteinaceous effectors have been cloned: SnToxA, SnTox1, and SnTox3. Here, we survey sensitivity to all three effectors in a panel of 480 European wheat varieties, and fine-map the wheat SnTox3 sensitivity locus Snn3-B1 using genome-wide association scans (GWAS) and an eight-founder wheat multi-parent advanced generation inter-cross (MAGIC) population. Using a Bonferroni corrected P ≤ 0.05 significance threshold, GWAS identified 10 significant markers defining a single locus, Snn3-B1, located on the short arm of chromosome 5B explaining 32% of the phenotypic variation [peak single nucleotide polymorphisms (SNPs), Excalibur_c47452_183 and GENE-3324_338, -log10P = 20.44]. Single marker analysis of SnTox3 sensitivity in the MAGIC population located Snn3-B1 via five significant SNPs, defining a 6.2-kb region that included the two peak SNPs identified in the association mapping panel. Accordingly, SNP Excalibur_c47452_183 was converted to the KASP genotyping system, and validated by screening a subset of 95 wheat varieties, providing a valuable resource for marker assisted breeding and for further genetic investigation. In addition, composite interval mapping in the MAGIC population identified six minor SnTox3 sensitivity quantitative trait loci, on chromosomes 2A (QTox3.niab-2A.1, P-value = 9.17-7), 2B (QTox3.niab-2B.1, P = 0.018), 3B (QTox3.niab-3B.1, P = 48.51-4), 4D (QTox3.niab-4D.1, P = 0.028), 6A (QTox3.niab-6A.1, P = 8.51-4), and 7B (QTox3.niab-7B.1, P = 0.020), each accounting for between 3.1 and 6.0 % of the phenotypic variance. Collectively, the outcomes of this study provides breeders with knowledge and resources regarding the sensitivity of European wheat germplasm to P. nodorum effectors, as well as simple diagnostic markers for determining allelic state at Snn3-B1.
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Affiliation(s)
- Rowena C Downie
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
- Plant Sciences Department, University of Cambridge, Cambridge, United Kingdom
| | - Laura Bouvet
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
- Plant Sciences Department, University of Cambridge, Cambridge, United Kingdom
| | - Eiko Furuki
- Centre for Crop and Disease Management, Curtin University, Perth, WA, Australia
| | - Nick Gosman
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Keith A Gardner
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Ian J Mackay
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Camila Campos Mantello
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Greg Mellers
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Huyen T T Phan
- Centre for Crop and Disease Management, Curtin University, Perth, WA, Australia
| | - Gemma A Rose
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Kar-Chun Tan
- Centre for Crop and Disease Management, Curtin University, Perth, WA, Australia
| | - Richard P Oliver
- Centre for Crop and Disease Management, Curtin University, Perth, WA, Australia
| | - James Cockram
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
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13
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Downie RC, Bouvet L, Furuki E, Gosman N, Gardner KA, Mackay IJ, Campos Mantello C, Mellers G, Phan HTT, Rose GA, Tan KC, Oliver RP, Cockram J. Assessing European Wheat Sensitivities to Parastagonospora nodorum Necrotrophic Effectors and Fine-Mapping the Snn3-B1 Locus Conferring Sensitivity to the Effector SnTox3. FRONTIERS IN PLANT SCIENCE 2018; 9:881. [PMID: 30022985 PMCID: PMC6039772 DOI: 10.3389/fpls.2018.00881] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Accepted: 06/06/2018] [Indexed: 05/18/2023]
Abstract
Parastagonospora nodorum is a necrotrophic fungal pathogen of wheat (Triticum aestivum L.), one of the world's most important crops. P. nodorum mediates host cell death using proteinaceous necrotrophic effectors, presumably liberating nutrients that allow the infection process to continue. The identification of pathogen effectors has allowed host genetic resistance mechanisms to be separated into their constituent parts. In P. nodorum, three proteinaceous effectors have been cloned: SnToxA, SnTox1, and SnTox3. Here, we survey sensitivity to all three effectors in a panel of 480 European wheat varieties, and fine-map the wheat SnTox3 sensitivity locus Snn3-B1 using genome-wide association scans (GWAS) and an eight-founder wheat multi-parent advanced generation inter-cross (MAGIC) population. Using a Bonferroni corrected P ≤ 0.05 significance threshold, GWAS identified 10 significant markers defining a single locus, Snn3-B1, located on the short arm of chromosome 5B explaining 32% of the phenotypic variation [peak single nucleotide polymorphisms (SNPs), Excalibur_c47452_183 and GENE-3324_338, -log10P = 20.44]. Single marker analysis of SnTox3 sensitivity in the MAGIC population located Snn3-B1 via five significant SNPs, defining a 6.2-kb region that included the two peak SNPs identified in the association mapping panel. Accordingly, SNP Excalibur_c47452_183 was converted to the KASP genotyping system, and validated by screening a subset of 95 wheat varieties, providing a valuable resource for marker assisted breeding and for further genetic investigation. In addition, composite interval mapping in the MAGIC population identified six minor SnTox3 sensitivity quantitative trait loci, on chromosomes 2A (QTox3.niab-2A.1, P-value = 9.17-7), 2B (QTox3.niab-2B.1, P = 0.018), 3B (QTox3.niab-3B.1, P = 48.51-4), 4D (QTox3.niab-4D.1, P = 0.028), 6A (QTox3.niab-6A.1, P = 8.51-4), and 7B (QTox3.niab-7B.1, P = 0.020), each accounting for between 3.1 and 6.0 % of the phenotypic variance. Collectively, the outcomes of this study provides breeders with knowledge and resources regarding the sensitivity of European wheat germplasm to P. nodorum effectors, as well as simple diagnostic markers for determining allelic state at Snn3-B1.
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Affiliation(s)
- Rowena C. Downie
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
- Plant Sciences Department, University of Cambridge, Cambridge, United Kingdom
- *Correspondence: Rowena C. Downie, James Cockram,
| | - Laura Bouvet
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
- Plant Sciences Department, University of Cambridge, Cambridge, United Kingdom
| | - Eiko Furuki
- Centre for Crop and Disease Management, Curtin University, Perth, WA, Australia
| | - Nick Gosman
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Keith A. Gardner
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Ian J. Mackay
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Camila Campos Mantello
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Greg Mellers
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Huyen T. T. Phan
- Centre for Crop and Disease Management, Curtin University, Perth, WA, Australia
| | - Gemma A. Rose
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
| | - Kar-Chun Tan
- Centre for Crop and Disease Management, Curtin University, Perth, WA, Australia
| | - Richard P. Oliver
- Centre for Crop and Disease Management, Curtin University, Perth, WA, Australia
| | - James Cockram
- Genetics and Breeding Department, National Institute of Agricultural Botany, Cambridge, United Kingdom
- *Correspondence: Rowena C. Downie, James Cockram,
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Abstract
The interactions between fungi and plants encompass a spectrum of ecologies ranging from saprotrophy (growth on dead plant material) through pathogenesis (growth of the fungus accompanied by disease on the plant) to symbiosis (growth of the fungus with growth enhancement of the plant). We consider pathogenesis in this article and the key roles played by a range of pathogen-encoded molecules that have collectively become known as effectors.
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Virdi SK, Liu Z, Overlander ME, Zhang Z, Xu SS, Friesen TL, Faris JD. New Insights into the Roles of Host Gene-Necrotrophic Effector Interactions in Governing Susceptibility of Durum Wheat to Tan Spot and Septoria nodorum Blotch. G3 (BETHESDA, MD.) 2016; 6:4139-4150. [PMID: 27777262 PMCID: PMC5144982 DOI: 10.1534/g3.116.036525] [Citation(s) in RCA: 32] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2016] [Accepted: 10/14/2016] [Indexed: 01/09/2023]
Abstract
Tan spot and Septoria nodorum blotch (SNB) are important diseases of wheat caused by the necrotrophic fungi Pyrenophora tritici-repentis and Parastagonospora nodorum, respectively. The P. tritici-repentis necrotrophic effector (NE) Ptr ToxB causes tan spot when recognized by the Tsc2 gene. The NE ToxA is produced by both pathogens and has been associated with the development of both tan spot and SNB when recognized by the wheat Tsn1 gene. Most work to study these interactions has been conducted in common wheat, but little has been done in durum wheat. Here, quantitative trait loci (QTL) analysis of a segregating biparental population indicated that the Tsc2-Ptr ToxB interaction plays a prominent role in the development of tan spot in durum. However, analysis of two biparental populations indicated that the Tsn1-ToxA interaction was not associated with the development of tan spot, but was strongly associated with the development of SNB. Pa. nodorum expressed ToxA at high levels in infected Tsn1 plants, whereas ToxA expression in P. tritici-repentis was barely detectable, suggesting that the differences in disease levels associated with the Tsn1-ToxA interaction were due to differences in pathogen expression of ToxA These and previous results together indicate that: (1) the effects of Tsn1-ToxA on tan spot in common wheat can range from nonsignificant to highly significant depending on the host genetic background; (2) Tsn1-ToxA is not a significant factor for tan spot development in durum wheat; and (3) Tsn1-ToxA plays a major role in SNB development in both common and durum wheat. Durum and common wheat breeders alike should strive to remove both Tsc2 and Tsn1 from their materials to achieve disease resistance.
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Affiliation(s)
- Simerjot K Virdi
- Department of Plant Sciences, North Dakota State University, Fargo, North Dakota 58108
| | - Zhaohui Liu
- Department of Plant Pathology, North Dakota State University, Fargo, North Dakota 58108
| | - Megan E Overlander
- United States Department of Agriculture-Agricultural Research Service, Cereal Cops Research Unit, Northern Crop Science Laboratory, Fargo, North Dakota 58102
| | - Zengcui Zhang
- United States Department of Agriculture-Agricultural Research Service, Cereal Cops Research Unit, Northern Crop Science Laboratory, Fargo, North Dakota 58102
| | - Steven S Xu
- United States Department of Agriculture-Agricultural Research Service, Cereal Cops Research Unit, Northern Crop Science Laboratory, Fargo, North Dakota 58102
| | - Timothy L Friesen
- Department of Plant Pathology, North Dakota State University, Fargo, North Dakota 58108
- United States Department of Agriculture-Agricultural Research Service, Cereal Cops Research Unit, Northern Crop Science Laboratory, Fargo, North Dakota 58102
| | - Justin D Faris
- United States Department of Agriculture-Agricultural Research Service, Cereal Cops Research Unit, Northern Crop Science Laboratory, Fargo, North Dakota 58102
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16
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Shi G, Zhang Z, Friesen TL, Raats D, Fahima T, Brueggeman RS, Lu S, Trick HN, Liu Z, Chao W, Frenkel Z, Xu SS, Rasmussen JB, Faris JD. The hijacking of a receptor kinase-driven pathway by a wheat fungal pathogen leads to disease. SCIENCE ADVANCES 2016; 2:e1600822. [PMID: 27819043 PMCID: PMC5091353 DOI: 10.1126/sciadv.1600822] [Citation(s) in RCA: 115] [Impact Index Per Article: 14.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2016] [Accepted: 09/27/2016] [Indexed: 05/18/2023]
Abstract
Necrotrophic pathogens live and feed on dying tissue, but their interactions with plants are not well understood compared to biotrophic pathogens. The wheat Snn1 gene confers susceptibility to strains of the necrotrophic pathogen Parastagonospora nodorum that produce the SnTox1 protein. We report the positional cloning of Snn1, a member of the wall-associated kinase class of receptors, which are known to drive pathways for biotrophic pathogen resistance. Recognition of SnTox1 by Snn1 activates programmed cell death, which allows this necrotroph to gain nutrients and sporulate. These results demonstrate that necrotrophic pathogens such as P. nodorum hijack host molecular pathways that are typically involved in resistance to biotrophic pathogens, revealing the complex nature of susceptibility and resistance in necrotrophic and biotrophic pathogen interactions with plants.
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Affiliation(s)
- Gongjun Shi
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58102, USA
| | - Zengcui Zhang
- U.S. Department of Agriculture (USDA) Agricultural Research Service, Cereal Crops Research Unit, Red River Valley Agricultural Research Center, Fargo, ND 58102, USA
| | - Timothy L. Friesen
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58102, USA
- U.S. Department of Agriculture (USDA) Agricultural Research Service, Cereal Crops Research Unit, Red River Valley Agricultural Research Center, Fargo, ND 58102, USA
| | - Dina Raats
- Institute of Evolution and Department of Evolutionary and Environmental Biology, University of Haifa, Mount Carmel, Haifa 3498838, Israel
| | - Tzion Fahima
- Institute of Evolution and Department of Evolutionary and Environmental Biology, University of Haifa, Mount Carmel, Haifa 3498838, Israel
| | - Robert S. Brueggeman
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58102, USA
| | - Shunwen Lu
- U.S. Department of Agriculture (USDA) Agricultural Research Service, Cereal Crops Research Unit, Red River Valley Agricultural Research Center, Fargo, ND 58102, USA
| | - Harold N. Trick
- Department of Plant Pathology, Kansas State University, Manhattan, KS 66506, USA
| | - Zhaohui Liu
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58102, USA
| | - Wun Chao
- USDA Agricultural Research Service, Sunflower and Plant Biology Research Unit, Red River Valley Agricultural Research Center, Fargo, ND 58102, USA
| | - Zeev Frenkel
- Institute of Evolution and Department of Evolutionary and Environmental Biology, University of Haifa, Mount Carmel, Haifa 3498838, Israel
| | - Steven S. Xu
- U.S. Department of Agriculture (USDA) Agricultural Research Service, Cereal Crops Research Unit, Red River Valley Agricultural Research Center, Fargo, ND 58102, USA
| | - Jack B. Rasmussen
- Department of Plant Pathology, North Dakota State University, Fargo, ND 58102, USA
| | - Justin D. Faris
- U.S. Department of Agriculture (USDA) Agricultural Research Service, Cereal Crops Research Unit, Red River Valley Agricultural Research Center, Fargo, ND 58102, USA
- Corresponding author.
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Proteome changes induced by Pyrenophora tritici-repentis ToxA in both insensitive and sensitive wheat indicate senescence-like signaling. Proteome Sci 2015; 13:3. [PMID: 25663824 PMCID: PMC4320625 DOI: 10.1186/s12953-014-0060-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2014] [Accepted: 12/23/2014] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND Pyrenophora tritici-repentis is a phytopathogenic fungus which causes tan spot on wheat. Some races of P. tritici-repentis produce host-specific toxins which present symptoms of chlorosis or necrosis on susceptible wheat cultivars. One such toxin is Ptr ToxA, which enters mesophyll cells through a putative toxin-receptor and localizes with chloroplasts, ultimately causing damage and necrosis on leaves. These symptoms can occur even in the absence of the pathogen. Insensitive cultivars lack the receptor and Ptr ToxA cannot enter cells. The molecular mechanisms surrounding this plant-pathogen interaction are still largely unknown, although some details have begun to emerge. RESULTS Using 2-D electrophoresis, fifteen protein changes were identified reproducibly in the leaf proteomes of a sensitive and an insensitive cultivar over three days after inoculation of purified Ptr ToxA. Functional analysis of the proteins indicated that senescence signals may be induced in the sensitive cultivar. In the insensitive cultivar proteins involved in some features of senescence inhibition were seen. Complementary responses at the biochemical level may be actively promoting a localized senescence-like response in sensitive wheat cultivars whilst actively inhibiting this response in insensitive cultivars. CONCLUSION This is the first report of a biochemical response in an insensitive cultivar in this plant-pathogen interaction. Findings support the involvement of ethylene, and the activation of complementary pathways in sensitive versus insensitive wheat cultivars responding to Ptr ToxA. The nature of the system permits using purified toxin to mimic disease, which eliminates the pathogen proteome and ensures a synchronous response in inoculated leaves.
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Tan KC, Phan HTT, Rybak K, John E, Chooi YH, Solomon PS, Oliver RP. Functional redundancy of necrotrophic effectors - consequences for exploitation for breeding. FRONTIERS IN PLANT SCIENCE 2015; 6:501. [PMID: 26217355 PMCID: PMC4495316 DOI: 10.3389/fpls.2015.00501] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
Necrotrophic diseases of wheat cause major losses in most wheat growing areas of world. Tan spot (caused by Pyrenophora tritici-repentis) and septoria nodorum blotch (SNB; Parastagonospora nodorum) have been shown to reduce yields by 10-20% across entire agri-ecological zones despite the application of fungicides and a heavy focus over the last 30 years on resistance breeding. Efforts by breeders to improve the resistance of cultivars has been compromised by the universal finding that resistance was quantitative and governed by multiple quantitative trait loci (QTL). Most QTL had a limited effect that was hard to measure precisely and varied significantly from site to site and season to season. The discovery of necrotrophic effectors has given breeding for disease resistance new methods and tools. In the case of tan spot in West Australia, a single effector, PtrToxA and its recogniser gene Tsn1, has a dominating impact in disease resistance. The delivery of ToxA to breeders has had a major impact on cultivar choice and breeding strategies. For P. nodorum, three effectors - SnToxA, SnTox1, and SnTox3 - have been well characterized. Unlike tan spot, no one effector has a dominating role. Genetic analysis of various mapping populations and pathogen isolates has shown that different effectors have varying impact and that epistatic interactions also occur. As a result of these factors the deployment of these effectors for SNB resistance breeding is more complex. We have deleted the three effectors in a strain of P. nodorum and measured effector activity and disease potential of the triple knockout mutant. The culture filtrate causes necrosis in several cultivars and the strain causes disease, albeit the overall levels are less than in the wild type. Modeling of the field disease resistance scores of cultivars from their reactions to the microbially expressed effectors SnToxA, SnTox1, and SnTox3 is significantly improved by including the response to the triple knockout mutant culture filtrate. This indicates that one or more further effectors are secreted into the culture filtrate. We conclude that the in vitro-secreted necrotrophic effectors explain a very large part of the disease response of wheat germplasm and that this method of resistance breeding promises to further reduce the impact of these globally significant diseases.
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Affiliation(s)
- Kar-Chun Tan
- Centre for Crop Disease Management, Department of Environment and Agriculture, Curtin University, BentleyWA, Australia
- *Correspondence: Richard P. Oliver and Kar-Chun Tan, Centre for Crop Disease Management, Department of Environment and Agriculture, Curtin University, Bentley, WA 6102, Australia, ;
| | - Huyen T. T. Phan
- Centre for Crop Disease Management, Department of Environment and Agriculture, Curtin University, BentleyWA, Australia
| | - Kasia Rybak
- Centre for Crop Disease Management, Department of Environment and Agriculture, Curtin University, BentleyWA, Australia
| | - Evan John
- Centre for Crop Disease Management, Department of Environment and Agriculture, Curtin University, BentleyWA, Australia
| | - Yit H. Chooi
- Plant Sciences Division, Research School of Biology, Australian National University, CanberraACT, Australia
- School of Chemistry and Biochemistry, University of Western Australia, PerthWA, Australia
| | - Peter S. Solomon
- Plant Sciences Division, Research School of Biology, Australian National University, CanberraACT, Australia
| | - Richard P. Oliver
- Centre for Crop Disease Management, Department of Environment and Agriculture, Curtin University, BentleyWA, Australia
- *Correspondence: Richard P. Oliver and Kar-Chun Tan, Centre for Crop Disease Management, Department of Environment and Agriculture, Curtin University, Bentley, WA 6102, Australia, ;
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Resequencing and comparative genomics of Stagonospora nodorum: sectional gene absence and effector discovery. G3-GENES GENOMES GENETICS 2013; 3:959-69. [PMID: 23589517 PMCID: PMC3689807 DOI: 10.1534/g3.112.004994] [Citation(s) in RCA: 34] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Stagonospora nodorum is an important wheat (Triticum aestivum) pathogen in many parts of the world, causing major yield losses. It was the first species in the large fungal Dothideomycete class to be genome sequenced. The reference genome sequence (SN15) has been instrumental in the discovery of genes encoding necrotrophic effectors that induce disease symptoms in specific host genotypes. Here we present the genome sequence of two further S. nodorum strains (Sn4 and Sn79) that differ in their effector repertoire from the reference. Sn79 is avirulent on wheat and produces no apparent effectors when infiltrated onto many cultivars and mapping population parents. Sn4 is pathogenic on wheat and has virulences not found in SN15. The new strains, sequenced with short-read Illumina chemistry, are compared with SN15 by a combination of mapping and de novo assembly approaches. Each of the genomes contains a large number of strain-specific genes, many of which have no meaningful similarity to any known gene. Large contiguous sections of the reference genome are absent in the two newly sequenced strains. We refer to these differences as “sectional gene absences.” The presence of genes in pathogenic strains and absence in Sn79 is added to computationally predicted properties of known proteins to produce a list of likely effector candidates. Transposon insertion was observed in the mitochondrial genomes of virulent strains where the avirulent strain retained the likely ancestral sequence. The study suggests that short-read enabled comparative genomics is an effective way to both identify new S. nodorum effector candidates and to illuminate evolutionary processes in this species.
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Friesen TL, Chu C, Xu SS, Faris JD. SnTox5-Snn5: a novel Stagonospora nodorum effector-wheat gene interaction and its relationship with the SnToxA-Tsn1 and SnTox3-Snn3-B1 interactions. MOLECULAR PLANT PATHOLOGY 2012; 13:1101-9. [PMID: 22830423 PMCID: PMC6638908 DOI: 10.1111/j.1364-3703.2012.00819.x] [Citation(s) in RCA: 50] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/18/2023]
Abstract
The Stagonospora nodorum-wheat interaction involves multiple pathogen-produced necrotrophic effectors that interact directly or indirectly with specific host gene products to induce the disease Stagonospora nodorum blotch (SNB). Here, we used a tetraploid wheat mapping population to identify and characterize a sixth effector-host gene interaction in the wheat-S. nodorum system. Initial characterization of the effector SnTox5 indicated that it is a proteinaceous necrotrophic effector that induces necrosis on host lines harbouring the Snn5 sensitivity gene, which was mapped to the long arm of wheat chromosome 4B. On the basis of ultrafiltration, SnTox5 is probably in the size range 10-30 kDa. Analysis of SNB development in the mapping population indicated that the SnTox5-Snn5 interaction explains 37%-63% of the variation, demonstrating that this interaction plays a significant role in disease development. When the SnTox5-Snn5 and SnToxA-Tsn1 interactions occurred together, the level of SNB was increased significantly. Similar to several other interactions in this system, the SnTox5-Snn5 interaction is light dependent, suggesting that multiple interactions may exploit the same pathways to cause disease.
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21
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Bouajila A, Zoghlami N, Ahmed MA, Baum M, Nazari K. Pathogenicity Spectra and Screening for Resistance in Barley Against Tunisian Pyrenophora teres f. teres. PLANT DISEASE 2012; 96:1569-1575. [PMID: 30727314 DOI: 10.1094/pdis-01-11-0072-re] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
This work aimed to determine patterns of pathogenicity in Pyrenophora teres f. teres and to identify potentially effective resistance sources that could be used as breeding material to control net blotch in Tunisia. Extensive pathogenic variability was detected in 85 isolates of P. teres causing net blotch of barley in Tunisia. Based on unweighted pair-group method with arithmetic averaging clustering and mean disease rating scores, three distinct virulence groups were identified. The isolates were classified into 23 pathotypes. Pathogenic variability within the groups was higher than that between the groups, a finding that can guide a rational choice of isolates for screening lines as part of a breeding program. Conversely, studying the relationship between geographic and pathotypic structure allowed us to detect a significant isolation by distance pattern, suggesting a regular and gradual dispersal of the pathogen over this spatial scale. Using specific resistance properties of individual barley genotypes as virulence markers, all the differential barley genotypes were shown to be distinct, and no single source of resistance was totally effective against all isolates.
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Affiliation(s)
- Aida Bouajila
- Centre de Biotechnologie de Borj-Cédria, BP 901, Hammam-Lif 2050, Tunisia
| | - Néjia Zoghlami
- Centre de Biotechnologie de Borj-Cédria, BP 901, Hammam-Lif 2050, Tunisia
| | - Maha Al Ahmed
- International Center for Agricultural Research in the Dry Areas (ICARDA), Aleppo, Syria; Abdelwahed Ghorbel, Centre de Biotechnologie de Borj-Cédria
| | - Michael Baum
- International Center for Agricultural Research in the Dry Areas (ICARDA), Aleppo, Syria; Abdelwahed Ghorbel, Centre de Biotechnologie de Borj-Cédria
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Tabib Ghaffary SM, Faris JD, Friesen TL, Visser RGF, van der Lee TAJ, Robert O, Kema GHJ. New broad-spectrum resistance to septoria tritici blotch derived from synthetic hexaploid wheat. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2012; 124:125-42. [PMID: 21912855 PMCID: PMC3249545 DOI: 10.1007/s00122-011-1692-7] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/22/2010] [Accepted: 08/18/2011] [Indexed: 05/04/2023]
Abstract
Septoria tritici blotch (STB), caused by the ascomycete Mycosphaerella graminicola, is one of the most devastating foliar diseases of wheat. We screened five synthetic hexaploid wheats (SHs), 13 wheat varieties that represent the differential set of cultivars and two susceptible checks with a global set of 20 isolates and discovered exceptionally broad STB resistance in SHs. Subsequent development and analyses of recombinant inbred lines (RILs) from a cross between the SH M3 and the highly susceptible bread wheat cv. Kulm revealed two novel resistance loci on chromosomes 3D and 5A. The 3D resistance was expressed in the seedling and adult plant stages, and it controlled necrosis (N) and pycnidia (P) development as well as the latency periods of these parameters. This locus, which is closely linked to the microsatellite marker Xgwm494, was tentatively designated Stb16q and explained from 41 to 71% of the phenotypic variation at seedling stage and 28-31% in mature plants. The resistance locus on chromosome 5A was specifically expressed in the adult plant stage, associated with SSR marker Xhbg247, explained 12-32% of the variation in disease, was designated Stb17, and is the first unambiguously identified and named QTL for adult plant resistance to M. graminicola. Our results confirm that common wheat progenitors might be a rich source of new Stb resistance genes/QTLs that can be deployed in commercial breeding programs.
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Affiliation(s)
- S. Mahmod Tabib Ghaffary
- Plant Research International, Biointeractions and Plant Health, P.O. Box 16, 6700 AA Wageningen, The Netherlands
- Graduate School of Experimental Plant Sciences, Wageningen University, Wageningen, The Netherlands
- Present Address: Safiabad Agricultural Research Centre, P.O. Box 333, Dezfoul, Iran
| | - Justin D. Faris
- Northern Crop Science Laboratory, USDA-ARS Cereal Crops Research Unit, 1307 18th Street North, Fargo, ND 58102-2765 USA
| | - Timothy L. Friesen
- Northern Crop Science Laboratory, USDA-ARS Cereal Crops Research Unit, 1307 18th Street North, Fargo, ND 58102-2765 USA
| | - Richard G. F. Visser
- Department of Plant Breeding, Wageningen University, P.O. Box 386, 6700 AJ Wageningen, The Netherlands
- Graduate School of Experimental Plant Sciences, Wageningen University, Wageningen, The Netherlands
| | - Theo A. J. van der Lee
- Plant Research International, Biointeractions and Plant Health, P.O. Box 16, 6700 AA Wageningen, The Netherlands
- Graduate School of Experimental Plant Sciences, Wageningen University, Wageningen, The Netherlands
| | - Olivier Robert
- Bioplante, Florimond Desprez, BP41, 59242 Cappelle-en-Pévèle, France
| | - Gert H. J. Kema
- Plant Research International, Biointeractions and Plant Health, P.O. Box 16, 6700 AA Wageningen, The Netherlands
- Graduate School of Experimental Plant Sciences, Wageningen University, Wageningen, The Netherlands
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23
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Oliver RP, Friesen TL, Faris JD, Solomon PS. Stagonospora nodorum: from pathology to genomics and host resistance. ANNUAL REVIEW OF PHYTOPATHOLOGY 2012; 50:23-43. [PMID: 22559071 DOI: 10.1146/annurev-phyto-081211-173019] [Citation(s) in RCA: 53] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/06/2023]
Abstract
Stagonospora nodorum is a major necrotrophic pathogen of wheat that causes the diseases S. nodorum leaf and glume blotch. A series of tools and resources, including functional genomics, a genome sequence, proteomics and metabolomics, host-mapping populations, and a worldwide collection of isolates, have enabled the dissection of pathogenicity mechanisms. Metabolic and signaling genes required for pathogenicity have been defined. Interaction with the host is dominated by interplay of fungal effectors that induce necrosis on wheat lines carrying specific sensitivity loci. As such, the pathogen has emerged as a model for the Pleosporales group of pathogens.
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Affiliation(s)
- Richard P Oliver
- Australian Center for Necrotrophic Fungal Pathogens, Curtin University, Perth WA 6845, Australia.
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24
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Faris JD, Zhang Z, Rasmussen JB, Friesen TL. Variable expression of the Stagonospora nodorum effector SnToxA among isolates is correlated with levels of disease in wheat. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2011; 24:1419-26. [PMID: 21770771 DOI: 10.1094/mpmi-04-11-0094] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/09/2023]
Abstract
Most research on host?pathogen interactions is focused on mechanisms of resistance, but less is known regarding mechanisms of susceptibility. The wheat?Stagonospora nodorum pathosystem involves pathogen-produced effectors, also known as host-selective toxins, that interact with corresponding dominant host genes to cause disease. Recognition of the S. nodorum effectors SnToxA and SnTox2 is mediated by the wheat genes Tsn1 and Snn2, respectively. Here, we inoculated a population of wheat recombinant inbred lines that segregates for Tsn1 and Snn2 with conidia from two S. nodorum isolates, Sn4 and Sn5, which both produce SnToxA and SnTox2 to compare the effects of compatible Tsn1?SnToxA and Snn2?SnTox2 interactions between the two isolates. Genetic analysis revealed that the two interactions contribute equally to disease caused by isolate Sn4 but the Tsn1?SnToxA interaction contributed substantially more to disease conferred by Sn5 than did the Snn2?SnTox2 interaction. Sequence analysis of the SnToxA locus from Sn4 and Sn5 indicated that they were 99.5% identical, with no polymorphisms in the coding region or the predicted promoters. Analysis of transcription levels showed that expression levels of SnToxA peaked at 26 h postinoculation for both isolates but SnToxA expression in Sn5 was more than twice that of Sn4. This work demonstrates that necrotrophic effectors of different isolates can be expressed at different levels in planta, and that higher levels of expression lead to increased levels of disease in the wheat?S. nodorum pathosystem.
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Affiliation(s)
- Justin D Faris
- United States Department of Agriculture, Fargo, ND, USA.
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25
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Tabib Ghaffary SM, Robert O, Laurent V, Lonnet P, Margalé E, van der Lee TAJ, Visser RGF, Kema GHJ. Genetic analysis of resistance to septoria tritici blotch in the French winter wheat cultivars Balance and Apache. TAG. THEORETICAL AND APPLIED GENETICS. THEORETISCHE UND ANGEWANDTE GENETIK 2011; 123:741-54. [PMID: 21655994 PMCID: PMC3155673 DOI: 10.1007/s00122-011-1623-7] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/27/2010] [Accepted: 05/18/2011] [Indexed: 05/21/2023]
Abstract
The ascomycete Mycosphaerella graminicola is the causal agent of septoria tritici blotch (STB), one of the most destructive foliar diseases of bread and durum wheat globally, particularly in temperate humid areas. A screening of the French bread wheat cultivars Apache and Balance with 30 M. graminicola isolates revealed a pattern of resistant responses that suggested the presence of new genes for STB resistance. Quantitative trait loci (QTL) analysis of a doubled haploid (DH) population with five M. graminicola isolates in the seedling stage identified four QTLs on chromosomes 3AS, 1BS, 6DS and 7DS, and occasionally on 7DL. The QTL on chromosome 6DS flanked by SSR markers Xgpw5176 and Xgpw3087 is a novel QTL that now can be designated as Stb18. The QTLs on chromosomes 3AS and 1BS most likely represent Stb6 and Stb11, respectively, and the QTLs on chromosome 7DS are most probably identical with Stb4 and Stb5. However, the QTL identified on chromosome 7DL is expected to be a new Stb gene that still needs further characterization. Multiple isolates were used and show that not all isolates identify all QTLs, which clearly demonstrates the specificity in the M. graminicola-wheat pathosystem. QTL analyses were performed with various disease parameters. The development of asexual fructifications (pycnidia) in the characteristic necrotic blotches of STB, designated as parameter P, identified the maximum number of QTLs. All other parameters identified fewer but not different QTLs. The segregation of multiple QTLs in the Apache/Balance DH population enabled the identification of DH lines with single QTLs and multiple QTL combinations. Analyses of the marker data of these DH lines clearly demonstrated the positive effect of pyramiding QTLs to broaden resistance spectra as well as epistatic and additive interactions between these QTLs. Phenotyping of the Apache/Balance DH population in the field confirmed the presence of the QTLs that were identified in the seedling stage, but Stb18 was inconsistently expressed and might be particularly effective in young plants. In contrast, an additional QTL for STB resistance was identified on chromosome 2DS that is exclusively and consistently expressed in mature plants over locations and time, but it was also strongly related with earliness, tallness as well as resistance to Fusarium head blight. Although to date no Stb gene has been reported on chromosome 2D, the data provide evidence that this QTL is only indirectly related to STB resistance. This study shows that detailed genetic analysis of contemporary commercial bread wheat cultivars can unveil novel Stb genes that can be readily applied in marker-assisted breeding programs.
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Affiliation(s)
- Seyed Mahmod Tabib Ghaffary
- Plant Research International, Biointeractions and Plant Health, P.O. Box 16, 6700 AA Wageningen, The Netherlands
- Graduate School of Experimental Plant Sciences, Wageningen, The Netherlands
| | - Olivier Robert
- Bioplante, 3 Rue Florimond Desprez, BP41, 59242 Cappelle-en-Pévèle, France
| | - Valerie Laurent
- Bioplante, 3 Rue Florimond Desprez, BP41, 59242 Cappelle-en-Pévèle, France
| | - Philippe Lonnet
- Florimond Desprez, 3 Rue Florimond Desprez, BP41, 59242 Cappelle-en-Pévèle, France
| | - Eric Margalé
- Serasem, 60, Rue Léon Beauchamp, 59930 La Chapelle d’Armentières, France
| | - Theo A. J. van der Lee
- Plant Research International, Biointeractions and Plant Health, P.O. Box 16, 6700 AA Wageningen, The Netherlands
| | - Richard G. F. Visser
- Laboratory of Plant Breeding, Wageningen University, P.O. Box 386, 6700 AJ Wageningen, The Netherlands
| | - Gert H. J. Kema
- Plant Research International, Biointeractions and Plant Health, P.O. Box 16, 6700 AA Wageningen, The Netherlands
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Zhang Z, Friesen TL, Xu SS, Shi G, Liu Z, Rasmussen JB, Faris JD. Two putatively homoeologous wheat genes mediate recognition of SnTox3 to confer effector-triggered susceptibility to Stagonospora nodorum. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2011; 65:27-38. [PMID: 21175887 DOI: 10.1111/j.1365-313x.2010.04407.x] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/07/2023]
Abstract
The pathogen Stagonospora nodorum produces multiple effectors, also known as host-selective toxins (HSTs), that interact with corresponding host sensitivity genes in an inverse gene-for-gene manner to cause the disease Stagonospora nodorum blotch (SNB) in wheat. In this study, a sensitivity gene was identified in Aegilops tauschii, the diploid D-genome donor of common wheat. The gene was mapped to the short arm of chromosome 5D and mediated recognition of the effector SnTox3, which was previously shown to be recognized by the wheat gene Snn3 on chromosome arm 5BS. Comparative mapping suggested that Snn3 and the gene on 5DS are probably homoeologous and derived from a common ancestor. Therefore, we propose to designate these genes as Snn3-B1 and Snn3-D1, respectively. Compatible Snn3-D1-SnTox3 interactions resulted in more severe necrosis in both effector infiltration and spore inoculation experiments than compatible Snn3-B1-SnTox3 interactions, indicating that Snn3-B1 and Snn3-D1 may have different affinities in SnTox3 recognition or signal transduction. Wheat bin-mapped expressed sequence tags and good levels of collinearity among the wheat Snn3 regions, rice (Oryza sativa), and Brachypodium distachyon were exploited for saturation and fine mapping of the Snn3-D1 locus. Markers delineating the Snn3-D1 locus to a 1.4 cM interval will be useful for initiating positional cloning. Further characterization of how these homoeologous genes mediate recognition of the same pathogen effector should enhance understanding of host manipulation by necrotrophic pathogens in causing disease.
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Affiliation(s)
- Zengcui Zhang
- Department of Plant Pathology, Walster Hall, North Dakota State University, Fargo, ND 58102, USAUSDA-Agricultural Research Service, Cereal Crops Research Unit, 1307 18th Street North, Fargo, ND 58102-2765, USA
| | - Timothy L Friesen
- Department of Plant Pathology, Walster Hall, North Dakota State University, Fargo, ND 58102, USAUSDA-Agricultural Research Service, Cereal Crops Research Unit, 1307 18th Street North, Fargo, ND 58102-2765, USA
| | - Steven S Xu
- Department of Plant Pathology, Walster Hall, North Dakota State University, Fargo, ND 58102, USAUSDA-Agricultural Research Service, Cereal Crops Research Unit, 1307 18th Street North, Fargo, ND 58102-2765, USA
| | - Gongjun Shi
- Department of Plant Pathology, Walster Hall, North Dakota State University, Fargo, ND 58102, USAUSDA-Agricultural Research Service, Cereal Crops Research Unit, 1307 18th Street North, Fargo, ND 58102-2765, USA
| | - Zhaohui Liu
- Department of Plant Pathology, Walster Hall, North Dakota State University, Fargo, ND 58102, USAUSDA-Agricultural Research Service, Cereal Crops Research Unit, 1307 18th Street North, Fargo, ND 58102-2765, USA
| | - Jack B Rasmussen
- Department of Plant Pathology, Walster Hall, North Dakota State University, Fargo, ND 58102, USAUSDA-Agricultural Research Service, Cereal Crops Research Unit, 1307 18th Street North, Fargo, ND 58102-2765, USA
| | - Justin D Faris
- Department of Plant Pathology, Walster Hall, North Dakota State University, Fargo, ND 58102, USAUSDA-Agricultural Research Service, Cereal Crops Research Unit, 1307 18th Street North, Fargo, ND 58102-2765, USA
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27
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Antony G, Zhou J, Huang S, Li T, Liu B, White F, Yang B. Rice xa13 recessive resistance to bacterial blight is defeated by induction of the disease susceptibility gene Os-11N3. THE PLANT CELL 2010; 22:3864-76. [PMID: 21098734 PMCID: PMC3015117 DOI: 10.1105/tpc.110.078964] [Citation(s) in RCA: 304] [Impact Index Per Article: 21.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/20/2010] [Revised: 10/08/2010] [Accepted: 11/08/2010] [Indexed: 05/18/2023]
Abstract
The rice (Oryza sativa) gene xa13 is a recessive resistance allele of Os-8N3, a member of the NODULIN3 (N3) gene family, located on rice chromosome 8. Os-8N3 is a susceptibility (S) gene for Xanthomonas oryzae pv oryzae, the causal agent of bacterial blight, and the recessive allele is defeated by strains of the pathogen producing any one of the type III effectors AvrXa7, PthXo2, or PthXo3, which are all members of the transcription activator-like (TAL) effector family. Both AvrXa7 and PthXo3 induce the expression of a second member of the N3 gene family, here named Os-11N3. Insertional mutagenesis or RNA-mediated silencing of Os-11N3 resulted in plants with loss of susceptibility specifically to strains of X. oryzae pv oryzae dependent on AvrXa7 or PthXo3 for virulence. We further show that AvrXa7 drives expression of Os-11N3 and that AvrXa7 interacts and binds specifically to an effector binding element within the Os-11N3 promoter, lending support to the predictive models for TAL effector binding specificity. The result indicates that variations in the TAL effector repetitive domains are driven by selection to overcome both dominant and recessive forms of resistance to bacterial blight in rice. The finding that Os-8N3 and Os-11N3 encode closely related proteins also provides evidence that N3 proteins have a specific function in facilitating bacterial blight disease.
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Affiliation(s)
- Ginny Antony
- Department of Plant Pathology, Kansas State University, Manhattan, Kansas 66506
| | - Junhui Zhou
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50011
| | - Sheng Huang
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50011
| | - Ting Li
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50011
| | - Bo Liu
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50011
| | - Frank White
- Department of Plant Pathology, Kansas State University, Manhattan, Kansas 66506
| | - Bing Yang
- Department of Genetics, Development, and Cell Biology, Iowa State University, Ames, Iowa 50011
- Address correspondence to
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