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Dilla-Ermita CJ, Goldman P, Anchieta A, Feldmann MJ, Pincot DDA, Famula RA, Vachev M, Cole GS, Knapp SJ, Klosterman SJ, Henry PM. Secreted in Xylem 6 ( SIX6) Mediates Fusarium oxysporum f. sp. fragariae Race 1 Avirulence on FW1-Resistant Strawberry Cultivars. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2024; 37:530-541. [PMID: 38552146 DOI: 10.1094/mpmi-02-24-0012-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: 06/25/2024]
Abstract
Fusarium oxysporum f. sp. fragariae (Fof) race 1 is avirulent on cultivars with the dominant resistance gene FW1, while Fof race 2 is virulent on FW1-resistant cultivars. We hypothesized there was a gene-for-gene interaction between a gene at the FW1 locus and an avirulence gene (AvrFW1) in Fof race 1. To identify a candidate AvrFW1, we compared genomes of 24 Fof race 1 and three Fof race 2 isolates. We found one candidate gene that was present in race 1, was absent in race 2, was highly expressed in planta, and was homologous to a known effector, secreted in xylem 6 (SIX6). We knocked out SIX6 in two Fof race 1 isolates by homologous recombination. All SIX6 knockout transformants (ΔSIX6) gained virulence on FW1/fw1 cultivars, whereas ectopic transformants and the wildtype isolates remained avirulent. ΔSIX6 isolates were quantitatively less virulent on FW1/fw1 cultivars Fronteras and San Andreas than fw1/fw1 cultivars. Seedlings from an FW1/fw1 × fw1/fw1 population were genotyped for FW1 and tested for susceptibility to a SIX6 knockout isolate. Results suggested that additional minor-effect quantitative resistance genes could be present at the FW1 locus. This work demonstrates that SIX6 acts as an avirulence factor interacting with a resistance gene at the FW1 locus. The identification of AvrFW1 enables surveillance for Fof race 2 and provides insight into the mechanisms of FW1-mediated resistance. [Formula: see text] Copyright © 2024 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)
- Christine Jade Dilla-Ermita
- Crop Improvement and Protection Research, USDA-ARS, 1636 E. Alisal St., Salinas, CA 93905
- Department of Plant Sciences, University of California Davis, One Shields Ave., Davis, CA 95616
| | - Polly Goldman
- Crop Improvement and Protection Research, USDA-ARS, 1636 E. Alisal St., Salinas, CA 93905
| | - Amy Anchieta
- Crop Improvement and Protection Research, USDA-ARS, 1636 E. Alisal St., Salinas, CA 93905
| | - Mitchell J Feldmann
- Department of Plant Sciences, University of California Davis, One Shields Ave., Davis, CA 95616
| | - Dominique D A Pincot
- Department of Plant Sciences, University of California Davis, One Shields Ave., Davis, CA 95616
| | - Randi A Famula
- Department of Plant Sciences, University of California Davis, One Shields Ave., Davis, CA 95616
| | - Mishi Vachev
- Department of Plant Sciences, University of California Davis, One Shields Ave., Davis, CA 95616
| | - Glenn S Cole
- Department of Plant Sciences, University of California Davis, One Shields Ave., Davis, CA 95616
| | - Steven J Knapp
- Department of Plant Sciences, University of California Davis, One Shields Ave., Davis, CA 95616
| | - Steven J Klosterman
- Crop Improvement and Protection Research, USDA-ARS, 1636 E. Alisal St., Salinas, CA 93905
| | - Peter M Henry
- Crop Improvement and Protection Research, USDA-ARS, 1636 E. Alisal St., Salinas, CA 93905
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Rathore AS, Gupta KK, Chandrasekaran J, Chandran SA. In silico identification of a promising inhibitor of Fusarium oxysporum f. sp. Lycopersici, Secreted in Xylem 1 protein. Mol Divers 2024; 28:711-725. [PMID: 36735168 DOI: 10.1007/s11030-023-10613-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/16/2022] [Accepted: 01/25/2023] [Indexed: 02/04/2023]
Abstract
Fusarium oxysporum f. sp. Lycopersici (FOL) is a soilborne pathogen that infects tomato plants and inflicts severe damage, resulting in heavy yield losses worldwide, causing Fusarium wilt disease. FOL encodes several pathogenicity factors necessary for colonizing and invading the host plants. Secreted in Xylem (SIX), a pathogenicity factor, is a small cysteine-rich fungal protein found in the xylem sap of FOL-infected tomato plants, which plays a major role in determining host specificity and in contributing to pathogenicity/virulence. However, the structure of SIX1 has not been modeled yet. Therefore, this study aimed to elucidate the structure of SIX1 by comparative modeling using Robetta server. The best possible structures obtained were then refined, validated, and utilized for subsequent analysis. An antifungal library comprising 16,824 compounds was screened to determine small molecules that can interact with SIX1. Five antifungal compounds were identified from the library. Further analyses revealed that, of the five ligands, 4-[(2-(3-methoxyphenoxy)acetyl)amino] benzamide exhibited the capacity to stably interact with SIX1. This shows that 4-[[2-(3-methoxyphenoxy)acetyl]amino] benzamide can be used as a potential candidate in the prevention of FOL infection. In summary, small-molecule inhibitors such as 4-[[2-(3-methoxyphenoxy)acetyl]amino] benzamide could be highly effective in combating FOL infection, along with biocontrol methods and strategies that use transgenic plants overexpressing resistance genes.
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Affiliation(s)
- Anuranjan Singh Rathore
- School of Chemical and Biotechnology, SASTRA Deemed to Be University, Thanjavur, Tamil Nadu, India
| | - Krishna Kant Gupta
- School of Chemical and Biotechnology, SASTRA Deemed to Be University, Thanjavur, Tamil Nadu, India
| | | | - Sam Aldrin Chandran
- School of Chemical and Biotechnology, SASTRA Deemed to Be University, Thanjavur, Tamil Nadu, India.
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Chellappan BV, El-Ganainy SM, Alrajeh HS, Al-Sheikh H. In Silico Characterization of the Secretome of the Fungal Pathogen Thielaviopsis punctulata, the Causal Agent of Date Palm Black Scorch Disease. J Fungi (Basel) 2023; 9:jof9030303. [PMID: 36983471 PMCID: PMC10051545 DOI: 10.3390/jof9030303] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/27/2023] [Revised: 02/23/2023] [Accepted: 02/24/2023] [Indexed: 03/03/2023] Open
Abstract
The black scorch disease of date palm caused by Thielaviopsis punctulata is a serious threat to the cultivation and productivity of date palm in Arabian Peninsula. The virulence factors that contribute to pathogenicity of T. punctulata have not been identified yet. In the present study, using bioinformatics approach, secretory proteins of T. punctulata were identified and functionally characterized. A total of 197 putative secretory proteins were identified, of which 74 were identified as enzymes for carbohydrate degradation (CAZymes), 25 were proteases, and 47 were predicted as putative effectors. Within the CAZymes, 50 cell wall-degrading enzymes, potentially to degrade cell wall components such as cellulose, hemicellulose, lignin, and pectin, were identified. Of the 47 putative effectors, 34 possessed at least one functional domain. The secretome of T. punctulata was compared to the predicted secretome of five closely related species (T. musarum, T. ethacetica, T. euricoi, T. cerberus, and T. populi) and identified species specific CAZymes and putative effector genes in T. punctulata, providing a valuable resource for the research aimed at understanding the molecular mechanism underlying the pathogenicity of T. punctulata on Date palm.
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Affiliation(s)
- Biju Vadakkemukadiyil Chellappan
- Department of Biological Sciences, College of Science, King Faisal University, P.O. Box 420, Al-Ahsa 31982, Saudi Arabia
- Correspondence:
| | - Sherif Mohamed El-Ganainy
- Department of Arid Land Agriculture, College of Agriculture and Food Sciences, King Faisal University, P.O. Box 420, Al-Ahsa 31982, Saudi Arabia
- Agricultural Research Center, Plant Pathology Research Institute, Giza 12619, Egypt
| | - Hind Salih Alrajeh
- Department of Biological Sciences, College of Science, King Faisal University, P.O. Box 420, Al-Ahsa 31982, Saudi Arabia
| | - Hashem Al-Sheikh
- Department of Biological Sciences, College of Science, King Faisal University, P.O. Box 420, Al-Ahsa 31982, Saudi Arabia
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Pazarlar S, Madriz-Ordeñana K, Thordal-Christensen H. Bacillus cereus EC9 protects tomato against Fusarium wilt through JA/ET-activated immunity. FRONTIERS IN PLANT SCIENCE 2022; 13:1090947. [PMID: 36589090 PMCID: PMC9798288 DOI: 10.3389/fpls.2022.1090947] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/06/2022] [Accepted: 11/29/2022] [Indexed: 06/17/2023]
Abstract
The mechanisms of action and the limitations of effectiveness of natural biocontrol agents should be determined in order to convert them into end products that can be used in practice. Rhizosphere Bacillus spp. protect plants from various pathogens by displaying several modes of action. However, the ability of Bacillus spp. to control plant diseases depends on the interaction between the bacteria, host, and pathogen, and the environmental conditions. We found that soil drenching of tomato plants with the non-antifungal Bacillus cereus strain EC9 (EC9) enhances plant defense against Fusarium oxysporum f. sp. lycopersici (Fol). To study the involvement of plant defense-related phytohormones in the regulation of EC9-activated protection against Fol, we conducted plant bioassays in tomato genotypes impaired in salicylic acid (SA) accumulation, jasmonic acid (JA) biosynthesis, and ethylene (ET) production, and analyzed the transcript levels of pathways-related marker genes. Our results indicate that JA/ET-dependent signaling is required for EC9-mediated protection against Fol in tomato. We provide evidence that EC9 primes tomato plants for enhanced expression of proteinase inhibitor I (PI-I) and ethylene receptor4 (ETR4). Moreover, we demonstrated that EC9 induces callose deposition in tomato roots. Understanding the involvement of defense-related phytohormones in EC9-mediated defense against Fusarium wilt has increased our knowledge of interactions between non-antifungal plant defense-inducing rhizobacteria and plants.
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Affiliation(s)
- Sercan Pazarlar
- Department of Plant Protection, Faculty of Agriculture, Ege University, Izmir, Turkey
- Department of Plant and Environmental Sciences, Section for Plant and Soil Science, University of Copenhagen, Copenhagen, Denmark
| | - Kenneth Madriz-Ordeñana
- Department of Plant and Environmental Sciences, Section for Plant and Soil Science, University of Copenhagen, Copenhagen, Denmark
| | - Hans Thordal-Christensen
- Department of Plant and Environmental Sciences, Section for Plant and Soil Science, University of Copenhagen, Copenhagen, Denmark
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Interaction Studies between Meloidogyne javanica and Fusarium oxysporum f. sp. lycopersici (Fol) Race 3 on Different Isolines of Tomato cv. Tasti Lee. J Nematol 2022; 54:20220018. [PMID: 35975222 PMCID: PMC9338710 DOI: 10.2478/jofnem-2022-0018] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2022] [Indexed: 11/23/2022] Open
Abstract
The Mi gene in tomato confers resistance to Meloidogyne javanica, M. incognita, and M. arenaria, the most common tropical root-knot nematode (RKN) species found in Florida. Fusarium wilt (Fol) is another major problem in Florida tomatoes which may interact with RKN and cause more plant damage. To study the interactions between RKN, Fusarium, and Mi in tomato, two greenhouse experiments were conducted. Both experiments used different isolines (with and without I-3 and Mi genes) of the tomato cultivar Tasti Lee®. In the first experiment, all four isolines were subjected to two levels of RKN (~10,000 eggs/pot and no eggs) and two levels of Fol (1000 cc soil with 1,000 cfu/g at planting and no Fol), both applied at planting. In the second experiment, the two isolines without I-3 were exposed to the same two levels of RKN as described above and three levels of Fol (50 ml Fol with 1×106 cfu/m at planting, at 10 DAT, and no Fol). Fol reduced root-knot infection and reproduction when both Fol and RKN were inoculated at planting but not when Fol was inoculated 10 days later. Plant damage from Fol was exacerbated in the presence of RKN, especially when both pathogens were present at planting. Isolines with I-3 grew better in Fol-inoculated soil but had no effect when Fol and RKN were both present. Isolines with Mi gene reduced RKN infection and reproduction but did not affect plant damage caused by Fol. In summary, while RKN reproduction was reduced in the presence of Fol, the overall plant damage was more severe when both pathogens were present.
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Jangir P, Mehra N, Sharma K, Singh N, Rani M, Kapoor R. Secreted in Xylem Genes: Drivers of Host Adaptation in Fusarium oxysporum. FRONTIERS IN PLANT SCIENCE 2021; 12:628611. [PMID: 33968096 PMCID: PMC8101498 DOI: 10.3389/fpls.2021.628611] [Citation(s) in RCA: 18] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/12/2020] [Accepted: 03/01/2021] [Indexed: 05/17/2023]
Abstract
Fusarium oxysporum (Fo) is a notorious pathogen that significantly contributes to yield losses in crops of high economic status. It is responsible for vascular wilt characterized by the browning of conductive tissue, wilting, and plant death. Individual strains of Fo are host specific (formae speciales), and approximately, 150 forms have been documented so far. The pathogen secretes small effector proteins in the xylem, termed as Secreted in Xylem (Six), that contribute to its virulence. Most of these proteins contain cysteine residues in even numbers. These proteins are encoded by SIX genes that reside on mobile pathogenicity chromosomes. So far, 14 proteins have been reported. However, formae speciales vary in SIX protein profile and their respective gene sequence. Thus, SIX genes have been employed as ideal markers for pathogen identification. Acquisition of SIX-encoding mobile pathogenicity chromosomes by non-pathogenic lines, through horizontal transfer, results in the evolution of new virulent lines. Recently, some SIX genes present on these pathogenicity chromosomes have been shown to be involved in defining variation in host specificity among formae speciales. Along these lines, the review entails the variability (formae speciales, races, and vegetative compatibility groups) and evolutionary relationships among members of F. oxysporum species complex (FOSC). It provides updated information on the diversity, structure, regulation, and (a)virulence functions of SIX genes. The improved understanding of roles of SIX in variability and virulence of Fo has significant implication in establishment of molecular framework and techniques for disease management. Finally, the review identifies the gaps in current knowledge and provides insights into potential research landscapes that can be explored to strengthen the understanding of functions of SIX genes.
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Affiliation(s)
| | | | | | | | | | - Rupam Kapoor
- Department of Botany, University of Delhi, New Delhi, India
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de Lamo FJ, Šimkovicová M, Fresno DH, de Groot T, Tintor N, Rep M, Takken FLW. Pattern-triggered immunity restricts host colonization by endophytic fusaria, but does not affect endophyte-mediated resistance. MOLECULAR PLANT PATHOLOGY 2021; 22:204-215. [PMID: 33205901 PMCID: PMC7814963 DOI: 10.1111/mpp.13018] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/21/2020] [Revised: 10/17/2020] [Accepted: 10/21/2020] [Indexed: 05/06/2023]
Abstract
Fusarium oxysporum (Fo) is best known as a host-specific vascular pathogen causing major crop losses. Most Fo strains, however, are root endophytes potentially conferring endophyte-mediated resistance (EMR). EMR is a mechanistically poorly understood root-specific induced resistance response induced by endophytic or nonhost pathogenic Fo strains. Like other types of induced immunity, such as systemic acquired resistance or induced systemic resistance, EMR has been proposed to rely on the activation of the pattern-triggered immunity (PTI) system of the plant. PTI is activated upon recognition of conserved microbe-associated molecular patterns (MAMPs) of invading microbes. Here, we investigated the role of PTI in controlling host colonization by Fo endophytes and their ability to induce EMR to the tomato pathogen Fo f. sp. lycopersici (Fol). Transgenic tomato and Arabidopsis plants expressing the Fo effector gene Avr2 are hypersusceptible to bacterial and fungal infection. Here we show that these plants are PTI-compromised and are nonresponsive to bacterial- (flg22) and fungal- (chitosan) MAMPs. We challenged the PTI-compromised tomato mutants with the EMR-conferring Fo endophyte Fo47, the nonhost pathogen Fom (a melon pathogen), and with Fol. Compared to wild-type plants, Avr2-tomato plants became hypercolonized by Fo47 and Fom. Surprisingly, however, EMR towards Fol, induced by either Fo47 or Fom, was unaffected in these plants. These data show that EMR-based disease resistance is independent from the conventional defence pathways triggered by PTI, but that PTI is involved in restricting host colonization by nonpathogenic Fo isolates.
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Affiliation(s)
- Francisco J. de Lamo
- Molecular Plant PathologyFaculty of ScienceSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamNetherlands
| | - Margarita Šimkovicová
- Molecular Plant PathologyFaculty of ScienceSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamNetherlands
| | - David H. Fresno
- Molecular Plant PathologyFaculty of ScienceSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamNetherlands
| | - Tamara de Groot
- Molecular Plant PathologyFaculty of ScienceSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamNetherlands
| | - Nico Tintor
- Molecular Plant PathologyFaculty of ScienceSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamNetherlands
| | - Martijn Rep
- Molecular Plant PathologyFaculty of ScienceSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamNetherlands
| | - Frank L. W. Takken
- Molecular Plant PathologyFaculty of ScienceSwammerdam Institute for Life SciencesUniversity of AmsterdamAmsterdamNetherlands
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Al-Askar AA, Saber WIA, Ghoneem KM, Hafez EE, Ibrahim AA. Crude Citric Acid of Trichoderma asperellum: Tomato Growth Promotor and Suppressor of Fusarium oxysporum f. sp. lycopersici. PLANTS 2021; 10:plants10020222. [PMID: 33498925 PMCID: PMC7912305 DOI: 10.3390/plants10020222] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 12/18/2020] [Revised: 01/11/2021] [Accepted: 01/20/2021] [Indexed: 12/15/2022]
Abstract
Presently, the bioprocessing of agricultural residues to various bioactive compounds is of great concern, with the potential to be used as plant growth promoters and as a reductive of various diseases. Lycopersiconesculentum, one of the most consumed crops in the human diet, is attacked by Fusarium wilt disease, so the main aim is to biocontrol the pathogen. Several fungal species were isolated from decayed maize stover (MS). Trichodermaasperellum was chosen based on its organic acid productivity and was molecularly identified (GenBank accession number is MW195019). Citric acid (CA) was the major detected organic acid by HPLC. In vitro, CA of T.asperellum at 75% completely repressed the growth of Fusariumoxysporum f. sp. lycopersici (FOL). In vivo, soaking tomato seeds in CA enhanced the seed germination and vigor index. T. asperellum and/or its CA suppressed the wilt disease caused by FOL compared to control. There was a proportional increment of plant growth and yield, as well as improvements in the biochemical parameters (chlorophyll pigments, total phenolic contents and peroxidase, and polyphenol oxidase activities), suggesting targeting both the bioconversion of MS into CA and biological control of FOL.
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Affiliation(s)
- Abdulaziz A. Al-Askar
- Botany and Microbiology Department, Faculty of Science, King Saud University, Riyadh 11451, Saudi Arabia;
| | - WesamEldin I. A. Saber
- Microbial Activity Unit,Microbiology Department, Soils, Water and Environment Research Institute, Agricultural Research Center (ID: 60019332), Giza 12112, Egypt
- Correspondence: (W.I.A.S.); (A.A.I.); Tel.: +020-111-173-1062 (W.I.A.S.); +020-106-667-7539 (A.A.I.)
| | - Khalid M. Ghoneem
- Seed Pathology Research Department, Plant Pathology Research Institute, Agricultural Research Center (ID: 60019332), Giza 12112, Egypt;
| | - Elsayed E. Hafez
- Plant Protection and Biomolecular Diagnosis Department, Arid Lands Cultivation Research Institute, City of Scientific Research and Technological Applications, New Borg El-Arab, Alexandria 21934, Egypt;
| | - Amira A. Ibrahim
- Plant Protection and Biomolecular Diagnosis Department, Arid Lands Cultivation Research Institute, City of Scientific Research and Technological Applications, New Borg El-Arab, Alexandria 21934, Egypt;
- Correspondence: (W.I.A.S.); (A.A.I.); Tel.: +020-111-173-1062 (W.I.A.S.); +020-106-667-7539 (A.A.I.)
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9
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Li J, Fokkens L, Rep M. A single gene in Fusarium oxysporum limits host range. MOLECULAR PLANT PATHOLOGY 2021; 22:108-116. [PMID: 33146465 PMCID: PMC7749751 DOI: 10.1111/mpp.13011] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 07/24/2020] [Accepted: 09/22/2020] [Indexed: 05/07/2023]
Abstract
Fusarium oxysoporum f. sp. radicis-cucumerinum (Forc) is able to cause disease in cucumber, melon, and watermelon, while F. oxysporum f. sp. melonis (Fom) can only infect melon plants. Earlier research showed that mobile chromosomes in Forc and Fom determine the difference in host range between Forc and Fom. By closely comparing these pathogenicity chromosomes combined with RNA-sequencing data, we selected 11 candidate genes that we tested for involvement in the difference in host range between Forc and Fom. One of these candidates is a putative effector gene on the Fom pathogenicity chromosome that has nonidentical homologs on the Forc pathogenicity chromosome. Four independent Forc transformants with this gene from Fom showed strongly reduced or no pathogenicity towards cucumber, while retaining pathogenicity towards melon and watermelon. This suggests that the protein encoded by this gene is recognized by an immune receptor in cucumber plants. This is the first time that a single gene has been demonstrated to determine a difference in host specificity between formae speciales of F. oxysporum.
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Affiliation(s)
- Jiming Li
- Molecular Plant PathologyUniversity of AmsterdamAmsterdamNetherlands
| | - Like Fokkens
- Molecular Plant PathologyUniversity of AmsterdamAmsterdamNetherlands
| | - Martijn Rep
- Molecular Plant PathologyUniversity of AmsterdamAmsterdamNetherlands
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Li J, Cornelissen B, Rep M. Host-specificity factors in plant pathogenic fungi. Fungal Genet Biol 2020; 144:103447. [PMID: 32827756 DOI: 10.1016/j.fgb.2020.103447] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2020] [Revised: 08/14/2020] [Accepted: 08/15/2020] [Indexed: 01/18/2023]
Abstract
Fortunately, no fungus can cause disease on all plant species, and although some plant-pathogenic fungi have quite a broad host range, most are highly limited in the range of plant species or even cultivars that they cause disease in. The mechanisms of host specificity have been extensively studied in many plant-pathogenic fungi, especially in fungal pathogens causing disease on economically important crops. Specifically, genes involved in host specificity have been identified during the last few decades. In this overview, we describe and discuss these host-specificity genes. These genes encode avirulence (Avr) proteins, proteinaceous host-specific toxins or secondary metabolites. We discuss the genomic context of these genes, their expression, polymorphism, horizontal transfer and involvement in pathogenesis.
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Affiliation(s)
- Jiming Li
- Molecular Plant Pathology, University of Amsterdam, Amsterdam 1098 XH, the Netherlands
| | - Ben Cornelissen
- Molecular Plant Pathology, University of Amsterdam, Amsterdam 1098 XH, the Netherlands
| | - Martijn Rep
- Molecular Plant Pathology, University of Amsterdam, Amsterdam 1098 XH, the Netherlands.
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11
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de Vries S, Stukenbrock EH, Rose LE. Rapid evolution in plant-microbe interactions - an evolutionary genomics perspective. THE NEW PHYTOLOGIST 2020; 226:1256-1262. [PMID: 31997351 DOI: 10.1111/nph.16458] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/06/2019] [Accepted: 01/13/2020] [Indexed: 05/22/2023]
Abstract
Access to greater genomic resolution through new sequencing technologies is transforming the field of plant pathology. As scientists embrace these new methods, some overarching patterns and observations come into focus. Evolutionary genomic studies are used to determine not only the origins of pathogen lineages and geographic patterns of genetic diversity, but also to discern how natural selection structures genetic variation across the genome. With greater and greater resolution, we can now pinpoint the targets of selection on a large scale. At multiple levels, crypsis and convergent evolution are evident. Host jumps and shifts may be more pervasive than once believed, and hybridization and horizontal gene transfer (HGT) likely play important roles in the emergence of genetic novelty.
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Affiliation(s)
- Sophie de Vries
- Institute of Population Genetics, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
| | - Eva H Stukenbrock
- Environmental Genomics, Max Planck Institute for Evolutionary Biology, Plön, Germany
- The Botanical Institute, Christian-Albrechts University of Kiel, Am Botanischen Garden 9-11, 24118, Kiel, Germany
| | - Laura E Rose
- Institute of Population Genetics, Heinrich Heine University Düsseldorf, Universitätsstraße 1, 40225, Düsseldorf, Germany
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12
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Duan Y, Qu W, Chang S, Li C, Xu F, Ju M, Zhao R, Wang H, Zhang H, Miao H. Identification of Pathogenicity Groups and Pathogenic Molecular Characterization of Fusarium oxysporum f. sp. sesami in China. PHYTOPATHOLOGY 2020; 110:1093-1104. [PMID: 32065037 DOI: 10.1094/phyto-09-19-0366-r] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Fusarium oxysporum f. sp. sesami is an extremely destructive pathogen, causing sesame Fusarium wilt disease worldwide. To clarify the pathogenicity and the genetic characters of F. oxysporum f. sp. sesami, we systematically investigated 69 F. oxysporum isolates collected from major sesame-growing areas in China. Among these isolates, 54 isolates were pathogenic and 15 were nonpathogenic according to pathogenicity testing on sesame seedlings. For the pathogenic isolates, three F. oxysporum f. sp. sesami pathogenicity groups were defined based on the three differential sesame hosts for the first time. A translation elongation factor 1α gene tree was constructed to determine the genetic diversity of the F. oxysporum isolates but could not separate F. oxysporum f. sp. sesami isolates from the nonpathogenic isolates and other F. oxysporum formae speciales. Ten secreted-in-xylem (SIX) genes (one family of effectors) were identified in F. oxysporum f. sp. sesami isolates by a search with the genome data, and were subsequently screened in the 69 F. oxysporum isolates. Compared with the SIX gene profiles in other F. oxysporum formae speciales, the presence and sequence variations of the SIX gene homologs directly correlated with the specific pathogenicity of F. oxysporum f. sp. sesami toward sesame. Furthermore, eight of these F. oxysporum f. sp. sesami SIX genes were significantly expressed in sesame plants as infection of the F. oxysporum f. sp. sesami isolate. These findings have important significance for understanding the pathogenic basis of F. oxysporum f. sp. sesami isolates, and will contribute to improve the diagnostics to effectively control Fusarium wilt disease in sesame.
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Affiliation(s)
- Yinghui Duan
- Henan Sesame Research Center, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, P. R. China
| | - Wenwen Qu
- Henan Sesame Research Center, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, P. R. China
| | - Shuxian Chang
- Henan Sesame Research Center, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, P. R. China
| | - Chun Li
- Henan Sesame Research Center, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, P. R. China
| | - Fangfang Xu
- Henan Sesame Research Center, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, P. R. China
| | - Ming Ju
- Henan Sesame Research Center, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, P. R. China
| | - Ruihong Zhao
- Henan Sesame Research Center, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, P. R. China
| | - Huili Wang
- Henan Sesame Research Center, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, P. R. China
| | - Haiyang Zhang
- Henan Sesame Research Center, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, P. R. China
| | - Hongmei Miao
- Henan Sesame Research Center, Henan Academy of Agricultural Sciences, Zhengzhou, Henan, 450002, P. R. China
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Constantin ME, Vlieger BV, Takken FLW, Rep M. Diminished Pathogen and Enhanced Endophyte Colonization upon CoInoculation of Endophytic and Pathogenic Fusarium Strains. Microorganisms 2020; 8:E544. [PMID: 32283705 PMCID: PMC7232452 DOI: 10.3390/microorganisms8040544] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/12/2020] [Revised: 04/03/2020] [Accepted: 04/07/2020] [Indexed: 12/23/2022] Open
Abstract
Root colonization by Fusarium oxysporum (Fo) endophytes reduces wilt disease symptoms caused by pathogenic Fo strains. The endophytic strain Fo47, isolated from wilt suppressive soils, reduces Fusarium wilt in various crop species such as tomato, flax, and asparagus. How endophyte-mediated resistance (EMR) against Fusarium wilt is achieved is unclear. Here, nonpathogenic colonization by Fo47 and pathogenic colonization by Fo f.sp. lycopersici (Fol) strains were assessed in tomato roots and stems when inoculated separately or coinoculated. It is shown that Fo47 reduces Fol colonization in stems of both noncultivated and cultivated tomato species. Conversely, Fo47 colonization of coinoculated tomato stems was increased compared to single inoculated plants. Quantitative PCR of fungal colonization of roots (co)inoculated with Fo47 and/or Fol showed that pathogen colonization was drastically reduced when coinoculated with Fo47, compared with single inoculated roots. Endophytic colonization of tomato roots remained unchanged upon coinoculation with Fol. In conclusion, EMR against Fusarium wilt is correlated with a reduction of root and stem colonization by the pathogen. In addition, the endophyte may take advantage of the pathogen-induced suppression of plant defences as it colonizes tomato stems more extensively.
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Affiliation(s)
| | | | | | - Martijn Rep
- Molecular Plant Pathology, Faculty of Science, Swammerdam Institute for Life Sciences, University of Amsterdam, 1098 XH Amsterdam, The Netherlands; (M.E.C.); (F.L.W.T.)
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14
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Kim JH, Castroverde CDM. Diversity, Function and Regulation of Cell Surface and Intracellular Immune Receptors in Solanaceae. PLANTS 2020; 9:plants9040434. [PMID: 32244634 PMCID: PMC7238418 DOI: 10.3390/plants9040434] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/26/2020] [Revised: 03/14/2020] [Accepted: 03/23/2020] [Indexed: 12/29/2022]
Abstract
The first layer of the plant immune system comprises plasma membrane-localized receptor proteins and intracellular receptors of the nucleotide-binding leucine-rich repeat protein superfamily. Together, these immune receptors act as a network of surveillance machines in recognizing extracellular and intracellular pathogen invasion-derived molecules, ranging from conserved structural epitopes to virulence-promoting effectors. Successful pathogen recognition leads to physiological and molecular changes in the host plants, which are critical for counteracting and defending against biotic attack. A breadth of significant insights and conceptual advances have been derived from decades of research in various model plant species regarding the structural complexity, functional diversity, and regulatory mechanisms of these plant immune receptors. In this article, we review the current state-of-the-art of how these host surveillance proteins function and how they are regulated. We will focus on the latest progress made in plant species belonging to the Solanaceae family, because of their tremendous importance as model organisms and agriculturally valuable crops.
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Affiliation(s)
- Jong Hum Kim
- Department of Energy Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Howard Hughes Medical Institute, Michigan State University, East Lansing, MI 48824, USA
- Correspondence: (J.H.K.); (C.D.M.C.)
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15
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Taylor A, Armitage AD, Handy C, Jackson AC, Hulin MT, Harrison RJ, Clarkson JP. Basal Rot of Narcissus: Understanding Pathogenicity in Fusarium oxysporum f. sp. narcissi. Front Microbiol 2019; 10:2905. [PMID: 31921077 PMCID: PMC6930931 DOI: 10.3389/fmicb.2019.02905] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2019] [Accepted: 12/02/2019] [Indexed: 12/21/2022] Open
Abstract
Fusarium oxysporum is a globally distributed soilborne fungal pathogen causing root rots, bulb rots, crown rots and vascular wilts on a range of horticultural plants. Pathogenic F. oxysporum isolates are highly host specific and are classified as formae speciales. Narcissus is an important ornamental crop and both the quality and yield of flowers and bulbs can be severely affected by a basal rot caused by F. oxysporum f. sp. narcissi (FON); 154 Fusarium isolates were obtained from different locations and Narcissus cultivars in the United Kingdom, representing a valuable resource. A subset of 30 F. oxysporum isolates were all found to be pathogenic and were therefore identified as FON. Molecular characterisation of isolates through sequencing of three housekeeping genes, suggested a monophyletic origin with little divergence. PCR detection of 14 Secreted in Xylem (SIX) genes, previously shown to be associated with pathogenicity in other F. oxysporum f. spp., revealed different complements of SIX7, SIX9, SIX10, SIX12 and SIX13 within FON isolates which may suggest a race structure. SIX gene sequences were unique to FON and SIX10 was present in all isolates, allowing for molecular identification of FON for the first time. The genome of a highly pathogenic isolate was sequenced and lineage specific (LS) regions identified which harboured putative effectors including the SIX genes. Real-time RT-PCR, showed that SIX genes and selected putative effectors were expressed in planta with many significantly upregulated during infection. This is the first study to characterise molecular variation in FON and provide an analysis of the FON genome. Identification of expressed genes potentially associated with virulence provides the basis for future functional studies and new targets for molecular diagnostics.
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Affiliation(s)
- Andrew Taylor
- Warwick Crop Centre, School of Life Sciences, University of Warwick, Warwick, United Kingdom
| | | | - Claire Handy
- Warwick Crop Centre, School of Life Sciences, University of Warwick, Warwick, United Kingdom
| | - Alison C Jackson
- Warwick Crop Centre, School of Life Sciences, University of Warwick, Warwick, United Kingdom
| | | | | | - John P Clarkson
- Warwick Crop Centre, School of Life Sciences, University of Warwick, Warwick, United Kingdom
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16
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Zhou D, Jing T, Chen Y, Wang F, Qi D, Feng R, Xie J, Li H. Deciphering microbial diversity associated with Fusarium wilt-diseased and disease-free banana rhizosphere soil. BMC Microbiol 2019; 19:161. [PMID: 31299891 PMCID: PMC6626388 DOI: 10.1186/s12866-019-1531-6] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 06/26/2019] [Indexed: 11/18/2022] Open
Abstract
Background Fusarium wilt of banana (Musa spp.) caused by the fungal pathogen Fusarium oxysporum f. sp. cubense (Foc) is a typical soilborne disease, that severely devastates the banana industry worldwide, and soil microbial diversity is closely related to the spread of Fusarium wilt. To understand the relationship between microbial species and Fusarium wilt, it is important to understand the microbial diversity of the Fusarium wilt-diseased and disease-free soils from banana fields. Results Based on sequencing analysis of the bacterial 16S rRNA genes and fungal internal transcribed spacer (ITS) sequences, Foc abundance, fungal or bacterial richness and diversity were higher in the diseased soils than in the disease-free soils. Although Ascomycota and Zygomycota were the most abundant fungi phyla in all soil samples, Ascomycota abundance was significantly reduced in the disease-free soils. Mortierella (36.64%) was predominant in the disease-free soils. Regarding bacterial phyla, Proteobacteria, Acidobacteria, Chloroflexi, Firmicutes, Actinobacteria, Gemmatimonadetes, Bacteroidetes, Nitrospirae, Verrucomicrobia and Planctomycetes were dominant phyla in all soil samples. In particular, Firmicutes contributed 16.20% of the total abundance of disease-free soils. At the bacterial genus level, Bacillus, Lactococcus and Pseudomonas were abundant in disease-free soils with abundances of 8.20, 5.81 and 2.71%, respectively; lower abundances, of 4.12, 2.35 and 1.36%, respectively, were found in diseased soils. The distribution characteristics of fungal and bacterial genera may contribute to the abundance decrease of Foc in the disease-free soils. Conclusion Unique distributions of bacteria and fungi were observed in the diseased and disease-free soil samples from banana fields. These specific genera are useful for constructing a healthy microbial community structure of soil.
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Affiliation(s)
- Dengbo Zhou
- Institute of Tropical Bioscience and Biotechnology, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China
| | - Tao Jing
- Haikou Experimental Station, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China
| | - Yufeng Chen
- Institute of Tropical Bioscience and Biotechnology, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China
| | - Fei Wang
- Institute of Tropical Bioscience and Biotechnology, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China
| | - Dengfeng Qi
- Institute of Tropical Bioscience and Biotechnology, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China
| | - Renjun Feng
- Institute of Tropical Bioscience and Biotechnology, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China
| | - Jianghui Xie
- Institute of Tropical Bioscience and Biotechnology, China Academy of Tropical Agricultural Sciences, Haikou, Hainan, China.
| | - Huaping Li
- Guangdong Province Key Laboratory of Microbial Signals and Disease Control, College of Agriculture, South China Agricultural University, Guangzhou, Guangdong, China.
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Srinivas C, Nirmala Devi D, Narasimha Murthy K, Mohan CD, Lakshmeesha TR, Singh B, Kalagatur NK, Niranjana SR, Hashem A, Alqarawi AA, Tabassum B, Abd Allah EF, Chandra Nayaka S. Fusarium oxysporum f. sp. lycopersici causal agent of vascular wilt disease of tomato: Biology to diversity- A review. Saudi J Biol Sci 2019; 26:1315-1324. [PMID: 31762590 PMCID: PMC6864208 DOI: 10.1016/j.sjbs.2019.06.002] [Citation(s) in RCA: 76] [Impact Index Per Article: 15.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2019] [Revised: 06/01/2019] [Accepted: 06/02/2019] [Indexed: 01/01/2023] Open
Abstract
Tomato (Lycopersicon esculentum) is one of the widely grown vegetables worldwide. Fusarium oxysporum f. sp. lycopersici (FOL) is the significant contributory pathogen of tomato vascular wilt. The initial symptoms of the disease appear in the lower leaves gradually, trail by wilting of the plants. It has been reported that FOL penetrates the tomato plant, colonizing and leaving the vascular tissue dark brown, and this discoloration extends to the apex, leading to the plants wilting, collapsing and dying. Therefore, it has been widely accepted that wilting caused by this fungus is the result of a combination of various physiological activities, including the accumulation of fungal mycelia in and around xylem, mycotoxin production, inactivation of host defense, and the production of tyloses; however, wilting symptoms are variable. Therefore, the selection of molecular markers may be a more effective means of screening tomato races. Several studies on the detection of FOL have been carried out and have suggested the potency of the technique for diagnosing FOL. This review focuses on biology and variability of FOL, understanding and presenting a holistic picture of the vascular wilt disease of tomato in relation to disease model, biology, virulence. We conclude that genomic and proteomic approachesare greater tools for identification of informative candidates involved in pathogenicity, which can be considered as one of the approaches in managing the disease.
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Affiliation(s)
- C Srinivas
- Department of Studies in Microbiology and Biotechnology, Bangalore University, Bengaluru, Karnataka, India
| | - D Nirmala Devi
- Department of Microbiology, Ramaiah College of Arts, Science and Commerce, Bengaluru, Karnataka, India
| | - K Narasimha Murthy
- Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore,India
| | | | - T R Lakshmeesha
- Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore,India
| | | | - Naveen Kumar Kalagatur
- Department of Immunology and Toxicology, DRDO-BU-Centre for Life Sciences, Coimbatore, India
| | - S R Niranjana
- Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore,India
| | - Abeer Hashem
- Plant Production Department, College of Food and Agriculture Science, King SaudUniversity, P.O. Box 2460, Riyadh 11451, Saudi Arabia
| | - Abdulaziz A Alqarawi
- Plant Production Department, College of Food and Agriculture Science, King SaudUniversity, P.O. Box 2460, Riyadh 11451, Saudi Arabia
| | - Baby Tabassum
- Toxicology Laboratory, Department of Zoology, Govt. Raza P.G. College Rampur, 244901 U.P., India
| | - Elsayed Fathi Abd Allah
- Plant Production Department, College of Food and Agriculture Science, King SaudUniversity, P.O. Box 2460, Riyadh 11451, Saudi Arabia
| | - S Chandra Nayaka
- Department of Studies in Biotechnology, University of Mysore, Manasagangotri, Mysore,India
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18
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Lombard L, Sandoval-Denis M, Lamprecht S, Crous P. Epitypification of Fusarium oxysporum - clearing the taxonomic chaos. PERSOONIA 2018; 43:1-47. [PMID: 32214496 PMCID: PMC7085860 DOI: 10.3767/persoonia.2019.43.01] [Citation(s) in RCA: 68] [Impact Index Per Article: 11.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 10/19/2018] [Indexed: 01/06/2023]
Abstract
Fusarium oxysporum is the most economically important and commonly encountered species of Fusarium. This soil-borne fungus is known to harbour both pathogenic (plant, animal and human) and non-pathogenic strains. However, in its current concept F. oxysporum is a species complex consisting of numerous cryptic species. Identification and naming these cryptic species is complicated by multiple subspecific classification systems and the lack of living ex-type material to serve as basic reference point for phylogenetic inference. Therefore, to advance and stabilise the taxonomic position of F. oxysporum as a species and allow naming of the multiple cryptic species recognised in this species complex, an epitype is designated for F. oxysporum. Using multi-locus phylogenetic inference and subtle morphological differences with the newly established epitype of F. oxysporum as reference point, 15 cryptic taxa are resolved in this study and described as species.
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Affiliation(s)
- L. Lombard
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
| | - M. Sandoval-Denis
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
- Faculty of Natural and Agricultural Sciences, Department of Plant Sciences, University of the Free State, P.O. Box 339, Bloemfontein 9300, South Africa
| | - S.C. Lamprecht
- ARC-Plant Health and Protection, Private Bag X5017, Stellenbosch, 7599, Western Cape, South Africa
| | - P.W. Crous
- Westerdijk Fungal Biodiversity Institute, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands
- Faculty of Natural and Agricultural Sciences, Department of Plant Sciences, University of the Free State, P.O. Box 339, Bloemfontein 9300, South Africa
- Wageningen University and Research Centre (WUR), Laboratory of Phytopathology, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands
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19
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Armitage AD, Taylor A, Sobczyk MK, Baxter L, Greenfield BPJ, Bates HJ, Wilson F, Jackson AC, Ott S, Harrison RJ, Clarkson JP. Characterisation of pathogen-specific regions and novel effector candidates in Fusarium oxysporum f. sp. cepae. Sci Rep 2018; 8:13530. [PMID: 30202022 PMCID: PMC6131394 DOI: 10.1038/s41598-018-30335-7] [Citation(s) in RCA: 49] [Impact Index Per Article: 8.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2017] [Accepted: 07/20/2018] [Indexed: 12/21/2022] Open
Abstract
A reference-quality assembly of Fusarium oxysporum f. sp. cepae (Foc), the causative agent of onion basal rot has been generated along with genomes of additional pathogenic and non-pathogenic isolates of onion. Phylogenetic analysis confirmed a single origin of the Foc pathogenic lineage. Genome alignments with other F. oxysporum ff. spp. and non pathogens revealed high levels of syntenic conservation of core chromosomes but little synteny between lineage specific (LS) chromosomes. Four LS contigs in Foc totaling 3.9 Mb were designated as pathogen-specific (PS). A two-fold increase in segmental duplication events was observed between LS regions of the genome compared to within core regions or from LS regions to the core. RNA-seq expression studies identified candidate effectors expressed in planta, consisting of both known effector homologs and novel candidates. FTF1 and a subset of other transcription factors implicated in regulation of effector expression were found to be expressed in planta.
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Affiliation(s)
| | - Andrew Taylor
- Warwick Crop Centre, School of Life Sciences, University of Warwick, Wellesbourne, Warwick, CV35 9EF, UK
| | | | - Laura Baxter
- Warwick Crop Centre, School of Life Sciences, University of Warwick, Wellesbourne, Warwick, CV35 9EF, UK
| | | | - Helen J Bates
- NIAB-EMR, New Road, East Malling, Kent, ME19 6BJ, UK
| | - Fiona Wilson
- NIAB-EMR, New Road, East Malling, Kent, ME19 6BJ, UK
| | - Alison C Jackson
- Warwick Crop Centre, School of Life Sciences, University of Warwick, Wellesbourne, Warwick, CV35 9EF, UK
| | - Sascha Ott
- Department of Computer Science, University of Warwick, CV4 7AL, Warwick, UK
| | | | - John P Clarkson
- Warwick Crop Centre, School of Life Sciences, University of Warwick, Wellesbourne, Warwick, CV35 9EF, UK
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20
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Di X, Cao L, Hughes RK, Tintor N, Banfield MJ, Takken FLW. Structure-function analysis of the Fusarium oxysporum Avr2 effector allows uncoupling of its immune-suppressing activity from recognition. THE NEW PHYTOLOGIST 2017; 216:897-914. [PMID: 28857169 PMCID: PMC5659127 DOI: 10.1111/nph.14733] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/17/2017] [Accepted: 07/03/2017] [Indexed: 05/09/2023]
Abstract
Plant pathogens employ effector proteins to manipulate their hosts. Fusarium oxysporum f. sp. lycopersici (Fol), the causal agent of tomato wilt disease, produces effector protein Avr2. Besides being a virulence factor, Avr2 triggers immunity in I-2 carrying tomato (Solanum lycopersicum). Fol strains that evade I-2 recognition carry point mutations in Avr2 (e.g. Avr2R45H ), but retain full virulence. Here we investigate the virulence function of Avr2 and determine its crystal structure. Transgenic tomato and Arabidopsis expressing either wild-type ΔspAvr2 (deleted signal-peptide) or the ΔspAvr2R45H variant become hypersusceptible to fungal, and even bacterial infections, suggesting that Avr2 targets a conserved defense mechanism. Indeed, Avr2 transgenic plants are attenuated in immunity-related readouts, including flg22-induced growth inhibition, ROS production and callose deposition. The crystal structure of Avr2 reveals that the protein shares intriguing structural similarity to ToxA from the wheat pathogen Pyrenophora tritici-repentis and to TRAF proteins. The I-2 resistance-breaking Avr2V41M , Avr2R45H and Avr2R46P variants cluster on a surface-presented loop. Structure-guided mutagenesis enabled uncoupling of virulence from I-2-mediated recognition. We conclude that I-2-mediated recognition is not based on monitoring Avr2 virulence activity, which includes suppression of immune responses via an evolutionarily conserved effector target, but by recognition of a distinct epitope.
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Affiliation(s)
- Xiaotang Di
- Molecular Plant PathologySILSUniversity of AmsterdamPO Box 942151090 GEAmsterdamthe Netherlands
| | - Lingxue Cao
- Molecular Plant PathologySILSUniversity of AmsterdamPO Box 942151090 GEAmsterdamthe Netherlands
| | - Richard K. Hughes
- Department of Biological ChemistryJohn Innes CentreNorwich Research ParkNorwichNR4 7UHUK
| | - Nico Tintor
- Molecular Plant PathologySILSUniversity of AmsterdamPO Box 942151090 GEAmsterdamthe Netherlands
| | - Mark J. Banfield
- Department of Biological ChemistryJohn Innes CentreNorwich Research ParkNorwichNR4 7UHUK
| | - Frank L. W. Takken
- Molecular Plant PathologySILSUniversity of AmsterdamPO Box 942151090 GEAmsterdamthe Netherlands
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21
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Ayukawa Y, Hanyuda S, Fujita N, Komatsu K, Arie T. Novel loop-mediated isothermal amplification (LAMP) assay with a universal QProbe can detect SNPs determining races in plant pathogenic fungi. Sci Rep 2017; 7:4253. [PMID: 28652587 PMCID: PMC5484703 DOI: 10.1038/s41598-017-04084-y] [Citation(s) in RCA: 23] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2017] [Accepted: 05/09/2017] [Indexed: 12/13/2022] Open
Abstract
Tomato wilt pathogen Fusarium oxysporum f. sp. lycopersici (Fol) is grouped into three races based on their pathogenicity to different host cultivars. Rapid detection and discrimination of Fol races in field soils is important to prevent tomato wilt disease. Although five types of point mutations in secreted in xylem 3 (SIX3) gene, which are characteristic of race 3, have been reported as a molecular marker for the race, detection of these point mutations is laborious. The aim of this study is to develop a rapid and accurate method for the detection of point mutations in SIX3 of Fol. Loop-mediated isothermal amplification (LAMP) of SIX3 gene with the universal QProbe as well as two joint DNAs followed by annealing curve analysis allowed us to specifically detect Fol and discriminate race 3 among other races in about one hour. Our developed method is applicable for detection of races of other plant pathogenic fungi as well as their pesticide-resistant mutants that arise through point mutations in a particular gene.
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Affiliation(s)
- Yu Ayukawa
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology (TUAT), Fuchu, Tokyo, 183-8509, Japan
- Laboratory of Plant Pathology, Graduate School of Agriculture, Tokyo University of Agriculture and Technology (TUAT), Fuchu, Tokyo, 183-8509, Japan
| | - Saeri Hanyuda
- Laboratory of Plant Pathology, Graduate School of Agriculture, Tokyo University of Agriculture and Technology (TUAT), Fuchu, Tokyo, 183-8509, Japan
| | - Naoko Fujita
- Laboratory of Plant Pathology, Graduate School of Agriculture, Tokyo University of Agriculture and Technology (TUAT), Fuchu, Tokyo, 183-8509, Japan
| | - Ken Komatsu
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology (TUAT), Fuchu, Tokyo, 183-8509, Japan.
- Laboratory of Plant Pathology, Graduate School of Agriculture, Tokyo University of Agriculture and Technology (TUAT), Fuchu, Tokyo, 183-8509, Japan.
| | - Tsutomu Arie
- United Graduate School of Agricultural Science, Tokyo University of Agriculture and Technology (TUAT), Fuchu, Tokyo, 183-8509, Japan
- Laboratory of Plant Pathology, Graduate School of Agriculture, Tokyo University of Agriculture and Technology (TUAT), Fuchu, Tokyo, 183-8509, Japan
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22
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Chellapan BV, van Dam P, Rep M, Cornelissen BJC, Fokkens L. Non-canonical Helitrons in Fusarium oxysporum. Mob DNA 2016; 7:27. [PMID: 27990178 PMCID: PMC5148889 DOI: 10.1186/s13100-016-0083-7] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2016] [Accepted: 12/03/2016] [Indexed: 01/18/2023] Open
Abstract
Background Helitrons are eukaryotic rolling circle transposable elements that can have a large impact on host genomes due to their copy-number and their ability to capture and copy genes and regulatory elements. They occur widely in plants and animals, and have thus far been relatively little investigated in fungi. Results Here, we comprehensively survey Helitrons in several completely sequenced genomes representing the F. oxysporum species complex (FOSC). We thoroughly characterize 5 different Helitron subgroups and determine their impact on genome evolution and assembly in this species complex. FOSC Helitrons resemble members of the Helitron2 variant that includes Helentrons and DINEs. The fact that some Helitrons appeared to be still active in FOSC provided the opportunity to determine whether Helitrons occur as a circular intermediate in FOSC. We present experimental evidence suggesting that at least one Helitron subgroup occurs with joined ends, suggesting a circular intermediate. We extend our analyses to other Pezizomycotina and find that most fungal Helitrons we identified group phylogenetically with Helitron2 and probably have similar characteristics. Conclusions FOSC genomes harbour non-canonical Helitrons that are characterized by asymmetric terminal inverted repeats, show hallmarks of recent activity and likely transpose via a circular intermediate. Bioinformatic analyses indicate that they are representative of a large reservoir of fungal Helitrons that thus far has not been characterized. Electronic supplementary material The online version of this article (doi:10.1186/s13100-016-0083-7) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Biju Vadakkemukadiyil Chellapan
- Department of Computational Biology and Bioinformatics, University of Kerala, Karyavattom Campus, Karyavattom PO, Trivandrum, Kerala India ; Molecular Plant Pathology, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, P.O. Box 94215, 1090 Amsterdam, GE The Netherlands
| | - Peter van Dam
- Molecular Plant Pathology, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, P.O. Box 94215, 1090 Amsterdam, GE The Netherlands
| | - Martijn Rep
- Molecular Plant Pathology, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, P.O. Box 94215, 1090 Amsterdam, GE The Netherlands
| | - Ben J C Cornelissen
- Molecular Plant Pathology, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, P.O. Box 94215, 1090 Amsterdam, GE The Netherlands
| | - Like Fokkens
- Molecular Plant Pathology, Swammerdam Institute for Life Sciences, Faculty of Science, University of Amsterdam, P.O. Box 94215, 1090 Amsterdam, GE The Netherlands
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