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Bartholomew HP, Reynoso G, Thomas BJ, Mullins CM, Smith C, Gentzel IN, Giese LA, Mackey D, Stevens AM. The Transcription Factor Lrp of Pantoea stewartii subsp. stewartii Controls Capsule Production, Motility, and Virulence Important for in planta Growth. Front Microbiol 2022; 12:806504. [PMID: 35237242 PMCID: PMC8882988 DOI: 10.3389/fmicb.2021.806504] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/31/2021] [Accepted: 12/17/2021] [Indexed: 11/13/2022] Open
Abstract
The bacterial phytopathogen Pantoea stewartii subsp. stewartii causes leaf blight and Stewart's wilt disease in susceptible corn varieties. A previous RNA-Seq study examined P. stewartii gene expression patterns during late-stage infection in the xylem, and a Tn-Seq study using a P. stewartii mutant library revealed genes essential for colonization of the xylem. Based on these findings, strains with in-frame chromosomal deletions in the genes encoding seven transcription factors (NsrR, IscR, Nac, Lrp, DSJ_00125, DSJ_03645, and DSJ_18135) and one hypothetical protein (DSJ_21690) were constructed to further evaluate the role of the encoded gene products during in vitro and in planta growth. Assays for capsule production and motility indicate that Lrp plays a role in regulating these two key physiological outputs in vitro. Single infections of each deletion strain into the xylem of corn seedlings determined that Lrp plays a significant role in P. stewartii virulence. In planta xylem competition assays between co-inoculated deletion and the corresponding complementation or wild-type strains as well as in vitro growth curves determined that Lrp controls functions important for P. stewartii colonization and growth in corn plants, whereas IscR may have a more generalized impact on growth. Defining the role of essential transcription factors, such as Lrp, during in planta growth will enable modeling of key components of the P. stewartii regulatory network utilized during growth in corn plants.
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Affiliation(s)
| | - Guadalupe Reynoso
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Brandi J. Thomas
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Chase M. Mullins
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Chastyn Smith
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, United States
| | - Irene N. Gentzel
- Department of Horticulture & Crop Science, The Ohio State University, Columbus, OH, United States
| | - Laura A. Giese
- Department of Horticulture & Crop Science, The Ohio State University, Columbus, OH, United States
| | - David Mackey
- Department of Horticulture & Crop Science, The Ohio State University, Columbus, OH, United States
- Department of Molecular Genetics and Center for Applied Plant Sciences, The Ohio State University, Columbus, OH, United States
| | - Ann M. Stevens
- Department of Biological Sciences, Virginia Tech, Blacksburg, VA, United States
- Center for Emerging, Zoonotic and Arthropod-Borne Pathogens, Virginia Tech, Blacksburg, VA, United States
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2
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Catara V, Cubero J, Pothier JF, Bosis E, Bragard C, Đermić E, Holeva MC, Jacques MA, Petter F, Pruvost O, Robène I, Studholme DJ, Tavares F, Vicente JG, Koebnik R, Costa J. Trends in Molecular Diagnosis and Diversity Studies for Phytosanitary Regulated Xanthomonas. Microorganisms 2021; 9:862. [PMID: 33923763 PMCID: PMC8073235 DOI: 10.3390/microorganisms9040862] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/31/2021] [Revised: 04/10/2021] [Accepted: 04/12/2021] [Indexed: 11/17/2022] Open
Abstract
Bacteria in the genus Xanthomonas infect a wide range of crops and wild plants, with most species responsible for plant diseases that have a global economic and environmental impact on the seed, plant, and food trade. Infections by Xanthomonas spp. cause a wide variety of non-specific symptoms, making their identification difficult. The coexistence of phylogenetically close strains, but drastically different in their phenotype, poses an added challenge to diagnosis. Data on future climate change scenarios predict an increase in the severity of epidemics and a geographical expansion of pathogens, increasing pressure on plant health services. In this context, the effectiveness of integrated disease management strategies strongly depends on the availability of rapid, sensitive, and specific diagnostic methods. The accumulation of genomic information in recent years has facilitated the identification of new DNA markers, a cornerstone for the development of more sensitive and specific methods. Nevertheless, the challenges that the taxonomic complexity of this genus represents in terms of diagnosis together with the fact that within the same bacterial species, groups of strains may interact with distinct host species demonstrate that there is still a long way to go. In this review, we describe and discuss the current molecular-based methods for the diagnosis and detection of regulated Xanthomonas, taxonomic and diversity studies in Xanthomonas and genomic approaches for molecular diagnosis.
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Affiliation(s)
- Vittoria Catara
- Department of Agriculture, Food and Environment, University of Catania, 95125 Catania, Italy
| | - Jaime Cubero
- National Institute for Agricultural and Food Research and Technology (INIA), 28002 Madrid, Spain;
| | - Joël F. Pothier
- Environmental Genomics and Systems Biology Research Group, Institute for Natural Resource Sciences, Zurich University of Applied Sciences (ZHAW), 8820 Wädenswil, Switzerland;
| | - Eran Bosis
- Department of Biotechnology Engineering, ORT Braude College of Engineering, Karmiel 2161002, Israel;
| | - Claude Bragard
- UCLouvain, Earth & Life Institute, Applied Microbiology, 1348 Louvain-la-Neuve, Belgium;
| | - Edyta Đermić
- Department of Plant Pathology, Faculty of Agriculture, University of Zagreb, 10000 Zagreb, Croatia;
| | - Maria C. Holeva
- Benaki Phytopathological Institute, Scientific Directorate of Phytopathology, Laboratory of Bacteriology, GR-14561 Kifissia, Greece;
| | - Marie-Agnès Jacques
- IRHS, INRA, AGROCAMPUS-Ouest, Univ Angers, SFR 4207 QUASAV, 49071 Beaucouzé, France;
| | - Francoise Petter
- European and Mediterranean Plant Protection Organization (EPPO/OEPP), 75011 Paris, France;
| | - Olivier Pruvost
- CIRAD, UMR PVBMT, F-97410 Saint Pierre, La Réunion, France; (O.P.); (I.R.)
| | - Isabelle Robène
- CIRAD, UMR PVBMT, F-97410 Saint Pierre, La Réunion, France; (O.P.); (I.R.)
| | | | - Fernando Tavares
- CIBIO—Centro de Investigação em Biodiversidade e Recursos Genéticos, InBIO-Laboratório Associado, Universidade do Porto, 4485-661 Vairão, Portugal; or
- FCUP-Faculdade de Ciências, Departamento de Biologia, Universidade do Porto, Rua do Campo Alegre, 4169-007 Porto, Portugal
| | | | - Ralf Koebnik
- Plant Health Institute of Montpellier (PHIM), Univ Montpellier, Cirad, INRAe, Institut Agro, IRD, 34398 Montpellier, France;
| | - Joana Costa
- Centre for Functional Ecology-Science for People & the Planet, Department of Life Sciences, University of Coimbra, 300-456 Coimbra, Portugal
- Laboratory for Phytopathology, Instituto Pedro Nunes, 3030-199 Coimbra, Portugal
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3
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Jeong K, Muñoz-Bodnar A, Arias Rojas N, Poulin L, Rodriguez-R LM, Gagnevin L, Vernière C, Pruvost O, Koebnik R. CRISPR elements provide a new framework for the genealogy of the citrus canker pathogen Xanthomonas citri pv. citri. BMC Genomics 2019; 20:917. [PMID: 31791238 PMCID: PMC6889575 DOI: 10.1186/s12864-019-6267-z] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2019] [Accepted: 11/06/2019] [Indexed: 12/26/2022] Open
Abstract
Background Xanthomonads are an important clade of Gram-negative bacteria infecting a plethora of economically important host plants, including citrus. Knowledge about the pathogen’s diversity and population structure are prerequisite for epidemiological surveillance and efficient disease management. Rapidly evolving genetic loci, such as Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR), are of special interest to develop new molecular typing tools. Results We analyzed CRISPR loci of 56 Xanthomonas citri pv. citri strains of world-wide origin, a regulated pathogen causing Asiatic citrus canker in several regions of the world. With one exception, 23 unique sequences built up the repertoire of spacers, suggesting that this set of strains originated from a common ancestor that already harbored these 23 spacers. One isolate originating from Pakistan contained a string of 14 additional, probably more recently acquired spacers indicating that this genetic lineage has or had until recently the capacity to acquire new spacers. Comparison of CRISPR arrays with previously obtained molecular typing data, such as amplified fragment length polymorphisms (AFLP), variable-number of tandem-repeats (VNTR) and genome-wide single-nucleotide polymorphisms (SNP), demonstrated that these methods reveal similar evolutionary trajectories. Notably, genome analyses allowed to generate a model for CRISPR array evolution in X. citri pv. citri, which provides a new framework for the genealogy of the citrus canker pathogen. Conclusions CRISPR-based typing will further improve the accuracy of the genetic identification of X. citri pv. citri outbreak strains in molecular epidemiology analyses, especially when used concomitantly with another genotyping method.
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Affiliation(s)
- Kwanho Jeong
- IRD, Cirad, Université de Montpellier, IPME, Montpellier, France
| | - Alejandra Muñoz-Bodnar
- IRD, Cirad, Université de Montpellier, IPME, Montpellier, France.,Present address: Current address: Department of Plant Pathology, University of Florida, Gainesville, FL, 32611, USA
| | | | - Lucie Poulin
- IRD, Cirad, Université de Montpellier, IPME, Montpellier, France.,Present address: Laboratoire de Biologie et de Pathologie Végétales, Université de Nantes, Nantes, France
| | - Luis Miguel Rodriguez-R
- IRD, Cirad, Université de Montpellier, IPME, Montpellier, France.,Present address: Department of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA, 30332, USA
| | - Lionel Gagnevin
- IRD, Cirad, Université de Montpellier, IPME, Montpellier, France.,CIRAD, UMR PVBMT, 97410, Saint Pierre, La Réunion, France
| | - Christian Vernière
- CIRAD, UMR PVBMT, 97410, Saint Pierre, La Réunion, France.,CIRAD, UMR BGPI, 34398, Montpellier, France
| | | | - Ralf Koebnik
- IRD, Cirad, Université de Montpellier, IPME, Montpellier, France.
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Conforte VP, Malamud F, Yaryura PM, Toum Terrones L, Torres PS, De Pino V, Chazarreta CN, Gudesblat GE, Castagnaro AP, R. Marano M, Vojnov AA. The histone-like protein HupB influences biofilm formation and virulence in Xanthomonas citri ssp. citri through the regulation of flagellar biosynthesis. MOLECULAR PLANT PATHOLOGY 2019; 20:589-598. [PMID: 30537413 PMCID: PMC6637892 DOI: 10.1111/mpp.12777] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Citrus canker is an important disease of citrus, whose causal agent is the bacterium Xanthomonas citri ssp. citri (Xcc). In previous studies, we found a group of Xcc mutants, generated by the insertion of the Tn5 transposon, which showed impaired ability to attach to an abiotic substrate. One of these mutants carries the Tn5 insertion in hupB, a gene encoding a bacterial histone-like protein, homologue to the β-subunit of the Heat-Unstable (HU) nucleoid protein of Escherichia coli. These types of protein are necessary to maintain the bacterial nucleoid organization and the global regulation of gene expression. Here, we characterized the influence of the mutation in hupB regarding Xcc biofilm formation and virulence. The mutant strain hupB was incapable of swimming in soft agar, whereas its complemented strain partially recovered this phenotype. Electron microscope imaging revealed that impaired motility of hupB was a consequence of the absence of the flagellum. Comparison of the expression of flagellar genes between the wild-type strain and hupB showed that the mutant exhibited decreased expression of fliC (encoding flagellin). The hupB mutant also displayed reduced virulence compared with the wild-type strain when they were used to infect Citrus lemon plants using different infection methods. Our results therefore show that the histone-like protein HupB plays an essential role in the pathogenesis of Xcc through the regulation of biofilm formation and biosynthesis of the flagellum.
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Affiliation(s)
- Valeria P. Conforte
- Instituto de Ciencia y Tecnología Dr. César Milstein, Fundación Pablo Cassará, CONICETSaladillo 2468Ciudad de Buenos AiresC1440FFXArgentina
| | - Florencia Malamud
- Instituto de Investigaciones Biotecnológicas, Universidad Nacional de San MartínCampus Migueletes, 25 de Mayo y FranciaGeneral San MartínB1650HMN Provincia de Buenos AiresArgentina
| | - Pablo M. Yaryura
- Centro de Investigaciones y Transferencia de Villa María CONICETUniversidad de Villa MaríaCarlos Pellegrini 211Villa María, X5900FSECórdobaArgentina
| | - Laila Toum Terrones
- Departamento de FisiologíaBiología Molecular y Celular, Instituto de Biodiversidad y Biología Experimental y Aplicada, CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos AiresIntendente Güiraldes 2160Buenos AiresC1428EGAArgentina
| | - Pablo S. Torres
- Instituto de Ciencia y Tecnología Dr. César Milstein, Fundación Pablo Cassará, CONICETSaladillo 2468Ciudad de Buenos AiresC1440FFXArgentina
| | - Verónica De Pino
- Instituto de Ciencia y Tecnología Dr. César Milstein, Fundación Pablo Cassará, CONICETSaladillo 2468Ciudad de Buenos AiresC1440FFXArgentina
| | - Cristian N. Chazarreta
- Instituto de Ciencia y Tecnología Dr. César Milstein, Fundación Pablo Cassará, CONICETSaladillo 2468Ciudad de Buenos AiresC1440FFXArgentina
| | - Gustavo E. Gudesblat
- Instituto de Tecnología Agroindustrial del Noroeste Argentino (ITANOA), Estación Experimental Agroindustrial Obispo Colombres (EEAOC), Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET)Av. William Cross 3150Las TalitasC.P. T4101XACTucumánArgentina
| | - Atilio P. Castagnaro
- Departamento de FisiologíaBiología Molecular y Celular, Instituto de Biodiversidad y Biología Experimental y Aplicada, CONICET, Facultad de Ciencias Exactas y Naturales, Universidad de Buenos AiresIntendente Güiraldes 2160Buenos AiresC1428EGAArgentina
| | - María R. Marano
- Instituto de Biología Molecular y Celular de Rosario, Departamento de Microbiología, Facultad de Ciencias, Bioquímicas y FarmacéuticasUniversidad Nacional de RosarioSuipacha 531RosarioS2002LRKSanta FéArgentina
| | - Adrian A. Vojnov
- Instituto de Ciencia y Tecnología Dr. César Milstein, Fundación Pablo Cassará, CONICETSaladillo 2468Ciudad de Buenos AiresC1440FFXArgentina
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Ference CM, Gochez AM, Behlau F, Wang N, Graham JH, Jones JB. Recent advances in the understanding of Xanthomonas citri ssp. citri pathogenesis and citrus canker disease management. MOLECULAR PLANT PATHOLOGY 2018; 19:1302-1318. [PMID: 29105297 PMCID: PMC6638175 DOI: 10.1111/mpp.12638] [Citation(s) in RCA: 70] [Impact Index Per Article: 11.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/20/2017] [Revised: 10/29/2017] [Accepted: 10/31/2017] [Indexed: 05/09/2023]
Abstract
Taxonomic status: Bacteria; Phylum Proteobacteria; Class Gammaproteobacteria; Order Xanthomonadales; Family Xanthomonadaceae; Genus Xanthomonas; Species Xanthomonas citri ssp. citri (Xcc). Host range: Compatible hosts vary in their susceptibility to citrus canker (CC), with grapefruit, lime and lemon being the most susceptible, sweet orange being moderately susceptible, and kumquat and calamondin being amongst the least susceptible. Microbiological properties: Xcc is a rod-shaped (1.5-2.0 × 0.5-0.75 µm), Gram-negative, aerobic bacterium with a single polar flagellum. The bacterium forms yellow colonies on culture media as a result of the production of xanthomonadin. Distribution: Present in South America, the British Virgin Islands, Africa, the Middle East, India, Asia and the South Pacific islands. Localized incidence in the USA, Argentina, Brazil, Bolivia, Uruguay, Senegal, Mali, Burkina Faso, Tanzania, Iran, Saudi Arabia, Yemen and Bangladesh. Widespread throughout Paraguay, Comoros, China, Japan, Malaysia and Vietnam. Eradicated from South Africa, Australia and New Zealand. Absent from Europe.
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Affiliation(s)
- Christopher M. Ference
- United States Department of Agriculture, Agricultural Research Service, US Horticultural Research LaboratoryFort PierceFL 34945USA
- Department of Plant PathologyUniversity of FloridaGainesvilleFL 32611USA
| | - Alberto M. Gochez
- Citrus Pathology, EEA INTA Bella VistaBella VistaCorrientes 3432Argentina
| | - Franklin Behlau
- Department of Research & DevelopmentFundo de Defesa da Citricultura (Fundecitrus)AraraquaraSão Paulo 14.807‐040Brazil
| | - Nian Wang
- Department of Microbiology and Cell Science, Citrus Research and Education Center, University of FloridaLake AlfredFL 33850USA
| | - James H. Graham
- Department of Soil and Water Science, Citrus Research and Education Center, University of FloridaLake AlfredFL 33850USA
| | - Jeffrey B. Jones
- Department of Plant PathologyUniversity of FloridaGainesvilleFL 32611USA
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Malamud F, Conforte VP, Rigano LA, Castagnaro AP, Marano MR, Morais do Amaral A, Vojnov AA. HrpM is involved in glucan biosynthesis, biofilm formation and pathogenicity in Xanthomonas citri ssp. citri. MOLECULAR PLANT PATHOLOGY 2012; 13:1010-8. [PMID: 22738424 PMCID: PMC6638875 DOI: 10.1111/j.1364-3703.2012.00809.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/11/2023]
Abstract
Xanthomonas citri ssp. citri (Xcc) is the causal agent of citrus canker. This bacterium develops a characteristic biofilm on both biotic and abiotic surfaces. A biofilm-deficient mutant was identified in a screening of a transposon mutagenesis library of the Xcc 306 strain constructed using the commercial Tn5 transposon EZ-Tn5 <KAN-2> Tnp Transposome (Epicentre). Sequence analysis of a mutant obtained in the screening revealed that a single copy of the EZ-Tn5 was inserted at position 446 of hrpM, a gene encoding a putative enzyme involved in glucan synthesis. We demonstrate for the first time that the product encoded by the hrpM gene is involved in β-1,2-glucan synthesis in Xcc. A mutation in hrpM resulted in no disease symptoms after 4 weeks of inoculation in lemon and grapefruit plants. The mutant also showed reduced ability to swim in soft agar and decreased resistance to H(2)O(2) in comparison with the wild-type strain. All defective phenotypes were restored to wild-type levels by complementation with the plasmid pBBR1-MCS containing an intact copy of the hrpM gene and its promoter. These results indicate that the hrpM gene contributes to Xcc growth and adaptation in its host plant.
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Affiliation(s)
- Florencia Malamud
- Instituto de Ciencia y Tecnología Dr Cesar Milstein, Fundación Pablo Cassará, CONICET, Saladillo 2468 C1440FFX, Ciudad de Buenos Aires, Argentina
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Jalan N, Aritua V, Kumar D, Yu F, Jones JB, Graham JH, Setubal JC, Wang N. Comparative genomic analysis of Xanthomonas axonopodis pv. citrumelo F1, which causes citrus bacterial spot disease, and related strains provides insights into virulence and host specificity. J Bacteriol 2011; 193:6342-57. [PMID: 21908674 PMCID: PMC3209208 DOI: 10.1128/jb.05777-11] [Citation(s) in RCA: 57] [Impact Index Per Article: 4.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/10/2011] [Accepted: 08/30/2011] [Indexed: 11/20/2022] Open
Abstract
Xanthomonas axonopodis pv. citrumelo is a citrus pathogen causing citrus bacterial spot disease that is geographically restricted within the state of Florida. Illumina, 454 sequencing, and optical mapping were used to obtain a complete genome sequence of X. axonopodis pv. citrumelo strain F1, 4.9 Mb in size. The strain lacks plasmids, in contrast to other citrus Xanthomonas pathogens. Phylogenetic analysis revealed that this pathogen is very close to the tomato bacterial spot pathogen X. campestris pv. vesicatoria 85-10, with a completely different host range. We also compared X. axonopodis pv. citrumelo to the genome of citrus canker pathogen X. axonopodis pv. citri 306. Comparative genomic analysis showed differences in several gene clusters, like those for type III effectors, the type IV secretion system, lipopolysaccharide synthesis, and others. In addition to pthA, effectors such as xopE3, xopAI, and hrpW were absent from X. axonopodis pv. citrumelo while present in X. axonopodis pv. citri. These effectors might be responsible for survival and the low virulence of this pathogen on citrus compared to that of X. axonopodis pv. citri. We also identified unique effectors in X. axonopodis pv. citrumelo that may be related to the different host range as compared to that of X. axonopodis pv. citri. X. axonopodis pv. citrumelo also lacks various genes, such as syrE1, syrE2, and RTX toxin family genes, which were present in X. axonopodis pv. citri. These may be associated with the distinct virulences of X. axonopodis pv. citrumelo and X. axonopodis pv. citri. Comparison of the complete genome sequence of X. axonopodis pv. citrumelo to those of X. axonopodis pv. citri and X. campestris pv. vesicatoria provides valuable insights into the mechanism of bacterial virulence and host specificity.
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Affiliation(s)
- Neha Jalan
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, 700 Experiment Station Road, Lake Alfred, Florida 33850
| | - Valente Aritua
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, 700 Experiment Station Road, Lake Alfred, Florida 33850
| | - Dibyendu Kumar
- Interdisciplinary Center for Biotechnology Research, 2033 Mowry Road, University of Florida, Gainesville, Florida 32611
| | - Fahong Yu
- Interdisciplinary Center for Biotechnology Research, 2033 Mowry Road, University of Florida, Gainesville, Florida 32611
| | - Jeffrey B. Jones
- Department of Plant Pathology, University of Florida, Gainesville, Florida 32611
| | - James H. Graham
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, 700 Experiment Station Road, Lake Alfred, Florida 33850
| | - João C. Setubal
- Virginia Bioinformatics Institute and Department of Computer Science, Virginia Polytechnic Institute and State University, Blacksburg, Virginia 24060-0477
| | - Nian Wang
- Citrus Research and Education Center, Department of Microbiology and Cell Science, University of Florida, 700 Experiment Station Road, Lake Alfred, Florida 33850
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Palmieri ACB, do Amaral AM, Homem RA, Machado MA. Differential expression of pathogenicity- and virulence-related genes of Xanthomonas axonopodis pv. citri under copper stress. Genet Mol Biol 2010; 33:348-53. [PMID: 21637493 PMCID: PMC3036875 DOI: 10.1590/s1415-47572010005000030] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2009] [Accepted: 10/14/2009] [Indexed: 11/21/2022] Open
Abstract
In this study, we used real-time quantitative PCR (RT-qPCR) to evaluate the expression of 32 genes of Xanthomonas axonopodis pv. citri related to pathogenicity and virulence that are also involved in copper detoxification. Nearly all of the genes were up-regulated, including copA and copB. Two genes homologous to members of the type II secretion system (xcsH and xcsC) and two involved in the degradation of plant cell wall components (pglA and pel) were the most expressed in response to an elevated copper concentration. The type II secretion system (xcs operon) and a few homologues of proteins putatively secreted by this system showed enhanced expression when the bacteria were exposed to a high concentration of copper sulfate. The enhanced expression of the genes of secretion II system during copper stress suggests that this pathway may have an important role in the adaptative response of X. axonopodis pv. citri to toxic compounds. These findings highlight the potential role of these genes in attenuating the toxicity of certain metals and could represent an important means of bacterial resistance against chemicals used to control diseases.
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9
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Giblot-Ducray D, Marefat A, Gillings MR, Parkinson NM, Bowman JP, Ophel-Keller K, Taylor C, Facelli E, Scott ES. Proposal of Xanthomonas translucens pv. pistaciae pv. nov., pathogenic to pistachio (Pistacia vera). Syst Appl Microbiol 2009; 32:549-57. [PMID: 19748753 DOI: 10.1016/j.syapm.2009.08.001] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2009] [Indexed: 11/15/2022]
Abstract
Strains of Xanthomonas translucens have caused dieback in the Australian pistachio industry for the last 15 years. Such pathogenicity to a dicotyledonous woody host contrasts with that of other pathovars of X. translucens, which are characterized by their pathogenicity to monocotyledonous plant families. Further investigations, using DNA-DNA hybridization, gyrB gene sequencing and integron screening, were conducted to confirm the taxonomic status of the X. translucens pathogenic to pistachio. DNA-DNA hybridization provided a clear classification, at the species level, of the pistachio pathogen as a X. translucens. In the gyrB-based phylogeny, strains of the pistachio pathogen clustered among the X. translucens pathovars as two distinct lineages. Integron screening revealed that the cassette arrays of strains of the pistachio pathogen were different from those of other Xanthomonas species, and again distinguished two groups. Together with previously reported pathogenicity data, these results confirm that the pistachio pathogen is a new pathovar of X. translucens and allow hypotheses about its origin. The proposed name is Xanthomonas translucens pv. pistaciae pv. nov.
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Affiliation(s)
- Danièle Giblot-Ducray
- The University of Adelaide, School of Agriculture, Food and Wine, Adelaide, South Australia 5005, Australia.
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10
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Ah-You N, Gagnevin L, Grimont PAD, Brisse S, Nesme X, Chiroleu F, Bui Thi Ngoc L, Jouen E, Lefeuvre P, Verniere C, Pruvost O. Polyphasic characterization of xanthomonads pathogenic to members of the Anacardiaceae and their relatedness to species of Xanthomonas. Int J Syst Evol Microbiol 2009; 59:306-18. [DOI: 10.1099/ijs.0.65453-0] [Citation(s) in RCA: 69] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
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Golmohammadi M, Cubero J, Peñalver J, Quesada JM, López MM, Llop P. Diagnosis of Xanthomonas axonopodis pv. citri, causal agent of citrus canker, in commercial fruits by isolation and PCR-based methods. J Appl Microbiol 2008; 103:2309-15. [PMID: 18045415 DOI: 10.1111/j.1365-2672.2007.03484.x] [Citation(s) in RCA: 42] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
AIMS To show the results of the detection of an EU quarantine organism, Xanthomonas axonopodis pv. citri (Xac), in citrus fruits imported from countries where this bacterium is present, using an integrated approach that includes isolation, pathogenicity assays and molecular techniques. METHODS AND RESULTS Citrus fruits with canker-like symptoms, exported to Spain from South American countries were analysed by several methods. Bacterial isolation, three conventional polymerase chain reaction (PCR) protocols, and real-time PCR with SYBR Green or a TaqMan probe, were compared. Canker-like lesions were disrupted in PBS buffer, and the extract used for bacterial isolation and DNA extraction followed by PCR amplification. Canker lesions, identified by PCR, showed viable bacteria in eleven of fifteen fruit samples. In 16 out of 130 lesions analysed from these samples, Xac was isolated, and pathogenicity on grapefruit leaves confirmed. By real-time PCR, using SYBR green or a Taqman probe, Xac was detected in 58 and 80 lesions respectively. By conventional PCR the bacterium was detected in 39-52 lesions depending on the protocol employed. CONCLUSIONS An integrated approach for reliable detection of Xac in lesions of fruit samples, employing several techniques and with real-time PCR using a TaqMan probe as the fastest and most sensitive screening method, has been established and validated and is proposed as a useful tool for the analysis of Xac on fresh fruits. SIGNIFICANCE AND IMPACT OF THE STUDY This work faces up to the real threat of the importation of citrus fruits that can harbour quarantine bacteria and will be useful in diagnostic laboratories for the analysis of commercial fresh fruits from countries where citrus canker is present.
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Affiliation(s)
- M Golmohammadi
- Instituto Valenciano de Investigaciones Agrarias, Carretera Moncada - Náquera, Valencia, Spain
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Rigano LA, Siciliano F, Enrique R, Sendín L, Filippone P, Torres PS, Qüesta J, Dow JM, Castagnaro AP, Vojnov AA, Marano MR. Biofilm formation, epiphytic fitness, and canker development in Xanthomonas axonopodis pv. citri. MOLECULAR PLANT-MICROBE INTERACTIONS : MPMI 2007; 20:1222-30. [PMID: 17918624 DOI: 10.1094/mpmi-20-10-1222] [Citation(s) in RCA: 141] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/12/2023]
Abstract
The phytopathogenic bacterium Xanthomonas axonopodis pv. citri is responsible for the canker disease affecting citrus plants throughout the world. Here, we have evaluated the role of bacterial attachment and biofilm formation in leaf colonization during canker development on lemon leaves. Crystal violet staining and confocal laser scanning microscopy analysis of X. axonopodis pv. citri strains expressing the green fluorescent protein were used to evaluate attachment and biofilm formation on abiotic and biotic (leaf) surfaces. Wild-type X. axonopodis pv. citri attached to and formed a complex, structured biofilm on glass in minimal medium containing glucose. Similar attachment and structured biofilm formation also were seen on lemon leaves. An X. axonopodis pv. citri gumB mutant strain, defective in production of the extracellular polysaccharide xanthan, did not form a structured biofilm on either abiotic or biotic surfaces. In addition, the X. axonopodis pv. citri gumB showed reduced growth and survival on leaf surfaces and reduced disease symptoms. These findings suggest an important role for formation of biofilms in the epiphytic survival of X. axonopodis pv. citri prior to development of canker disease.
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Affiliation(s)
- Luciano A Rigano
- Fundación Pablo Cassará, Centro de Ciencia y Tecnología Dr. Cesar Milstein, Saladillo 2468 C1440FFX, Ciudad de Buenos Aires, Argentina
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Arias CR, Olivares-Fuster O, Hayden K, Shoemaker CA, Grizzle JM, Klesius PH. First report of Yersinia ruckeri biotype 2 in the USA. JOURNAL OF AQUATIC ANIMAL HEALTH 2007; 19:35-40. [PMID: 18236630 DOI: 10.1577/h06-011.1] [Citation(s) in RCA: 31] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
A polyphasic characterization of atypical isolates of Yersinia ruckeri (causative agent of enteric redmouth disease in trout) obtained from hatchery-reared brown trout Salmo trutta in South Carolina was performed. The Y. ruckeri isolates were biochemically and genetically distinct from reference cultures, including the type strain, but were unequivocally ascribed to the species Y. ruckeri, based on API 20E, VITEK, fatty acid methyl ester profiles, and 16S rRNA gene sequencing analysis. These isolates were nonmotile and unable to hydrolyze Tween 20/80 and were therefore classified as Y. ruckeri biotype 2. Genetic fingerprint typing of the isolates via enterobacterial repetitive intergenic consensus (amplified by polymerase chain reaction) and fragment length polymorphism showed biotype 2 as a homogeneous group distinguishable from other Y. ruckeri isolates. This is the first report of Y. ruckeri biotype 2 in the USA.
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Affiliation(s)
- Cova R Arias
- Department of Fisheries and Allied Aquacultures, Auburn University, 203 Swingle Hall, Auburn, Alabama 36849, USA.
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Blanvillain S, Meyer D, Boulanger A, Lautier M, Guynet C, Denancé N, Vasse J, Lauber E, Arlat M. Plant carbohydrate scavenging through tonB-dependent receptors: a feature shared by phytopathogenic and aquatic bacteria. PLoS One 2007; 2:e224. [PMID: 17311090 PMCID: PMC1790865 DOI: 10.1371/journal.pone.0000224] [Citation(s) in RCA: 243] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2006] [Accepted: 01/26/2007] [Indexed: 01/12/2023] Open
Abstract
TonB-dependent receptors (TBDRs) are outer membrane proteins mainly known for the active transport of iron siderophore complexes in Gram-negative bacteria. Analysis of the genome of the phytopathogenic bacterium Xanthomonas campestris pv. campestris (Xcc), predicts 72 TBDRs. Such an overrepresentation is common in Xanthomonas species but is limited to only a small number of bacteria. Here, we show that one Xcc TBDR transports sucrose with a very high affinity, suggesting that it might be a sucrose scavenger. This TBDR acts with an inner membrane transporter, an amylosucrase and a regulator to utilize sucrose, thus defining a new type of carbohydrate utilization locus, named CUT locus, involving a TBDR for the transport of substrate across the outer membrane. This sucrose CUT locus is required for full pathogenicity on Arabidopsis, showing its importance for the adaptation to host plants. A systematic analysis of Xcc TBDR genes and a genome context survey suggested that several Xcc TBDRs belong to other CUT loci involved in the utilization of various plant carbohydrates. Interestingly, several Xcc TBDRs and CUT loci are conserved in aquatic bacteria such as Caulobacter crescentus, Colwellia psychrerythraea, Saccharophagus degradans, Shewanella spp., Sphingomonas spp. or Pseudoalteromonas spp., which share the ability to degrade a wide variety of complex carbohydrates and display TBDR overrepresentation. We therefore propose that TBDR overrepresentation and the presence of CUT loci designate the ability to scavenge carbohydrates. Thus CUT loci, which seem to participate to the adaptation of phytopathogenic bacteria to their host plants, might also play a very important role in the biogeochemical cycling of plant-derived nutrients in marine environments. Moreover, the TBDRs and CUT loci identified in this study are clearly different from those characterized in the human gut symbiont Bacteroides thetaiotaomicron, which allow glycan foraging, suggesting a convergent evolution of TBDRs in Proteobacteria and Bacteroidetes.
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Affiliation(s)
- Servane Blanvillain
- Laboratoire des Interactions Plantes-Microorganismes, Centre National de la Recherche Scientifique (CNRS)/Institut National de la Recherche Agronomique (INRA) UMR2594/441, Castanet-Tolosan, France
| | - Damien Meyer
- Laboratoire des Interactions Plantes-Microorganismes, Centre National de la Recherche Scientifique (CNRS)/Institut National de la Recherche Agronomique (INRA) UMR2594/441, Castanet-Tolosan, France
| | - Alice Boulanger
- Laboratoire des Interactions Plantes-Microorganismes, Centre National de la Recherche Scientifique (CNRS)/Institut National de la Recherche Agronomique (INRA) UMR2594/441, Castanet-Tolosan, France
| | - Martine Lautier
- Laboratoire des Interactions Plantes-Microorganismes, Centre National de la Recherche Scientifique (CNRS)/Institut National de la Recherche Agronomique (INRA) UMR2594/441, Castanet-Tolosan, France
- Université Paul Sabatier, Toulouse III, Toulouse, France
| | - Catherine Guynet
- Laboratoire des Interactions Plantes-Microorganismes, Centre National de la Recherche Scientifique (CNRS)/Institut National de la Recherche Agronomique (INRA) UMR2594/441, Castanet-Tolosan, France
| | - Nicolas Denancé
- Laboratoire des Interactions Plantes-Microorganismes, Centre National de la Recherche Scientifique (CNRS)/Institut National de la Recherche Agronomique (INRA) UMR2594/441, Castanet-Tolosan, France
| | - Jacques Vasse
- Laboratoire des Interactions Plantes-Microorganismes, Centre National de la Recherche Scientifique (CNRS)/Institut National de la Recherche Agronomique (INRA) UMR2594/441, Castanet-Tolosan, France
| | - Emmanuelle Lauber
- Laboratoire des Interactions Plantes-Microorganismes, Centre National de la Recherche Scientifique (CNRS)/Institut National de la Recherche Agronomique (INRA) UMR2594/441, Castanet-Tolosan, France
- * To whom correspondence should be addressed. E-mail: (EL); (MA)
| | - Matthieu Arlat
- Laboratoire des Interactions Plantes-Microorganismes, Centre National de la Recherche Scientifique (CNRS)/Institut National de la Recherche Agronomique (INRA) UMR2594/441, Castanet-Tolosan, France
- Université Paul Sabatier, Toulouse III, Toulouse, France
- * To whom correspondence should be addressed. E-mail: (EL); (MA)
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Cubero J, Graham JH. Quantitative real-time polymerase chain reaction for bacterial enumeration and allelic discrimination to differentiate xanthomonas strains on citrus. PHYTOPATHOLOGY 2005; 95:1333-1340. [PMID: 18943365 DOI: 10.1094/phyto-95-1333] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/26/2023]
Abstract
ABSTRACT Quantitative real-time polymerase chain reaction (QRT-PCR) was developed for identification and enumeration of bacteria in citrus plant samples infected with Xanthomonas axonopodis pvs. citri and citrumelo, the cause of citrus bacterial canker (CBC) and citrus bacterial spot (CBS), respectively. Three sets of primers based on the pathogenicity gene (pth) in X. axonopodis pv. citri, a ribosomal gene in X. axonopodis pv. citrumelo, and the leucine-responsive regulatory protein (lrp) in both pathovars were combined with TaqMan probes and applied for specific strain detection and quantification. Calibration curves for bacterial abundance in plant samples obtained with the three primer-probe combinations were congruent with colony counts on plates of semiselective medium in most of the cases. However, apparent overestimation of bacterial cells by QRT-PCR indicated the presence of nonculturable or nonviable cells in some samples. In addition to quantification, the lrp primers and probes permitted differentiation by allelic discrimination of Xanthomonas strains infecting citrus tissues. This technique is based on the utilization of two probes that detect a single nucleotide difference in the target sequence between different strains and was validated with a collection of cultured Xanthomonas strains as well as tissue with CBC and CBS lesions. Allelic discrimination is demonstrated to be a more specific and sensitive protocol than previously developed PCR-based methods for strain identification and quantification.
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Schaad NW, Postnikova E, Lacy GH, Sechler A, Agarkova I, Stromberg PE, Stromberg VK, Vidaver AK. Reclassification of Xanthomonas campestris pv. citri (ex Hasse 1915) Dye 1978 forms A, B/C/D, and E as X. smithii subsp. citri (ex Hasse) sp. nov. nom. rev. comb. nov., X. fuscans subsp. aurantifolii (ex Gabriel 1989) sp. nov. nom. rev. comb. nov., and X. alfalfae subsp. citrumelo (ex Riker and Jones) Gabriel et al., 1989 sp. nov. nom. rev. comb. nov.; X. campestris pv malvacearum (ex Smith 1901) Dye 1978 as X. smithii subsp. smithii nov. comb. nov. nom. nov.; X. campestris pv. alfalfae (ex Riker and Jones, 1935) Dye 1978 as X. alfalfae subsp. alfalfae (ex Riker et al., 1935) sp. nov. nom. rev.; and “var. fuscans” of X. campestris pv. phaseoli (ex Smith, 1987) Dye 1978 as X. fuscans subsp. fuscans sp. nov. Syst Appl Microbiol 2005; 28:494-518. [PMID: 16104350 DOI: 10.1016/j.syapm.2005.03.017] [Citation(s) in RCA: 110] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Bacterial canker of citrus is a serious disease of citrus worldwide. Five forms of the disease have been described, cankers "A", "B", "C", "D", and "E". Although considerable genetic diversity has been described among the causal agents of the five forms of citrus canker and supports multiple taxons, the causal agents currently are classified as pathovars citri ("A"), aurantifolii ("B/C/D") and citrumelo ("E") of a single species, Xanthomonas campestris pv. citri (or X. axonopodis pv. citri). To determine the taxonomic relatedness among strains of X. campestris pv. citri, we conducted DNA-DNA relatedness assays, sequenced the 16S-23S intergenic spacer (ITS) regions, and performed amplified fragment length polymorphism (AFLP) analysis, using 44 strains representative of the five recognized forms of citrus canker. Under stringent DNA reassociation conditions (Tm - 15 degrees C), three distinct genotypes of citrus pathogens were revealed: taxon I included all "A" strains; taxon II contained all "B", "C", and "D" strains; and taxon III contained all "E" strains. The three citrus taxa showed less than 50% (mean) DNA-DNA relatedness to each other and less than 30% (mean) to X. campestris pv. campestris and X. axonopodis pv. axonopodis. Taxa I and II strains share over 70% DNA relatedness to X. campestris pv. malvacearum and X. campestris pv. phaseoli var. fuscans, respectively (at Tm - 15 degrees C). Taxon III strains share 70% relatedness to X. campestris pv. alfalfae. Previous and present phenotypic data support these DNA reassociation data. Taxon II strains grow more slowly on agar media than taxa I and III strains. Taxa I and III strains utilize maltose, and liquefy gelatin whereas taxon II strains do not. Taxon I strains hydrolyze pectate (pH 7.0) whereas Taxon II strains do not. Taxon III strains utilize raffinose whereas Taxon I strains do not. Each taxon can be differentiated by serology and pathogenicity. We propose taxa I, II, and III citrus strains be named, respectively, Xanthomonas smithii subsp. citri (ex Hasse, 1915) sp. nov. nom. rev. comb. nov., Xanthomonas fuscans subsp. aurantifolii (ex Gabriel et al., 1989) sp. nov. nom. rev. comb. nov., and Xanthomonas alfalfae subsp. citrumelo (ex Riker and Jones) Gabriel et al., 1989 nov. rev. comb. nov. Furthermore, based on the analysis of 40 strains of 19 other xanthomonads, we propose to reclassify X. campestris pv. malvacearum (ex Smith, 1901) Dye 1978 as X. smithii subsp. smithii sp. nov. comb. nov. nom. nov.; X. campestris pv. alfalfae (ex Riker and Jones) Dye 1978 as X. alfalfae subsp. alfalfae (ex Riker et al., 1935) sp. nov. nov. rev.; and "var. fuscans" (ex Burkholder 1930) of X. campestris pv. phaseoli (ex Smith, 1897) as X. fuscans subsp. fuscans sp. nov.
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Affiliation(s)
- Norman W Schaad
- ARS-USDA, Foreign Disease-Weed Science Research Unit, 1301 Ditto Ave., Ft. Detrick, MD 21702, USA.
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Sun X, Stall RE, Jones JB, Cubero J, Gottwald TR, Graham JH, Dixon WN, Schubert TS, Chaloux PH, Stromberg VK, Lacy GH, Sutton BD. Detection and Characterization of a New Strain of Citrus Canker Bacteria from Key/Mexican Lime and Alemow in South Florida. PLANT DISEASE 2004; 88:1179-1188. [PMID: 30795311 DOI: 10.1094/pdis.2004.88.11.1179] [Citation(s) in RCA: 51] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/10/2023]
Abstract
In the Wellington and Lake Worth areas of Palm Beach County, FL, citrus canker appeared on Key/Mexican lime (Citrus aurantiifolia) and alemow (C. macrophylla) trees over a period of about 6 to 7 years before detection, but nearby canker-susceptible citrus, such as grapefruit (C. × paradisi) and sweet orange (C. sinensis), were unaffected. Colonies of the causal bacterium, isolated from leaf, stem, and fruit lesions, appeared similar to the Asiatic group of strains of Xanthomonas axonopodis pv. citri (Xac-A) on the nutrient agar plate, but the growth on lima bean agar slants was less mucoid. The bacterium produced erumpent, pustule-like lesions of typical Asiatic citrus canker syndrome after inoculation into Key/Mexican lime, but brownish, flat, and necrotic lesions on the leaves of Duncan grapefruit, Madame Vinous sweet orange, sour orange (C. aurantium), citron (C. medica), Orlando tangelo (C. reticulata × C. × paradisi), and trifoliate orange (Poncirus trifoliata). The bacterium did not react with the Xac-A specific monoclonal antibody A1 using enzyme-linked immunosorbent assay (ELISA) and could not be detected by polymerase chain reaction (PCR)-based assays using primers selected for Xac-A. DNA reassociation analysis confirmed that the pathogen, designated as Xac-AW, was more closely related to Xac-A and Xac-A* strains than X. axonopodis pv. aurantifolii or the citrus bacterial spot pathogen (X. axonopodis pv. citrumelo). The strain can be easily differentiated from Xac-A and Xac-A* using ELISA, PCR-based tests, fatty acid analysis, pulsed-field gel electrophoresis of genomic DNA, and host specificity.
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Affiliation(s)
- Xiaoan Sun
- Florida Department of Agriculture & Consumer Services, Division of Plant Industry, Gainesville 32614
| | - Robert E Stall
- Florida Department of Agriculture & Consumer Services, Division of Plant Industry, Gainesville 32614
| | - Jeffrey B Jones
- University of Florida, Department of Plant Pathology, Gainesville 32611
| | - Jaime Cubero
- University of Florida, IFAS, Citrus Research and Education Center, Lake Alfred 33850
| | - Tim R Gottwald
- USDA, Agricultural Research Service, U.S. Horticultural Research Laboratory, Ft. Pierce, FL 34945
| | - James H Graham
- University of Florida, IFAS, Citrus Research and Education Center, Lake Alfred 33850
| | - Wayne N Dixon
- Florida Department of Agriculture & Consumer Services, Division of Plant Industry, Gainesville 32614
| | - Tim S Schubert
- Florida Department of Agriculture & Consumer Services, Division of Plant Industry, Gainesville 32614
| | - Paul H Chaloux
- USDA Citrus Canker Eradication Program, Plantation, FL 33313
| | - Verlyn K Stromberg
- Virginia Polytechnic Institute and State University, Department of Plant Pathology, Physiology, and Weed Science, Blacksburg 24061
| | - George H Lacy
- Virginia Polytechnic Institute and State University, Department of Plant Pathology, Physiology, and Weed Science, Blacksburg 24061
| | - Bruce D Sutton
- Florida Department of Agriculture & Consumer Services, Division of Plant Industry, Gainesville 32614
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