1
|
Hamilton CD, Zaricor B, Dye CJ, Dresserl E, Michaels R, Allen C. Ralstonia solanacearum pandemic lineage strain UW551 overcomes inhibitory xylem chemistry to break tomato bacterial wilt resistance. MOLECULAR PLANT PATHOLOGY 2024; 25:e13395. [PMID: 37846613 PMCID: PMC10782650 DOI: 10.1111/mpp.13395] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/12/2023] [Revised: 08/01/2023] [Accepted: 09/15/2023] [Indexed: 10/18/2023]
Abstract
Plant-pathogenic Ralstonia strains cause bacterial wilt disease by colonizing xylem vessels of many crops, including tomato. Host resistance is the best control for bacterial wilt, but resistance mechanisms of the widely used Hawaii 7996 tomato breeding line (H7996) are unknown. Using growth in ex vivo xylem sap as a proxy for host xylem, we found that Ralstonia strain GMI1000 grows in sap from both healthy plants and Ralstonia-infected susceptible plants. However, sap from Ralstonia-infected H7996 plants inhibited Ralstonia growth, suggesting that in response to Ralstonia infection, resistant plants increase inhibitors in their xylem sap. Consistent with this, reciprocal grafting and defence gene expression experiments indicated that H7996 wilt resistance acts in both above- and belowground plant parts. Concerningly, H7996 resistance is broken by Ralstonia strain UW551 of the pandemic lineage that threatens highland tropical agriculture. Unlike other Ralstonia, UW551 grew well in sap from Ralstonia-infected H7996 plants. Moreover, other Ralstonia strains could grow in sap from H7996 plants previously infected by UW551. Thus, UW551 overcomes H7996 resistance in part by detoxifying inhibitors in xylem sap. Testing a panel of xylem sap compounds identified by metabolomics revealed that no single chemical differentially inhibits Ralstonia strains that cannot infect H7996. However, sap from Ralstonia-infected H7996 contained more phenolic compounds, which are known to be involved in plant antimicrobial defence. Culturing UW551 in this sap reduced total phenolic levels, indicating that the resistance-breaking Ralstonia strain degrades these chemical defences. Together, these results suggest that H7996 tomato wilt resistance depends in part on inducible phenolic compounds in xylem sap.
Collapse
Affiliation(s)
- Corri D. Hamilton
- Department of Plant PathologyUniversity of Wisconsin MadisonMadisonWisconsinUSA
- Department of Microbiology and ImmunologyUniversity of British ColumbiaVancouverBritish ColumbiaCanada
| | - Beatriz Zaricor
- Department of Plant PathologyUniversity of Wisconsin MadisonMadisonWisconsinUSA
| | - Carolyn Jean Dye
- Department of Plant PathologyUniversity of Wisconsin MadisonMadisonWisconsinUSA
| | - Emma Dresserl
- Department of Plant PathologyUniversity of Wisconsin MadisonMadisonWisconsinUSA
| | - Renee Michaels
- Department of Plant PathologyUniversity of Wisconsin MadisonMadisonWisconsinUSA
| | - Caitilyn Allen
- Department of Plant PathologyUniversity of Wisconsin MadisonMadisonWisconsinUSA
| |
Collapse
|
2
|
Qiu H, Wang B, Huang M, Sun X, Yu L, Cheng D, He W, Zhou D, Wu X, Song B, Tang N, Chen H. A novel effector RipBT contributes to Ralstonia solanacearum virulence on potato. MOLECULAR PLANT PATHOLOGY 2023; 24:947-960. [PMID: 37154802 PMCID: PMC10346376 DOI: 10.1111/mpp.13342] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/26/2022] [Revised: 03/21/2023] [Accepted: 04/05/2023] [Indexed: 05/10/2023]
Abstract
Ralstonia solanacearum is one of the most destructive plant-pathogenic bacteria, infecting more than 200 plant species, including potato (Solanum tuberosum) and many other solanaceous crops. R. solanacearum has numerous pathogenicity factors, and type III effectors secreted through type III secretion system (T3SS) are key factors to counteract host immunity. Here, we show that RipBT is a novel T3SS-secreted effector by using a cyaA reporter system. Transient expression of RipBT in Nicotiania benthamiana induced strong cell death in a plasma membrane-localization dependent manner. Notably, mutation of RipBT in R. solanacearum showed attenuated virulence on potato, while RipBT transgenic potato plants exhibited enhanced susceptibility to R. solanacearum. Interestingly, transcriptomic analyses suggest that RipBT may interfere with plant reactive oxygen species (ROS) metabolism during the R. solanacearum infection of potato roots. In addition, the expression of RipBT remarkably suppressed the flg22-induced pathogen-associated molecular pattern-triggered immunity responses, such as the ROS burst. Taken together, RipBT acts as a T3SS effector, promoting R. solanacearum infection on potato and presumably disturbing ROS homeostasis.
Collapse
Affiliation(s)
- Huishan Qiu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural CropsHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural AffairsHuazhong Agricultural UniversityWuhanChina
- Potato Engineering and Technology Research Center of Hubei ProvinceHuazhong Agricultural UniversityWuhanChina
- College of Horticulture and Forestry ScienceHuazhong Agricultural UniversityWuhanChina
| | - Bingsen Wang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural CropsHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural AffairsHuazhong Agricultural UniversityWuhanChina
- Potato Engineering and Technology Research Center of Hubei ProvinceHuazhong Agricultural UniversityWuhanChina
- College of Horticulture and Forestry ScienceHuazhong Agricultural UniversityWuhanChina
| | - Mengshu Huang
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural CropsHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural AffairsHuazhong Agricultural UniversityWuhanChina
- Potato Engineering and Technology Research Center of Hubei ProvinceHuazhong Agricultural UniversityWuhanChina
- College of Horticulture and Forestry ScienceHuazhong Agricultural UniversityWuhanChina
| | - Xiaohu Sun
- State Key Laboratory of Crop Stress Adaptation and ImprovementHenan UniversityKaifengChina
| | - Liu Yu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural CropsHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural AffairsHuazhong Agricultural UniversityWuhanChina
- Potato Engineering and Technology Research Center of Hubei ProvinceHuazhong Agricultural UniversityWuhanChina
- College of Horticulture and Forestry ScienceHuazhong Agricultural UniversityWuhanChina
| | - Dong Cheng
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural CropsHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural AffairsHuazhong Agricultural UniversityWuhanChina
- Potato Engineering and Technology Research Center of Hubei ProvinceHuazhong Agricultural UniversityWuhanChina
- College of Horticulture and Forestry ScienceHuazhong Agricultural UniversityWuhanChina
| | - Wenfeng He
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural CropsHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural AffairsHuazhong Agricultural UniversityWuhanChina
- Potato Engineering and Technology Research Center of Hubei ProvinceHuazhong Agricultural UniversityWuhanChina
- College of Horticulture and Forestry ScienceHuazhong Agricultural UniversityWuhanChina
| | - Dan Zhou
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural CropsHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural AffairsHuazhong Agricultural UniversityWuhanChina
- Potato Engineering and Technology Research Center of Hubei ProvinceHuazhong Agricultural UniversityWuhanChina
- College of Horticulture and Forestry ScienceHuazhong Agricultural UniversityWuhanChina
| | - Xintong Wu
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural CropsHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural AffairsHuazhong Agricultural UniversityWuhanChina
- Potato Engineering and Technology Research Center of Hubei ProvinceHuazhong Agricultural UniversityWuhanChina
- College of Horticulture and Forestry ScienceHuazhong Agricultural UniversityWuhanChina
| | - Botao Song
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural CropsHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural AffairsHuazhong Agricultural UniversityWuhanChina
- Potato Engineering and Technology Research Center of Hubei ProvinceHuazhong Agricultural UniversityWuhanChina
- College of Horticulture and Forestry ScienceHuazhong Agricultural UniversityWuhanChina
| | - Ning Tang
- State Key Laboratory of Crop Stress Adaptation and ImprovementHenan UniversityKaifengChina
| | - Huilan Chen
- National Key Laboratory for Germplasm Innovation & Utilization of Horticultural CropsHuazhong Agricultural UniversityWuhanChina
- Key Laboratory of Potato Biology and Biotechnology, Ministry of Agriculture and Rural AffairsHuazhong Agricultural UniversityWuhanChina
- Potato Engineering and Technology Research Center of Hubei ProvinceHuazhong Agricultural UniversityWuhanChina
- College of Horticulture and Forestry ScienceHuazhong Agricultural UniversityWuhanChina
| |
Collapse
|
3
|
Greenrod STE, Stoycheva M, Elphinstone J, Friman VP. Global diversity and distribution of prophages are lineage-specific within the Ralstonia solanacearum species complex. BMC Genomics 2022; 23:689. [PMID: 36199029 PMCID: PMC9535894 DOI: 10.1186/s12864-022-08909-7] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2022] [Accepted: 09/23/2022] [Indexed: 11/17/2022] Open
Abstract
Background Ralstonia solanacearum species complex (RSSC) strains are destructive plant pathogenic bacteria and the causative agents of bacterial wilt disease, infecting over 200 plant species worldwide. In addition to chromosomal genes, their virulence is mediated by mobile genetic elements including integrated DNA of bacteriophages, i.e., prophages, which may carry fitness-associated auxiliary genes or modulate host gene expression. Although experimental studies have characterised several prophages that shape RSSC virulence, the global diversity, distribution, and wider functional gene content of RSSC prophages are unknown. In this study, prophages were identified in a diverse collection of 192 RSSC draft genome assemblies originating from six continents. Results Prophages were identified bioinformatically and their diversity investigated using genetic distance measures, gene content, GC, and total length. Prophage distributions were characterised using metadata on RSSC strain geographic origin and lineage classification (phylotypes), and their functional gene content was assessed by identifying putative prophage-encoded auxiliary genes. In total, 313 intact prophages were identified, forming ten genetically distinct clusters. These included six prophage clusters with similarity to the Inoviridae, Myoviridae, and Siphoviridae phage families, and four uncharacterised clusters, possibly representing novel, previously undescribed phages. The prophages had broad geographical distributions, being present across multiple continents. However, they were generally host phylogenetic lineage-specific, and overall, prophage diversity was proportional to the genetic diversity of their hosts. The prophages contained many auxiliary genes involved in metabolism and virulence of both phage and bacteria. Conclusions Our results show that while RSSC prophages are highly diverse globally, they make lineage-specific contributions to the RSSC accessory genome, which could have resulted from shared coevolutionary history. Supplementary Information The online version contains supplementary material available at 10.1186/s12864-022-08909-7.
Collapse
Affiliation(s)
| | | | - John Elphinstone
- Fera Science Ltd, National Agri-Food Innovation Campus, Sand Hutton, York, UK
| | | |
Collapse
|
4
|
Clough SE, Jousset A, Elphinstone JG, Friman V. Combining in vitro and in vivo screening to identify efficient
Pseudomonas
biocontrol strains against the phytopathogenic bacterium
Ralstonia solanacearum. Microbiologyopen 2022; 11:e1283. [PMID: 35478286 PMCID: PMC9059233 DOI: 10.1002/mbo3.1283] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/02/2022] [Accepted: 03/31/2022] [Indexed: 11/09/2022] Open
Abstract
Although plant pathogens are traditionally controlled using synthetic agrochemicals, the availability of commercial bactericides is still limited. One potential control strategy could be the use of plant growth‐promoting bacteria (PGPB) to suppress pathogens via resource competition or the production of antimicrobial compounds. This study aimed to conduct in vitro and in vivo screening of eight Pseudomonas strains against Ralstonia solanacearum (the causative agent of bacterial wilt) and to investigate underlying mechanisms of potential pathogen suppression. We found that inhibitory effects were Pseudomonas strain‐specific, with strain CHA0 showing the highest pathogen suppression. Genomic screening identified 2,4‐diacetylphloroglucinol, pyoluteorin, and orfamides A and B secondary metabolite clusters in the genomes of the most inhibitory strains, which were investigated further. Although all these compounds suppressed R. solanacearum growth, only orfamide A was produced in the growth media based on mass spectrometry. Moreover, orfamide variants extracted from Pseudomonas cultures showed high pathogen suppression. Using the “Micro‐Tom” tomato cultivar, it was found that CHA0 could reduce bacterial wilt disease incidence with one of the two tested pathogen strains. Together, these findings suggest that a better understanding of Pseudomonas–Ralstonia interactions in the rhizosphere is required to successfully translate in vitro findings into agricultural applications.
Collapse
Affiliation(s)
- Sophie E. Clough
- Department of Biology University of York York UK
- Department of Biosciences Chemistry Durham University Durham UK
| | - Alexandre Jousset
- Department of Biology, Institute of Environmental Biology, Ecology and Biodiversity Group Utrecht University Utrecht The Netherlands
| | | | | |
Collapse
|
5
|
Salinier J, Lefebvre V, Besombes D, Burck H, Causse M, Daunay MC, Dogimont C, Goussopoulos J, Gros C, Maisonneuve B, McLeod L, Tobal F, Stevens R. The INRAE Centre for Vegetable Germplasm: Geographically and Phenotypically Diverse Collections and Their Use in Genetics and Plant Breeding. PLANTS (BASEL, SWITZERLAND) 2022; 11:plants11030347. [PMID: 35161327 PMCID: PMC8838894 DOI: 10.3390/plants11030347] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/06/2021] [Revised: 01/20/2022] [Accepted: 01/21/2022] [Indexed: 05/14/2023]
Abstract
The French National Research Institute for Agriculture, Food and the Environment (INRAE) conserves and distributes five vegetable collections as seeds: the aubergine* (in this article the word aubergine refers to eggplant), pepper, tomato, melon and lettuce collections, together with their wild or cultivated relatives, are conserved in Avignon, France. Accessions from the collections have geographically diverse origins, are generally well-described and fixed for traits of agronomic or scientific interest and have available passport data. In addition to currently conserving over 10,000 accessions (between 900 and 3000 accessions per crop), the centre maintains scientific collections such as core collections and bi- or multi-parental populations, which have also been genotyped with SNP markers. Each collection has its own merits and highlights, which are discussed in this review: the aubergine collection is a rich source of crop wild relatives of Solanum; the pepper, melon and lettuce collections have been screened for resistance to plant pathogens, including viruses, fungi, oomycetes and insects; and the tomato collection has been at the heart of genome-wide association studies for fruit quality traits and environmental stress tolerance.
Collapse
|
6
|
Chepsergon J, Motaung TE, Moleleki LN. "Core" RxLR effectors in phytopathogenic oomycetes: A promising way to breeding for durable resistance in plants? Virulence 2021; 12:1921-1935. [PMID: 34304703 PMCID: PMC8516161 DOI: 10.1080/21505594.2021.1948277] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2021] [Revised: 06/11/2021] [Accepted: 06/18/2021] [Indexed: 12/30/2022] Open
Abstract
Phytopathogenic oomycetes are known to successfully infect their hosts due to their ability to secrete effector proteins. Of interest to many researchers are effectors with the N-terminal RxLR motif (Arginine-any amino acid-Leucine-Arginine). Owing to advances in genome sequencing, we can now comprehend the high level of diversity among oomycete effectors, and similarly, their conservation within and among species referred to here as "core" RxLR effectors (CREs). Currently, there is a considerable number of CREs that have been identified in oomycetes. Functional characterization of these CREs propose their virulence role with the potential of targeting central cellular processes that are conserved across diverse plant species. We reason that effectors that are highly conserved and recognized by the host, could be harnessed in engineering plants for durable as well as broad-spectrum resistance.
Collapse
Affiliation(s)
- Jane Chepsergon
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Thabiso E. Motaung
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, Gauteng, South Africa
| | - Lucy Novungayo Moleleki
- Department of Biochemistry, Genetics and Microbiology, Forestry and Agricultural Biotechnology Institute, University of Pretoria, Pretoria, Gauteng, South Africa
| |
Collapse
|
7
|
Elsayed TR, Grosch R, Smalla K. Potato plant spheres and to a lesser extent the soil type influence the proportion and diversity of bacterial isolates with in vitro antagonistic activity towards Ralstonia solanacearum. FEMS Microbiol Ecol 2021; 97:6155061. [PMID: 33674848 DOI: 10.1093/femsec/fiab038] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2020] [Accepted: 02/25/2021] [Indexed: 12/14/2022] Open
Abstract
Ralstonia solanacearum biovar2-race3 (Rs r3b2) is an epidemic soil-borne bacterial phytopathogen causing brown rot disease in potato. In this study, we assessed how three soil types stored at the same field site influenced the proportion and diversity of bacterial isolates with in vitro antagonistic activity towards Rs in bulk soil and different potato plant spheres (rhizosphere, endorhiza and endocaulosphere; ecto- and endosphere of seed and yield tubers). In general, the plate counts observed for each sample type were not significantly different. A total of 96 colonies per sample type was picked and screened for in vitro antagonistic activity against Rs. Antagonists were obtained from all bulk soils and plant spheres with the highest proportion obtained from the endorhiza and endocaulosphere of potato plants. BOX-PCR fingerprints of antagonists showed that some were specific for particular plant spheres independent of the soil type, while others originated from different plant spheres of a particular soil type. The majority of antagonists belonged to Pseudomonas. A high proportion of antagonists produced siderophores, and interestingly antagonists from potato tubers frequently carried multiple antibiotic production genes. Our data showed an enrichment of bacteria with genes or traits potentially involved in biocontrol in the rhizosphere and in endophytic compartments. We report that the proportion and diversity of in vitro antagonists towards Rs isolated from bulk soil and different spheres of potato plants grown under field conditions in three different soil types was mainly shaped by the plant sphere and to a lesser extent by the soil type. Bacteria with antagonistic activity towards Ralstonia solanacearum were isolated from all plant spheres and bulk soils but their proportion was highest in endophytic compartments.
Collapse
Affiliation(s)
- Tarek R Elsayed
- Julius Kühn-Institute (JKI), Federal Research Centre for Cultivated Plants, Institute for Epidemiology and Pathogen Diagnostics, Messeweg 11-12, 38104 Braunschweig, Germany.,Department of Microbiology, Faculty of Agriculture, Cairo University, Giza, Egypt
| | - Rita Grosch
- Leibniz Institute of Vegetable and Ornamental Crops (IGZ) e.V., Plant-Microbe Systems, Großbeeren, Germany
| | - Kornelia Smalla
- Julius Kühn-Institute (JKI), Federal Research Centre for Cultivated Plants, Institute for Epidemiology and Pathogen Diagnostics, Messeweg 11-12, 38104 Braunschweig, Germany
| |
Collapse
|
8
|
Moon H, Pandey A, Yoon H, Choi S, Jeon H, Prokchorchik M, Jung G, Witek K, Valls M, McCann HC, Kim M, Jones JDG, Segonzac C, Sohn KH. Identification of RipAZ1 as an avirulence determinant of Ralstonia solanacearum in Solanum americanum. MOLECULAR PLANT PATHOLOGY 2021; 22:317-333. [PMID: 33389783 PMCID: PMC7865085 DOI: 10.1111/mpp.13030] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2020] [Revised: 11/07/2020] [Accepted: 11/23/2020] [Indexed: 05/08/2023]
Abstract
Ralstonia solanacearum causes bacterial wilt disease in many plant species. Type III-secreted effectors (T3Es) play crucial roles in bacterial pathogenesis. However, some T3Es are recognized by corresponding disease resistance proteins and activate plant immunity. In this study, we identified the R. solanacearum T3E protein RipAZ1 (Ralstonia injected protein AZ1) as an avirulence determinant in the black nightshade species Solanum americanum. Based on the S. americanum accession-specific avirulence phenotype of R. solanacearum strain Pe_26, 12 candidate avirulence T3Es were selected for further analysis. Among these candidates, only RipAZ1 induced a cell death response when transiently expressed in a bacterial wilt-resistant S. americanum accession. Furthermore, loss of ripAZ1 in the avirulent R. solanacearum strain Pe_26 resulted in acquired virulence. Our analysis of the natural sequence and functional variation of RipAZ1 demonstrated that the naturally occurring C-terminal truncation results in loss of RipAZ1-triggered cell death. We also show that the 213 amino acid central region of RipAZ1 is sufficient to induce cell death in S. americanum. Finally, we show that RipAZ1 may activate defence in host cell cytoplasm. Taken together, our data indicate that the nucleocytoplasmic T3E RipAZ1 confers R. solanacearum avirulence in S. americanum. Few avirulence genes are known in vascular bacterial phytopathogens and ripAZ1 is the first one in R. solanacearum that is recognized in black nightshades. This work thus opens the way for the identification of disease resistance genes responsible for the specific recognition of RipAZ1, which can be a source of resistance against the devastating bacterial wilt disease.
Collapse
Affiliation(s)
- Hayoung Moon
- Department of Life SciencesPohang University of Science and TechnologyPohangRepublic of Korea
| | - Ankita Pandey
- Department of Life SciencesPohang University of Science and TechnologyPohangRepublic of Korea
| | - Hayeon Yoon
- Department of Life SciencesPohang University of Science and TechnologyPohangRepublic of Korea
| | - Sera Choi
- Department of Life SciencesPohang University of Science and TechnologyPohangRepublic of Korea
| | - Hyelim Jeon
- Department of Agriculture, Forestry and BioresourcesSeoul National UniversitySeoulRepublic of Korea
- Plant Immunity Research CenterSeoul National UniversitySeoulRepublic of Korea
| | - Maxim Prokchorchik
- Department of Life SciencesPohang University of Science and TechnologyPohangRepublic of Korea
| | - Gayoung Jung
- Department of Life SciencesPohang University of Science and TechnologyPohangRepublic of Korea
| | - Kamil Witek
- The Sainsbury LaboratoryUniversity of East AngliaNorwichUK
| | - Marc Valls
- Department of GeneticsUniversity of BarcelonaBarcelonaSpain
- Centre for Research in Agricultural Genomics (CSIC‐IRTA‐UAB‐UB)BellaterraSpain
| | - Honour C. McCann
- New Zealand Institute of Advanced StudiesMassey UniversityAucklandNew Zealand
- Max Planck Institute for Developmental BiologyTübingenGermany
| | - Min‐Sung Kim
- Department of Life SciencesPohang University of Science and TechnologyPohangRepublic of Korea
- Division of Integrative Biosciences and BiotechnologyPohang University of Science and TechnologyRepublic of Korea
| | | | - Cécile Segonzac
- Department of Agriculture, Forestry and BioresourcesSeoul National UniversitySeoulRepublic of Korea
- Plant Immunity Research CenterSeoul National UniversitySeoulRepublic of Korea
- Department of Plant Science, Plant Genomics and Breeding InstituteAgricultural Life Science Research InstituteSeoul National UniversitySeoulRepublic of Korea
| | - Kee Hoon Sohn
- Department of Life SciencesPohang University of Science and TechnologyPohangRepublic of Korea
- School of Interdisciplinary Bioscience and BioengineeringPohang University of Science and TechnologyPohangRepublic of Korea
| |
Collapse
|
9
|
Prokchorchik M, Pandey A, Moon H, Kim W, Jeon H, Jung G, Jayaraman J, Poole S, Segonzac C, Sohn KH, McCann HC. Host adaptation and microbial competition drive Ralstonia solanacearum phylotype I evolution in the Republic of Korea. Microb Genom 2020; 6:mgen000461. [PMID: 33151139 PMCID: PMC7725338 DOI: 10.1099/mgen.0.000461] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2020] [Accepted: 10/06/2020] [Indexed: 12/13/2022] Open
Abstract
Bacterial wilt caused by the Ralstonia solanacearum species complex (RSSC) threatens the cultivation of important crops worldwide. We sequenced 30 RSSC phylotype I (R. pseudosolanacearum) strains isolated from pepper (Capsicum annuum) and tomato (Solanum lycopersicum) across the Republic of Korea. These isolates span the diversity of phylotype I, have extensive effector repertoires and are subject to frequent recombination. Recombination hotspots among South Korean phylotype I isolates include multiple predicted contact-dependent inhibition loci, suggesting that microbial competition plays a significant role in Ralstonia evolution. Rapid diversification of secreted effectors presents challenges for the development of disease-resistant plant varieties. We identified potential targets for disease resistance breeding by testing for allele-specific host recognition of T3Es present among South Korean phyloype I isolates. The integration of pathogen population genomics and molecular plant pathology contributes to the development of location-specific disease control and development of plant cultivars with durable resistance to relevant threats.
Collapse
Affiliation(s)
- Maxim Prokchorchik
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | - Ankita Pandey
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | - Hayoung Moon
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | - Wanhui Kim
- Department of Plant Science, Plant Genome and Breeding Institute, Agricultural Life Science Research Institute, Seoul National University, Seoul 08826, Republic of Korea
- Plant Immunity Research Center, Seoul National University, Seoul 08826, Republic of Korea
| | - Hyelim Jeon
- Plant Immunity Research Center, Seoul National University, Seoul 08826, Republic of Korea
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul 08826, Republic of Korea
| | - Gayoung Jung
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | - Jay Jayaraman
- The New Zealand Institute for Plant and Food Research, Auckland, New Zealand
| | - Stephen Poole
- Department of Molecular, Cellular and Developmental Biology, University of California Santa Barbara, Santa Barbara, USA
| | - Cécile Segonzac
- Department of Plant Science, Plant Genome and Breeding Institute, Agricultural Life Science Research Institute, Seoul National University, Seoul 08826, Republic of Korea
- Plant Immunity Research Center, Seoul National University, Seoul 08826, Republic of Korea
- Department of Agriculture, Forestry and Bioresources, Seoul National University, Seoul 08826, Republic of Korea
| | - Kee Hoon Sohn
- Department of Life Sciences, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
- School of Interdisciplinary Bioscience and Bioengineering, Pohang University of Science and Technology, Pohang 37673, Republic of Korea
| | - Honour C. McCann
- New Zealand Institute for Advanced Study, Massey University Albany, New Zealand
- Max Planck Institute for Developmental Biology, Tübingen, Germany
| |
Collapse
|
10
|
Sedighian N, Taghavi SM, Hamzehzarghani H, van der Wolf JM, Wicker E, Osdaghi E. Potato-Infecting Ralstonia solanacearum Strains in Iran Expand Knowledge on the Global Diversity of Brown Rot Ecotype of the Pathogen. PHYTOPATHOLOGY 2020; 110:1647-1656. [PMID: 32401153 DOI: 10.1094/phyto-03-20-0072-r] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Bacterial wilt and brown rot disease caused by Ralstonia solanacearum species complex (RSSC) is one of the major constraints of potato (Solanum tuberosum) production around the globe. During 2017 to 2018, an extensive field survey was conducted in six potato-growing provinces of Iran to monitor the status of bacterial wilt disease. Pathogenicity and host range assays using 59 bacterial strains isolated in Iran showed that they were pathogenic on eggplant, red nightshade, pepper, potato and tomato, while nonpathogenic on common bean, cowpea, cucumber, sunflower, zinnia and zucchini. PCR-based diagnosis revealed that the strains belong to the phylotype IIB/sequevar 1 (IIB/I) lineage of the RSSC. Furthermore, a five-gene multilocus sequence analysis and typing (egl, fliC, gyrB, mutS, and rplB) confirmed the phylogenetically near-homogeneous nature of the strains within IIB/I lineage. Four sequence types were identified among 58 IIB/1 strains isolated in Iran. Phylogenetically near-homogeneous nature of the strains in Iran raise questions about the mode of inoculum entry of the bacterial wilt pathogen into the country (one-time introduction versus multiple introductions), while the geographic origin of the Iranian R. solanacearum strains remains undetermined. Furthermore, sequence typing showed that there were shared alleles (haplotypes) and sequence types among the strains isolated in geographically distant areas in Iran, suggesting intranational transmission of the pathogen in the country.
Collapse
Affiliation(s)
- Nasim Sedighian
- Department of Plant Protection, College of Agriculture, Shiraz University, Shiraz 71441-65186, Iran
| | - S Mohsen Taghavi
- Department of Plant Protection, College of Agriculture, Shiraz University, Shiraz 71441-65186, Iran
| | | | - Jan M van der Wolf
- Wageningen University and Research, Business Unit Biointeractions and Plant Health, 6700 AA, Wageningen, The Netherlands
| | - Emmanuel Wicker
- IPME, Univ Montpellier, CIRAD, IRD, Montpellier, France
- CIRAD, UMR IPME, Montpellier, France
| | - Ebrahim Osdaghi
- Department of Plant Protection, College of Agriculture, Shiraz University, Shiraz 71441-65186, Iran
| |
Collapse
|
11
|
Sang Y, Yu W, Zhuang H, Wei Y, Derevnina L, Yu G, Luo J, Macho AP. Intra-strain Elicitation and Suppression of Plant Immunity by Ralstonia solanacearum Type-III Effectors in Nicotiana benthamiana. PLANT COMMUNICATIONS 2020; 1:100025. [PMID: 33367244 PMCID: PMC7747989 DOI: 10.1016/j.xplc.2020.100025] [Citation(s) in RCA: 37] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/24/2019] [Revised: 12/12/2019] [Accepted: 01/16/2020] [Indexed: 05/11/2023]
Abstract
Effector proteins delivered inside plant cells are powerful weapons for bacterial pathogens, but this exposes the pathogen to potential recognition by the plant immune system. Therefore, the effector repertoire of a given pathogen must be balanced for a successful infection. Ralstonia solanacearum is an aggressive pathogen with a large repertoire of secreted effectors. One of these effectors, RipE1, is conserved in most R. solanacearum strains sequenced to date. In this work, we found that RipE1 triggers immunity in N. benthamiana, which requires the immune regulator SGT1, but not EDS1 or NRCs. Interestingly, RipE1-triggered immunity induces the accumulation of salicylic acid (SA) and the overexpression of several genes encoding phenylalanine-ammonia lyases (PALs), suggesting that the unconventional PAL-mediated pathway is responsible for the observed SA biosynthesis. Surprisingly, RipE1 recognition also induces the expression of jasmonic acid (JA)-responsive genes and JA biosynthesis, suggesting that both SA and JA may act cooperatively in response to RipE1. We further found that RipE1 expression leads to the accumulation of glutathione in plant cells, which precedes the activation of immune responses. R. solanacearum secretes another effector, RipAY, which is known to inhibit immune responses by degrading cellular glutathione. Accordingly, RipAY inhibits RipE1-triggered immune responses. This work shows a strategy employed by R. solanacearum to counteract the perception of its effector proteins by plant immune system.
Collapse
Affiliation(s)
- Yuying Sang
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 201602, China
| | - Wenjia Yu
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 201602, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Haiyan Zhuang
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 201602, China
| | - Yali Wei
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 201602, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Lida Derevnina
- The Sainsbury Laboratory, University of East Anglia, Norwich Research Park, Norwich NR4 7UH, UK
| | - Gang Yu
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 201602, China
| | - Jiamin Luo
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 201602, China
- University of Chinese Academy of Sciences, Beijing, China
| | - Alberto P. Macho
- Shanghai Center for Plant Stress Biology, CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of Sciences, Shanghai 201602, China
| |
Collapse
|
12
|
Santiago TR, Lopes CA, Caetano-Anollés G, Mizubuti ESG. Genetic Structure of Ralstonia solanacearum and Ralstonia pseudosolanacearum in Brazil. PLANT DISEASE 2020; 104:1019-1025. [PMID: 31994983 DOI: 10.1094/pdis-09-19-1929-re] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/10/2023]
Abstract
Bacterial wilt-causing Ralstonia threaten numerous crops throughout the world. We studied the population structure of 196 isolates of Ralstonia solanacearum and 39 isolates of Ralstonia pseudosolanacearum, which were collected from potato- and tomato-growing areas in 19 states of Brazil. Regardless of the species, three groups of isolates were identified. One group encompassed R. pseudosolanacearum isolates. The other two groups comprise isolates of R. solanacearum (phylotype II) split according to geographic regions, one made of isolates from the North and Northeast and the other made of isolates from the Central, Southeast, and South regions (CSS). Among the isolates collected in CSS, those from tomato were genetically distinct from the potato isolates. The genetic variability in the population of R. pseudosolanacearum was lower than that of R. solanacearum, suggesting that the former was introduced in Brazil. Conversely, the high genetic variability of R. solanacearum in all regions, hosts, and times supports the hypothesis that this species is autochthonous in South America, more precisely in Brazil and Peru. For R. solanacearum, higher variability and lower migration rates were observed when tomato isolates were analyzed, indicating that the variability is caused mainly by the differences of the local, native soil population. The North subpopulation was distinct from all others, possibly because of differences in environmental features of this region. The proximity of some geographic regions and the movement of potato tubers could have facilitated migration and therefore low genetic differentiation between geographic regions. Finally, geography, which also influences host distribution, affects the structure of the population of R. solanacearum in Brazil. Despite quarantine procedures in Brazil, increasing levels of trade are a threat to biosecurity, and these results emphasize the need for improving our regional efforts to prevent the dispersal of pathogens.
Collapse
Affiliation(s)
- Thaís Ribeiro Santiago
- Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36.570-900, Brazil
| | | | | | - Eduardo S G Mizubuti
- Departamento de Fitopatologia, Universidade Federal de Viçosa, Viçosa, Minas Gerais, 36.570-900, Brazil
| |
Collapse
|
13
|
Improved method for genotyping the causative agent of crayfish plague (Aphanomyces astaci) based on mitochondrial DNA. Parasitology 2019; 146:1022-1029. [PMID: 30975238 DOI: 10.1017/s0031182019000283] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
Aphanomyces astaci causes crayfish plague, which is a devastating disease of European freshwater crayfish. The likely first introduction of A. astaci into Europe was in the mid-19th century in Italy, presumably with the introduction of North American crayfish. These crayfish can carry A. astaci in their cuticle as a benign infection. Aphanomyces astaci rapidly spread across Europe causing the decline of the highly susceptible indigenous crayfish species. Random amplified polymorphic DNA-PCR analysis of A. astaci pure cultures characterized five genotype groups (A, B, C, D and E). Current A. astaci genotyping techniques (microsatellites and genotype-specific regions, both targeting nuclear DNA) can be applied directly to DNA extracted from infected cuticles but require high infection levels. Therefore, they are not suitable for genotyping benign infections in North American crayfish (carriers). In the present study, we combine bioinformatics and molecular biology techniques to develop A. astaci genotyping molecular markers that target the mitochondrial DNA, increasing the sensitivity of the genotyping tools. The assays were validated on DNA extracts of A. astaci pure cultures, crayfish tissue extractions from crayfish plague outbreaks and tissue extractions from North American carriers. We demonstrate the presence of A. astaci genotype groups A and B in UK waters.
Collapse
|
14
|
Lorang J. Necrotrophic Exploitation and Subversion of Plant Defense: A Lifestyle or Just a Phase, and Implications in Breeding Resistance. PHYTOPATHOLOGY 2019; 109:332-346. [PMID: 30451636 DOI: 10.1094/phyto-09-18-0334-ia] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Breeding disease-resistant plants is a critical, environmentally friendly component of any strategy to sustainably feed and clothe the 9.8 billion people expected to live on Earth by 2050. Here, I review current literature detailing plant defense responses as they relate to diverse biological outcomes; disease resistance, susceptibility, and establishment of mutualistic plant-microbial relationships. Of particular interest is the degree to which these outcomes are a function of plant-associated microorganisms' lifestyles; biotrophic, hemibiotrophic, necrotrophic, or mutualistic. For the sake of brevity, necrotrophic pathogens and the necrotrophic phase of pathogenicity are emphasized in this review, with special attention given to the host-specific pathogens that exploit defense. Defense responses related to generalist necrotrophs and mutualists are discussed in the context of excellent reviews by others. In addition, host evolutionary trade-offs of disease resistance with other desirable traits are considered in the context of breeding for durable disease resistance.
Collapse
Affiliation(s)
- Jennifer Lorang
- Department of Botany, 2082 Cordley Hall, Oregon State University, Corvallis 97331
| |
Collapse
|
15
|
Addy HS, Ahmad AA, Huang Q. Molecular and Biological Characterization of Ralstonia Phage RsoM1USA, a New Species of P2virus, Isolated in the United States. Front Microbiol 2019; 10:267. [PMID: 30837978 PMCID: PMC6389784 DOI: 10.3389/fmicb.2019.00267] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/05/2018] [Accepted: 02/01/2019] [Indexed: 12/11/2022] Open
Abstract
The first Ralstonia-infecting bacteriophage from soil of the United States, designated RsoM1USA, was isolated from a tomato field in Florida. Electron microscopy revealed that phage RsoM1USA is member of the genus P2virus in the family Myoviridae with an icosahedral head of about 66 nm in diameter, a contractile tail of about 152 nm in length, and a long “neck.” Phage RsoM1USA infected 12 of the 30 tested R. solanacearum species complex strains collected worldwide in each of the three Ralstonia species: R. solanacearum, R. pseudosolanacearum, and R. syzygii. The phage completed its infection cycle 180 min post infection with a burst size of about 56 particles per cell. Phage RsoM1USA has a genome of 39,309 nucleotides containing 58 open reading frames (ORFs) and is closely related to Ralstonia phage RSA1 of the species Ralstonia virus RSA1. The genomic organization of phage RsoM1USA is also similar to that of phage RSA1, but their integrases share no sequence homology. In addition, we determined that the integration of phage RsoM1USA into its susceptible R. solanacearum strain K60 is mediated by the 3′ 45-base portion of the threonine tRNA (TGT), not arginine tRNA (CCG) as reported for phage RSA1, confirming that the two phages use different mechanism for integration. Our proteomic analysis of the purified virions supported the annotation of the main structural proteins. Infection of a susceptible R. solanacearum strain RUN302 by phage RsoM1USA resulted in significantly reduced growth of the infected bacterium in vitro, but not virulence in tomato plants, as compared to its uninfected RUN302 strain. Due to its differences from phage RSA1, phage RsoM1USA should be considered the type member of a new species with a proposed species name of Ralstonia virus RsoM1USA.
Collapse
Affiliation(s)
- Hardian Susilo Addy
- Floral and Nursery Plants Research Unit, United States National Arboretum, United States Department of Agriculture-Agricultural Research Service, Beltsville, MD, United States.,Department of Plant Protection, Faculty of Agriculture, University of Jember, Jember, Indonesia
| | - Abdelmonim Ali Ahmad
- Floral and Nursery Plants Research Unit, United States National Arboretum, United States Department of Agriculture-Agricultural Research Service, Beltsville, MD, United States.,Department of Plant Pathology, Faculty of Agriculture, Minia University, El-minia, Egypt
| | - Qi Huang
- Floral and Nursery Plants Research Unit, United States National Arboretum, United States Department of Agriculture-Agricultural Research Service, Beltsville, MD, United States
| |
Collapse
|
16
|
da Silva Xavier A, de Almeida JCF, de Melo AG, Rousseau GM, Tremblay DM, de Rezende RR, Moineau S, Alfenas‐Zerbini P. Characterization of CRISPR-Cas systems in the Ralstonia solanacearum species complex. MOLECULAR PLANT PATHOLOGY 2019; 20:223-239. [PMID: 30251378 PMCID: PMC6637880 DOI: 10.1111/mpp.12750] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/08/2023]
Abstract
Clustered regularly interspaced short palindromic repeats (CRISPRs) are composed of an array of short DNA repeat sequences separated by unique spacer sequences that are flanked by associated (Cas) genes. CRISPR-Cas systems are found in the genomes of several microbes and can act as an adaptive immune mechanism against invading foreign nucleic acids, such as phage genomes. Here, we studied the CRISPR-Cas systems in plant-pathogenic bacteria of the Ralstonia solanacearum species complex (RSSC). A CRISPR-Cas system was found in 31% of RSSC genomes present in public databases. Specifically, CRISPR-Cas types I-E and II-C were found, with I-E being the most common. The presence of the same CRISPR-Cas types in distinct Ralstonia phylotypes and species suggests the acquisition of the system by a common ancestor before Ralstonia species segregation. In addition, a Cas1 phylogeny (I-E type) showed a perfect geographical segregation of phylotypes, supporting an ancient acquisition. Ralstoniasolanacearum strains CFBP2957 and K60T were challenged with a virulent phage, and the CRISPR arrays of bacteriophage-insensitive mutants (BIMs) were analysed. No new spacer acquisition was detected in the analysed BIMs. The functionality of the CRISPR-Cas interference step was also tested in R. solanacearum CFBP2957 using a spacer-protospacer adjacent motif (PAM) delivery system, and no resistance was observed against phage phiAP1. Our results show that the CRISPR-Cas system in R. solanacearum CFBP2957 is not its primary antiviral strategy.
Collapse
Affiliation(s)
- André da Silva Xavier
- Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária (BIOAGRO)Universidade Federal de ViçosaViçosaMG36570‐000Brazil
| | - Juliana Cristina Fraleon de Almeida
- Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária (BIOAGRO)Universidade Federal de ViçosaViçosaMG36570‐000Brazil
| | - Alessandra Gonçalves de Melo
- Département de Biochimie, de Microbiologie, et de Bioinformatique, Faculté des Sciences et de GénieUniversité LavalQuébec CityQCGIV0A6Canada
| | - Geneviève M. Rousseau
- Département de Biochimie, de Microbiologie, et de Bioinformatique, Faculté des Sciences et de GénieUniversité LavalQuébec CityQCGIV0A6Canada
- Félix d'Hérelle Reference Center for Bacterial Viruses, and GREB, Faculté de Médecine DentaireUniversité LavalQuébec CityQCGIV0A6Canada
| | - Denise M. Tremblay
- Département de Biochimie, de Microbiologie, et de Bioinformatique, Faculté des Sciences et de GénieUniversité LavalQuébec CityQCGIV0A6Canada
- Félix d'Hérelle Reference Center for Bacterial Viruses, and GREB, Faculté de Médecine DentaireUniversité LavalQuébec CityQCGIV0A6Canada
| | - Rafael Reis de Rezende
- Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária (BIOAGRO)Universidade Federal de ViçosaViçosaMG36570‐000Brazil
| | - Sylvain Moineau
- Département de Biochimie, de Microbiologie, et de Bioinformatique, Faculté des Sciences et de GénieUniversité LavalQuébec CityQCGIV0A6Canada
- Félix d'Hérelle Reference Center for Bacterial Viruses, and GREB, Faculté de Médecine DentaireUniversité LavalQuébec CityQCGIV0A6Canada
| | - Poliane Alfenas‐Zerbini
- Departamento de Microbiologia, Instituto de Biotecnologia Aplicada à Agropecuária (BIOAGRO)Universidade Federal de ViçosaViçosaMG36570‐000Brazil
| |
Collapse
|
17
|
Morel A, Guinard J, Lonjon F, Sujeeun L, Barberis P, Genin S, Vailleau F, Daunay M, Dintinger J, Poussier S, Peeters N, Wicker E. The eggplant AG91-25 recognizes the Type III-secreted effector RipAX2 to trigger resistance to bacterial wilt (Ralstonia solanacearum species complex). MOLECULAR PLANT PATHOLOGY 2018; 19:2459-2472. [PMID: 30073750 PMCID: PMC6638172 DOI: 10.1111/mpp.12724] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/22/2017] [Revised: 06/26/2018] [Accepted: 06/27/2018] [Indexed: 05/04/2023]
Abstract
To deploy durable plant resistance, we must understand its underlying molecular mechanisms. Type III effectors (T3Es) and their recognition play a central role in the interaction between bacterial pathogens and crops. We demonstrate that the Ralstonia solanacearum species complex (RSSC) T3E ripAX2 triggers specific resistance in eggplant AG91-25, which carries the major resistance locus EBWR9. The eggplant accession AG91-25 is resistant to the wild-type R. pseudosolanacearum strain GMI1000, whereas a ripAX2 defective mutant of this strain can cause wilt. Notably, the addition of ripAX2 from GMI1000 to PSS4 suppresses wilt development, demonstrating that RipAX2 is an elicitor of AG91-25 resistance. RipAX2 has been shown previously to induce effector-triggered immunity (ETI) in the wild relative eggplant Solanum torvum, and its putative zinc (Zn)-binding motif (HELIH) is critical for ETI. We show that, in our model, the HELIH motif is not necessary for ETI on AG91-25 eggplant. The ripAX2 gene was present in 68.1% of 91 screened RSSC strains, but in only 31.1% of a 74-genome collection comprising R. solanacearum and R. syzygii strains. Overall, it is preferentially associated with R. pseudosolanacearum phylotype I. RipAX2GMI1000 appears to be the dominant allele, prevalent in both R. pseudosolanacearum and R. solanacearum, suggesting that the deployment of AG91-25 resistance could control efficiently bacterial wilt in the Asian, African and American tropics. This study advances the understanding of the interaction between RipAX2 and the resistance genes at the EBWR9 locus, and paves the way for both functional genetics and evolutionary analyses.
Collapse
Affiliation(s)
- Arry Morel
- LIPMUniversité de Toulouse, INRA, CNRS,F‐31326Castanet‐TolosanFrance
| | - Jérémy Guinard
- Université de La RéunionUMR PVBMTF‐97410Saint‐Pierre, La RéunionFrance
- CIRADUMR PVBMTF‐97410Saint‐Pierre, La RéunionFrance
| | - Fabien Lonjon
- LIPMUniversité de Toulouse, INRA, CNRS,F‐31326Castanet‐TolosanFrance
| | | | - Patrick Barberis
- LIPMUniversité de Toulouse, INRA, CNRS,F‐31326Castanet‐TolosanFrance
| | - Stéphane Genin
- LIPMUniversité de Toulouse, INRA, CNRS,F‐31326Castanet‐TolosanFrance
| | - Fabienne Vailleau
- LIPMUniversité de Toulouse, INRA, CNRS,F‐31326Castanet‐TolosanFrance
| | | | | | - Stéphane Poussier
- LIPMUniversité de Toulouse, INRA, CNRS,F‐31326Castanet‐TolosanFrance
| | - Nemo Peeters
- LIPMUniversité de Toulouse, INRA, CNRS,F‐31326Castanet‐TolosanFrance
| | - Emmanuel Wicker
- CIRADUMR PVBMTF‐97410Saint‐Pierre, La RéunionFrance
- IPME, Université de Montpellier, CIRADIRDF‐34394MontpellierFrance
| |
Collapse
|
18
|
Ravelomanantsoa S, Vernière C, Rieux A, Costet L, Chiroleu F, Arribat S, Cellier G, Pruvost O, Poussier S, Robène I, Guérin F, Prior P. Molecular Epidemiology of Bacterial Wilt in the Madagascar Highlands Caused by Andean (Phylotype IIB-1) and African (Phylotype III) Brown Rot Strains of the Ralstonia solanacearum Species Complex. FRONTIERS IN PLANT SCIENCE 2018; 8:2258. [PMID: 29379515 PMCID: PMC5775269 DOI: 10.3389/fpls.2017.02258] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/16/2017] [Accepted: 12/27/2017] [Indexed: 05/21/2023]
Abstract
The Ralstonia solanacearum species complex (RSSC) is a highly diverse cluster of bacterial strains found worldwide, many of which are destructive and cause bacterial wilt (BW) in a wide range of host plants. In 2009, potato production in Madagascar was dramatically affected by several BW epidemics. Controlling this disease is critical for Malagasy potato producers. The first important step toward control is the characterization of strains and their putative origins. The genetic diversity and population structure of the RSSC were investigated in the major potato production areas of the Highlands. A large collection of strains (n = 1224) was assigned to RSSC phylotypes based on multiplex polymerase chain reaction (PCR). Phylotypes I and III have been present in Madagascar for a long time but rarely associated with major potato BW outbreaks. The marked increase of BW prevalence was found associated with phylotype IIB sequevar 1 (IIB-1) strains (n = 879). This is the first report of phylotype IIB-1 strains in Madagascar. In addition to reference strains, epidemic IIB-1 strains (n = 255) were genotyped using the existing MultiLocus Variable-Number Tandem Repeat Analysis (MLVA) scheme RS2-MLVA9, producing 31 haplotypes separated into two related clonal complexes (CCs). One major CC included most of the worldwide haplotypes distributed across wide areas. A regional-scale investigation suggested that phylotype IIB-1 strains were introduced and massively spread via latently infected potato seed tubers. Additionally, the genetic structure of phylotype IIB-1 likely resulted from a bottleneck/founder effect. The population structure of phylotype III, described here for the first time in Madagascar, exhibited a different pattern. Phylotype III strains (n = 217) were genotyped using the highly discriminatory MLVA scheme RS3-MLVA16. High genetic diversity was uncovered, with 117 haplotypes grouped into 11 CCs. Malagasy phylotype III strains were highly differentiated from continental African strains, suggesting no recent migration from the continent. Overall, population structure of phylotype III involves individual small CCs that correlate to restricted geographic areas in Madagascar. The evidence suggests, if at all, that African phylotype III strains are not efficiently transmitted through latently infected potato seed tubers.
Collapse
Affiliation(s)
- Santatra Ravelomanantsoa
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Saint-Pierre, France
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, University of Réunion, Saint-Denis, France
- Faculty of Sciences, University of Antananarivo, Antananarivo, Madagascar
| | - Christian Vernière
- Unité Mixte de Recherche, Biologie et Génétique des Interactions Plante-Parasite, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Montpellier, France
| | - Adrien Rieux
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Saint-Pierre, France
| | - Laurent Costet
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Saint-Pierre, France
| | - Frédéric Chiroleu
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Saint-Pierre, France
| | - Sandrine Arribat
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Saint-Pierre, France
| | - Gilles Cellier
- Tropical Pests and Diseases Unit, Plant Health Laboratory, Agence Nationale de Sécurité Sanitaire de l’Alimentation, de l’Environnement et du Travail, Saint-Pierre, France
| | - Olivier Pruvost
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Saint-Pierre, France
| | - Stéphane Poussier
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, University of Réunion, Saint-Denis, France
| | - Isabelle Robène
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, Centre de Coopération Internationale en Recherche Agronomique pour le Développement, Saint-Pierre, France
| | - Fabien Guérin
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, University of Réunion, Saint-Denis, France
| | - Philippe Prior
- Unité Mixte de Recherche, Peuplements Végétaux et Bioagresseurs en Milieu Tropical, Institut National de la Recherche Agronomique, Saint-Pierre, France
| |
Collapse
|
19
|
Sang Y, Wang Y, Ni H, Cazalé A, She Y, Peeters N, Macho AP. The Ralstonia solanacearum type III effector RipAY targets plant redox regulators to suppress immune responses. MOLECULAR PLANT PATHOLOGY 2018; 19:129-142. [PMID: 27768829 PMCID: PMC6638004 DOI: 10.1111/mpp.12504] [Citation(s) in RCA: 45] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/23/2016] [Revised: 09/28/2016] [Accepted: 10/17/2016] [Indexed: 05/07/2023]
Abstract
The subversion of plant cellular functions is essential for bacterial pathogens to proliferate in host plants and cause disease. Most bacterial plant pathogens employ a type III secretion system to inject type III effector (T3E) proteins inside plant cells, where they contribute to the pathogen-induced alteration of plant physiology. In this work, we found that the Ralstonia solanacearum T3E RipAY suppresses plant immune responses triggered by bacterial elicitors and by the phytohormone salicylic acid. Further biochemical analysis indicated that RipAY associates in planta with thioredoxins from Nicotiana benthamiana and Arabidopsis. Interestingly, RipAY displays γ-glutamyl cyclotransferase (GGCT) activity to degrade glutathione in plant cells, which is required for the reported suppression of immune responses. Given the importance of thioredoxins and glutathione as major redox regulators in eukaryotic cells, RipAY activity may constitute a novel and powerful virulence strategy employed by R. solanacearum to suppress immune responses and potentially alter general redox signalling in host cells.
Collapse
Affiliation(s)
- Yuying Sang
- Shanghai Center for Plant Stress Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of SciencesShanghai 201602China
- CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of SciencesShanghai 200031China
| | - Yaru Wang
- Shanghai Center for Plant Stress Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of SciencesShanghai 201602China
- CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of SciencesShanghai 200031China
| | - Hong Ni
- Shanghai Center for Plant Stress Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of SciencesShanghai 201602China
| | | | - Yi‐Min She
- Shanghai Center for Plant Stress Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of SciencesShanghai 201602China
| | - Nemo Peeters
- LIPM, Université de Toulouse, INRA, CNRSCastanet‐Tolosan 31326France
| | - Alberto P. Macho
- Shanghai Center for Plant Stress Biology, Shanghai Institutes of Biological Sciences, Chinese Academy of SciencesShanghai 201602China
- CAS Center for Excellence in Molecular Plant Sciences, Shanghai Institutes of Biological Sciences, Chinese Academy of SciencesShanghai 200031China
| |
Collapse
|
20
|
Pilet-Nayel ML, Moury B, Caffier V, Montarry J, Kerlan MC, Fournet S, Durel CE, Delourme R. Quantitative Resistance to Plant Pathogens in Pyramiding Strategies for Durable Crop Protection. FRONTIERS IN PLANT SCIENCE 2017; 8:1838. [PMID: 29163575 PMCID: PMC5664368 DOI: 10.3389/fpls.2017.01838] [Citation(s) in RCA: 96] [Impact Index Per Article: 13.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 10/10/2017] [Indexed: 05/18/2023]
Abstract
Quantitative resistance has gained interest in plant breeding for pathogen control in low-input cropping systems. Although quantitative resistance frequently has only a partial effect and is difficult to select, it is considered more durable than major resistance (R) genes. With the exponential development of molecular markers over the past 20 years, resistance QTL have been more accurately detected and better integrated into breeding strategies for resistant varieties with increased potential for durability. This review summarizes current knowledge on the genetic inheritance, molecular basis, and durability of quantitative resistance. Based on this knowledge, we discuss how strategies that combine major R genes and QTL in crops can maintain the effectiveness of plant resistance to pathogens. Combining resistance QTL with complementary modes of action appears to be an interesting strategy for breeding effective and potentially durable resistance. Combining quantitative resistance with major R genes has proven to be a valuable approach for extending the effectiveness of major genes. In the plant genomics era, improved tools and methods are becoming available to better integrate quantitative resistance into breeding strategies. Nevertheless, optimal combinations of resistance loci will still have to be identified to preserve resistance effectiveness over time for durable crop protection.
Collapse
Affiliation(s)
- Marie-Laure Pilet-Nayel
- Institute for Genetics, Environment and Plant Protection (INRA), UMR 1349, Leu Rheu, France
- PISOM, UMT INRA-Terres Inovia, Le Rheu, France
| | | | - Valérie Caffier
- Research Institute of Horticulture and Seeds (INRA), UMR 1345, Beaucouzé, France
| | - Josselin Montarry
- Institute for Genetics, Environment and Plant Protection (INRA), UMR 1349, Leu Rheu, France
| | - Marie-Claire Kerlan
- Institute for Genetics, Environment and Plant Protection (INRA), UMR 1349, Leu Rheu, France
| | - Sylvain Fournet
- Institute for Genetics, Environment and Plant Protection (INRA), UMR 1349, Leu Rheu, France
| | - Charles-Eric Durel
- Research Institute of Horticulture and Seeds (INRA), UMR 1345, Beaucouzé, France
| | - Régine Delourme
- Institute for Genetics, Environment and Plant Protection (INRA), UMR 1349, Leu Rheu, France
| |
Collapse
|
21
|
Hayes MM, MacIntyre AM, Allen C. Complete Genome Sequences of the Plant Pathogens Ralstonia solanacearum Type Strain K60 and R. solanacearum Race 3 Biovar 2 Strain UW551. GENOME ANNOUNCEMENTS 2017; 5:e01088-17. [PMID: 28983002 PMCID: PMC5629059 DOI: 10.1128/genomea.01088-17] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Subscribe] [Scholar Register] [Received: 08/31/2017] [Accepted: 09/01/2017] [Indexed: 11/20/2022]
Abstract
Ralstonia solanacearum is a globally distributed plant pathogen that causes bacterial wilt diseases of many crop hosts, threatening both sustenance farming and industrial agriculture. Here, we present closed genome sequences for the R. solanacearum type strain, K60, and the cool-tolerant potato brown rot strain R. solanacearum UW551, a highly regulated U.S. select agent pathogen.
Collapse
Affiliation(s)
- Madeline M Hayes
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - April M MacIntyre
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Caitilyn Allen
- Department of Plant Pathology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| |
Collapse
|
22
|
Ahmad AA, Stulberg MJ, Mershon JP, Mollov DS, Huang Q. Molecular and biological characterization of ϕRs551, a filamentous bacteriophage isolated from a race 3 biovar 2 strain of Ralstonia solanacearum. PLoS One 2017; 12:e0185034. [PMID: 28934297 PMCID: PMC5608472 DOI: 10.1371/journal.pone.0185034] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2017] [Accepted: 09/04/2017] [Indexed: 01/05/2023] Open
Abstract
A filamentous bacteriophage, designated ϕRs551, was isolated and purified from the quarantine and select agent phytopathogen Ralstonia solanacearum race 3 biovar 2 strain UW551 (phylotype IIB sequevar 1) grown under normal culture conditions. Electron microscopy suggested that ϕRs551 is a member of the family Inoviridae, and is about 1200 nm long and 7 nm wide. ϕRs551 has a genome of 7929 nucleotides containing 14 open reading frames, and is the first isolated virion that contains a resolvase (ORF13) and putative type-2 phage repressor (ORF14). Unlike other R. solanacearum phages isolated from soil, the genome sequence of ϕRs551 is not only 100% identical to its prophage sequence in the deposited genome of R. solanacearum strain UW551 from which the phage was isolated, but is also surprisingly found with 100% identity in the deposited genomes of 10 other phylotype II sequevar 1 strains of R. solanacearum. Furthermore, it is homologous to genome RS-09-161, resulting in the identification of a new prophage, designated RSM10, in a R. solanacearum strain from India. When ORF13 and a core attP site of ϕRs551 were either deleted individually or in combination, phage integration was not observed, suggesting that similar to other filamentous R. solanacearum ϕRSM phages, ϕRs551 relies on its resolvase and the core att sequence for site-directed integration into its susceptible R. solanacearum strain. The integration occurred four hours after phage infection. Infection of a susceptible R. solanacearum strain RUN302 by ϕRs551 resulted in less fluidal colonies and EPS production, and reduced motilities of the bacterium. Interestingly, infection of RUN302 by ϕRs551 also resulted in reduced virulence, rather than enhanced or loss of virulence caused by other ϕRSM phages. Study of bacteriophages of R. solanacearum would contribute to a better understanding of the phage-bacterium-environment interactions in order to develop integrated management strategies to combat R. solanacearum.
Collapse
Affiliation(s)
- Abdelmonim Ali Ahmad
- Floral and Nursery Plants Research Unit, United States National Arboretum, U.S. Dept. of Agriculture-Agricultural Research Service, Beltsville, Maryland, United States of America
- Department of Plant Pathology, Faculty of Agriculture, Minia University, El-minia, Egypt
| | - Michael J. Stulberg
- Floral and Nursery Plants Research Unit, United States National Arboretum, U.S. Dept. of Agriculture-Agricultural Research Service, Beltsville, Maryland, United States of America
| | - John Patrick Mershon
- Floral and Nursery Plants Research Unit, United States National Arboretum, U.S. Dept. of Agriculture-Agricultural Research Service, Beltsville, Maryland, United States of America
| | - Dimitre S. Mollov
- National Germplasm Resources Laboratory, U.S. Dept. of Agriculture-Agricultural Research Service, Beltsville, Maryland, United States of America
| | - Qi Huang
- Floral and Nursery Plants Research Unit, United States National Arboretum, U.S. Dept. of Agriculture-Agricultural Research Service, Beltsville, Maryland, United States of America
| |
Collapse
|
23
|
Bocsanczy AM, Huguet-Tapia JC, Norman DJ. Comparative Genomics of Ralstonia solanacearum Identifies Candidate Genes Associated with Cool Virulence. FRONTIERS IN PLANT SCIENCE 2017; 8:1565. [PMID: 28955357 PMCID: PMC5601409 DOI: 10.3389/fpls.2017.01565] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/29/2017] [Accepted: 08/28/2017] [Indexed: 06/01/2023]
Abstract
Strains of the Ralstonia solanacearum species complex in the phylotype IIB group are capable of causing Bacterial Wilt disease in potato and tomato at temperatures lower than 24°C. The capability of these strains to survive and to incite infection at temperatures colder than their normally tropical boundaries represents a threat to United States agriculture in temperate regions. In this work, we used a comparative genomics approach to identify orthologous genes linked to the lower temperature virulence phenotype. Six R. solanacearum cool virulent (CV) strains were compared to six strains non-pathogenic at low temperature (NPLT). CV strains can cause Bacterial Wilt symptoms at temperatures below 24°C, while NPLT cannot. Four R. solanacearum strains were sequenced for this work in order to complete the comparison. An orthologous genes comparison identified 44 genes present only in CV strains and 19 genes present only in NPLT strains. Gene annotation revealed a high percentage of genes compared with whole genomes in the transcriptional regulator and transport categories. A single nucleotide polymorphism (SNP) analysis identified 265 genes containing conserved non-synonymous SNPs in CV strains. Ten genes in the pathogenicity category were identified in this group. Comparisons of type 3 secretion system, type 6 secretion system (T6SS) clusters, and associated effectors did not indicate a correlation with the CV phenotype except for one T6SS VGR effector potentially associated with the CV phenotype. This is the first R. solanacearum genomic comparative analysis of multiple strains with different temperature related virulence. The candidate genes identified by this comparison are potential factors involved in virulence at low temperatures that need to be investigated. The high percentage of transcriptional regulators among the genes present only in CV strains supports the hypothesis that temperature dependent regulation of virulence genes explains the differential virulence phenotype at low temperatures. This comparison contributes to find new possible connections of temperature dependent virulence to the previously described complex regulatory system involving quorum-sensing, phenotype conversion (phcA), acyl-HSL production and responses to SA. It also added novel candidate T6SS effectors and useful detailed information about the T6SS in R. solanacearum.
Collapse
Affiliation(s)
- Ana M. Bocsanczy
- Mid-Florida Research and Education Center, Department of Plant Pathology, University of Florida, ApopkaFL, United States
| | - Jose C. Huguet-Tapia
- Department of Plant Pathology, University of Florida, GainesvilleFL, United States
| | - David J. Norman
- Mid-Florida Research and Education Center, Department of Plant Pathology, University of Florida, ApopkaFL, United States
| |
Collapse
|
24
|
McCann HC, Li L, Liu Y, Li D, Pan H, Zhong C, Rikkerink EH, Templeton MD, Straub C, Colombi E, Rainey PB, Huang H. Origin and Evolution of the Kiwifruit Canker Pandemic. Genome Biol Evol 2017; 9:932-944. [PMID: 28369338 PMCID: PMC5388287 DOI: 10.1093/gbe/evx055] [Citation(s) in RCA: 64] [Impact Index Per Article: 9.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/13/2017] [Indexed: 12/18/2022] Open
Abstract
Recurring epidemics of kiwifruit (Actinidia spp.) bleeding canker disease are caused by Pseudomonas syringae pv. actinidiae (Psa). In order to strengthen understanding of population structure, phylogeography, and evolutionary dynamics, we isolated Pseudomonas from cultivated and wild kiwifruit across six provinces in China. Based on the analysis of 80 sequenced Psa genomes, we show that China is the origin of the pandemic lineage but that strain diversity in China is confined to just a single clade. In contrast, Korea and Japan harbor strains from multiple clades. Distinct independent transmission events marked introduction of the pandemic lineage into New Zealand, Chile, Europe, Korea, and Japan. Despite high similarity within the core genome and minimal impact of within-clade recombination, we observed extensive variation even within the single clade from which the global pandemic arose.
Collapse
Affiliation(s)
- Honour C. McCann
- New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand
| | - Li Li
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Yifei Liu
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| | - Dawei Li
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Hui Pan
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Caihong Zhong
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
| | - Erik H.A. Rikkerink
- The New Zealand Institute for Plant and Food Research Limited, Auckland, New Zealand
| | - Matthew D. Templeton
- The New Zealand Institute for Plant and Food Research Limited, Auckland, New Zealand
- School of Biological Sciences, University of Auckland, New Zealand
| | - Christina Straub
- New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand
| | - Elena Colombi
- New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand
| | - Paul B. Rainey
- New Zealand Institute for Advanced Study, Massey University, Auckland, New Zealand
- Department of Microbial Population Biology, Max Planck Institute for Evolutionary Biology, Plön, Germany
- École Supérieure de Physique et de Chimie Industrielles de la Ville de Paris (ESPCI ParisTech), CNRS UMR 8231 PSL Research University, Paris, France
| | - Hongwen Huang
- Key Laboratory of Plant Germplasm Enhancement and Specialty Agriculture, Wuhan Botanical Garden, Chinese Academy of Sciences, Wuhan, China
- Key Laboratory of Plant Resources Conservation and Sustainable Utilization, South China Botanical Garden, Chinese Academy of Sciences, Guangzhou, China
| |
Collapse
|
25
|
Baltrus DA, McCann HC, Guttman DS. Evolution, genomics and epidemiology of Pseudomonas syringae: Challenges in Bacterial Molecular Plant Pathology. MOLECULAR PLANT PATHOLOGY 2017; 18:152-168. [PMID: 27798954 PMCID: PMC6638251 DOI: 10.1111/mpp.12506] [Citation(s) in RCA: 43] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/24/2016] [Revised: 10/25/2016] [Accepted: 10/26/2016] [Indexed: 05/12/2023]
Abstract
A remarkable shift in our understanding of plant-pathogenic bacteria is underway. Until recently, nearly all research on phytopathogenic bacteria was focused on a small number of model strains, which provided a deep, but narrow, perspective on plant-microbe interactions. Advances in genome sequencing technologies have changed this by enabling the incorporation of much greater diversity into comparative and functional research. We are now moving beyond a typological understanding of a select collection of strains to a more generalized appreciation of the breadth and scope of plant-microbe interactions. The study of natural populations and evolution has particularly benefited from the expansion of genomic data. We are beginning to have a much deeper understanding of the natural genetic diversity, niche breadth, ecological constraints and defining characteristics of phytopathogenic species. Given this expanding genomic and ecological knowledge, we believe the time is ripe to evaluate what we know about the evolutionary dynamics of plant pathogens.
Collapse
Affiliation(s)
| | - Honour C. McCann
- New Zealand Institute for Advanced StudyMassey UniversityAuckland 0632New Zealand
| | - David S. Guttman
- Department of Cell and Systems BiologyUniversity of TorontoTorontoON M5S 3B2Canada
- Centre for the Analysis of Genome Evolution and FunctionUniversity of TorontoTorontoON M5S 3B2Canada
| |
Collapse
|
26
|
Monteil CL, Yahara K, Studholme DJ, Mageiros L, Méric G, Swingle B, Morris CE, Vinatzer BA, Sheppard SK. Population-genomic insights into emergence, crop adaptation and dissemination of Pseudomonas syringae pathogens. Microb Genom 2016; 2:e000089. [PMID: 28348830 PMCID: PMC5359406 DOI: 10.1099/mgen.0.000089] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2016] [Accepted: 09/13/2016] [Indexed: 12/24/2022] Open
Abstract
Many bacterial pathogens are well characterized but, in some cases, little is known about the populations from which they emerged. This limits understanding of the molecular mechanisms underlying disease. The crop pathogen Pseudomonas syringae sensu lato has been widely isolated from the environment, including wild plants and components of the water cycle, and causes disease in several economically important crops. Here, we compared genome sequences of 45 P. syringae crop pathogen outbreak strains with 69 closely related environmental isolates. Phylogenetic reconstruction revealed that crop pathogens emerged many times independently from environmental populations. Unexpectedly, differences in gene content between environmental populations and outbreak strains were minimal with most virulence genes present in both. However, a genome-wide association study identified a small number of genes, including the type III effector genes hopQ1 and hopD1, to be associated with crop pathogens, but not with environmental populations, suggesting that this small group of genes may play an important role in crop disease emergence. Intriguingly, genome-wide analysis of homologous recombination revealed that the locus Psyr 0346, predicted to encode a protein that confers antibiotic resistance, has been frequently exchanged among lineages and thus may contribute to pathogen fitness. Finally, we found that isolates from diseased crops and from components of the water cycle, collected during the same crop disease epidemic, form a single population. This provides the strongest evidence yet that precipitation and irrigation water are an overlooked inoculum source for disease epidemics caused by P. syringae.
Collapse
Affiliation(s)
- Caroline L Monteil
- 4Laboratoire de Bioénergétique Cellulaire, Institut de Biosciences et Biotechnologies d'Aix-Marseille, CEA, 13108, Saint-Paul-lès-Durance, France.,3INRA, UR0407 Pathologie Végétale, Montfavet cedex, France.,1Institute of Life Science, College of Medicine, Swansea University, Swansea, UK.,2Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA, USA
| | - Koji Yahara
- 1Institute of Life Science, College of Medicine, Swansea University, Swansea, UK.,5National Institute of Infectious Diseases, Tokyo, Japan
| | | | - Leonardos Mageiros
- 1Institute of Life Science, College of Medicine, Swansea University, Swansea, UK
| | - Guillaume Méric
- 7The Milner Centre for Evolution, Department of Biology and Biotechnology, University of Bath, Claverton Down, Bath, UK
| | - Bryan Swingle
- 8School of Integrative Plant Science, Section of Plant Pathology and Plant-Microbe Biology, Cornell University, Ithaca, NY, USA
| | - Cindy E Morris
- 3INRA, UR0407 Pathologie Végétale, Montfavet cedex, France
| | - Boris A Vinatzer
- 2Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg, VA, USA
| | - Samuel K Sheppard
- 7The Milner Centre for Evolution, Department of Biology and Biotechnology, University of Bath, Claverton Down, Bath, UK.,9Department of Zoology, University of Oxford, Oxford, UK
| |
Collapse
|
27
|
Sakthivel K, Gautam RK, Kumar K, Dam Roy S, Kumar A, Devendrakumar C, Vibhuti M, Neelam S, Vinatzer BA. Diversity of Ralstonia solanacearum Strains on the Andaman Islands in India. PLANT DISEASE 2016; 100:732-738. [PMID: 30688609 DOI: 10.1094/pdis-03-15-0258-re] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Fourteen Ralstonia solanacearum strains from solanaceous vegetables on the Andaman Islands, India, were characterized using a polyphasic approach. The strains wilted their respective hosts within 1 to 3 weeks postinoculation. Virulence assays on tomato (Solanum lycopersicum), brinjal (eggplant; S. melongena), and chili pepper (Capsicum annuum) revealed that all strains were infective on all three hosts. However, tomato was more susceptible than eggplant and chili pepper. Strains were identified as R. solanacearum based on carbon substrate utilization profiling with Biolog similarity coefficients >0.82. Species identity was further confirmed by 16S ribosomal RNA and recN gene sequence analysis. Intraspecific identification of strains revealed the presence of race 1 biovar 3 and race 1 biovar 4. Both biovars wilted plants with similar aggressiveness. All strains were identified as phylotype I, and multilocus sequence typing revealed that the strains belong to a small number of clonal complexes that also comprise strains from mainland India, especially West Bengal state and Kerala.
Collapse
Affiliation(s)
- K Sakthivel
- Division of Field Crop Improvement and Protection, Central Island Agricultural Research Institute, Port Blair 744 101, Andaman and Nicobar Islands, India
| | - R K Gautam
- Division of Field Crop Improvement and Protection, Central Island Agricultural Research Institute, Port Blair 744 101, Andaman and Nicobar Islands, India
| | - K Kumar
- Division of Field Crop Improvement and Protection, Central Island Agricultural Research Institute, Port Blair 744 101, Andaman and Nicobar Islands, India
| | - S Dam Roy
- Division of Field Crop Improvement and Protection, Central Island Agricultural Research Institute, Port Blair 744 101, Andaman and Nicobar Islands, India
| | - A Kumar
- Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi 110 012, India
| | - C Devendrakumar
- Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi 110 012, India
| | - M Vibhuti
- Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi 110 012, India
| | - S Neelam
- Division of Plant Pathology, Indian Agricultural Research Institute, New Delhi 110 012, India
| | - B A Vinatzer
- Department of Plant Pathology, Physiology, and Weed Science, Virginia Tech, Blacksburg 24061
| |
Collapse
|
28
|
Tran TM, Jacobs JM, Huerta A, Milling A, Weibel J, Allen C. Sensitive, Secure Detection of Race 3 Biovar 2 and Native U.S. Strains of Ralstonia solanacearum. PLANT DISEASE 2016; 100:630-639. [PMID: 30688589 DOI: 10.1094/pdis-12-14-1327-re] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Detecting and correctly identifying Ralstonia solanacearum in infected plants is important because the race 3 biovar 2 (R3bv2) subgroup is a high-concern quarantine pathogen, while the related sequevar 7 group is endemic to the southeastern United States. Preventing accidental import of R3bv2 in geranium cuttings demands sensitive detection methods that are suitable for large-volume use both onshore and offshore. However, detection is complicated by frequent asymptomatic latent infections, uneven pathogen distribution within infected plants, pathogen viable-but-not-culturable state, and biosecurity laws that restrict transport of R3bv2 strains for diagnosis. There are many methods to detect R3bv2 strains but their relative utility is unknown, particularly in the realistic context of infected plant hosts. Therefore, we compared the sensitivity, cost, and technical complexity of several assays to detect and distinguish R3bv2 and sequevar 7 strains of R. solanacearum in geranium, tomato, and potato tissue in the laboratory and in naturally infected tomato plants from the field. The sensitivity of polymerase chain reaction (PCR)-based methods in infected geranium tissues was significantly improved by use of Kapa3G Plant, a polymerase with enhanced performance in the presence of plant inhibitors. R3bv2 cells were killed within 60 min of application to Whatman FTA(R) nucleic acid-binding cards, suggesting that samples on FTA cards can be safely transported for diagnosis. Overall, culture enrichment followed by dilution plating was the most sensitive detection method (101 CFU/ml) but it was also most laborious. Conducting PCR from FTA cards was faster, easier, and sensitive enough to detect approximately 104 CFU/ml, levels similar to those found in latently infected geranium plants.
Collapse
Affiliation(s)
- Tuan Minh Tran
- Department of Plant Pathology, University of Wisconsin-Madison 53706
| | - Jonathan M Jacobs
- Department of Plant Pathology, University of Wisconsin-Madison 53706
| | - Alejandra Huerta
- Department of Plant Pathology, University of Wisconsin-Madison 53706
| | - Annett Milling
- Department of Plant Pathology, University of Wisconsin-Madison 53706
| | - Jordan Weibel
- Department of Plant Pathology, University of Wisconsin-Madison 53706
| | - Caitilyn Allen
- Department of Plant Pathology, University of Wisconsin-Madison 53706
| |
Collapse
|
29
|
Castillo JA, Plata G. The expansion of brown rot disease throughout Bolivia: possible role of climate change. Can J Microbiol 2016; 62:442-8. [PMID: 26991236 DOI: 10.1139/cjm-2015-0665] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
Bacterial wilt is a devastating plant disease caused by the bacterial pathogen Ralstonia solanacearum species complex and affects different crops. Bacterial wilt infecting potato is also known as brown rot (BR) and is responsible for significant economic losses in potato production, especially in developing countries. In Bolivia, BR affects up to 75% of the potato crop in areas with high incidence and 100% of stored potatoes. The disease has disseminated since its introduction to the country in the mid-1980s mostly through contaminated seed tubers. To avoid this, local farmers multiply seed tubers in highlands because the strain infecting potatoes cannot survive near-freezing temperatures that are typical in the high mountains. Past disease surveys have shown an increase in seed tubers with latent infection in areas at altitudes lower than 3000 m a.s.l. Since global warming is increasing in the Andes Mountains, in this work, we explored the incidence of BR in areas at altitudes above 3000 m a.s.l. Results showed BR presence in the majority of these areas, suggesting a correlation between the increase in disease incidence and the increase in temperature and the number of irregular weather events resulting from climate change. However, it cannot be excluded that the increasing availability of latently infected seed tubers has boosted the spread of BR.
Collapse
Affiliation(s)
- José Antonio Castillo
- Fundación PROINPA, P.O. Box 4285, Av. Meneces Km 4, El Paso, Cochabamba, Bolivia.,Fundación PROINPA, P.O. Box 4285, Av. Meneces Km 4, El Paso, Cochabamba, Bolivia
| | - Giovanna Plata
- Fundación PROINPA, P.O. Box 4285, Av. Meneces Km 4, El Paso, Cochabamba, Bolivia.,Fundación PROINPA, P.O. Box 4285, Av. Meneces Km 4, El Paso, Cochabamba, Bolivia
| |
Collapse
|
30
|
Pensec F, Lebeau A, Daunay MC, Chiroleu F, Guidot A, Wicker E. Towards the Identification of Type III Effectors Associated with Ralstonia solanacearum Virulence on Tomato and Eggplant. PHYTOPATHOLOGY 2015; 105:1529-44. [PMID: 26368514 DOI: 10.1094/phyto-06-15-0140-r] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/21/2023]
Abstract
For the development of pathogen-informed breeding strategies, identifying the microbial genes involved in interactions with the plant is a critical step. To identify type III effector (T3E) repertoires associated with virulence of the bacterial wilt pathogen Ralstonia solanacearum on Solanaceous crops, we used an original association genetics approach combining DNA microarray data and pathogenicity data on resistant eggplant, pepper, and tomato accessions. From this first screen, 25 T3Es were further full-length polymerase chain reaction-amplified within a 35-strain field collection, to assess their distribution and allelic diversity. Six T3E repertoire groups were identified, within which 11 representative strains were chosen to challenge the bacterial wilt-resistant egg plants 'Dingras multiple Purple' and 'AG91-25', and tomato Hawaii 7996. The virulence or avirulence phenotypes could not be explained by specific T3E repertoires, but rather by individual T3E genes. We identified seven highly avirulence-associated genes, among which ripP2, primarily referenced as conferring avirulence to Arabidopsis thaliana. Interestingly, no T3E was associated with avirulence to both egg-plants. Highly virulence-associated genes were also identified: ripA5_2, ripU, and ripV2. This study should be regarded as a first step toward investigating both avirulence and virulence function of the highlighted genes, but also their evolutionary dynamics in natural R. solanacearum populations.
Collapse
Affiliation(s)
- Flora Pensec
- First, second, fourth, and sixth authors: CIRAD, UMR 53 Peuplements Végétaux et Bioagresseurs en Milieu Tropical (PVBMT), Saint-Pierre, La Réunion, France; third author: INRA, Centre d'Avignon, Unité de Génétique et Amélioration des Fruits et Légumes, UR1052, Montfavet, France; and fifth author: INRA, UMR 441 Laboratoire des Interactions Plantes-Microorganismes (LIPM), Castanet-Tolosan, France. Current address of first author: Institut National de la Recherche Agronomique, UMR A 1131 Santé de la Vigne et Qualité du Vin (SVQV), Colmar, France. Université de Strasbourg, Strasbourg, France
| | - Aurore Lebeau
- First, second, fourth, and sixth authors: CIRAD, UMR 53 Peuplements Végétaux et Bioagresseurs en Milieu Tropical (PVBMT), Saint-Pierre, La Réunion, France; third author: INRA, Centre d'Avignon, Unité de Génétique et Amélioration des Fruits et Légumes, UR1052, Montfavet, France; and fifth author: INRA, UMR 441 Laboratoire des Interactions Plantes-Microorganismes (LIPM), Castanet-Tolosan, France. Current address of first author: Institut National de la Recherche Agronomique, UMR A 1131 Santé de la Vigne et Qualité du Vin (SVQV), Colmar, France. Université de Strasbourg, Strasbourg, France
| | - M C Daunay
- First, second, fourth, and sixth authors: CIRAD, UMR 53 Peuplements Végétaux et Bioagresseurs en Milieu Tropical (PVBMT), Saint-Pierre, La Réunion, France; third author: INRA, Centre d'Avignon, Unité de Génétique et Amélioration des Fruits et Légumes, UR1052, Montfavet, France; and fifth author: INRA, UMR 441 Laboratoire des Interactions Plantes-Microorganismes (LIPM), Castanet-Tolosan, France. Current address of first author: Institut National de la Recherche Agronomique, UMR A 1131 Santé de la Vigne et Qualité du Vin (SVQV), Colmar, France. Université de Strasbourg, Strasbourg, France
| | - Frédéric Chiroleu
- First, second, fourth, and sixth authors: CIRAD, UMR 53 Peuplements Végétaux et Bioagresseurs en Milieu Tropical (PVBMT), Saint-Pierre, La Réunion, France; third author: INRA, Centre d'Avignon, Unité de Génétique et Amélioration des Fruits et Légumes, UR1052, Montfavet, France; and fifth author: INRA, UMR 441 Laboratoire des Interactions Plantes-Microorganismes (LIPM), Castanet-Tolosan, France. Current address of first author: Institut National de la Recherche Agronomique, UMR A 1131 Santé de la Vigne et Qualité du Vin (SVQV), Colmar, France. Université de Strasbourg, Strasbourg, France
| | - Alice Guidot
- First, second, fourth, and sixth authors: CIRAD, UMR 53 Peuplements Végétaux et Bioagresseurs en Milieu Tropical (PVBMT), Saint-Pierre, La Réunion, France; third author: INRA, Centre d'Avignon, Unité de Génétique et Amélioration des Fruits et Légumes, UR1052, Montfavet, France; and fifth author: INRA, UMR 441 Laboratoire des Interactions Plantes-Microorganismes (LIPM), Castanet-Tolosan, France. Current address of first author: Institut National de la Recherche Agronomique, UMR A 1131 Santé de la Vigne et Qualité du Vin (SVQV), Colmar, France. Université de Strasbourg, Strasbourg, France
| | - Emmanuel Wicker
- First, second, fourth, and sixth authors: CIRAD, UMR 53 Peuplements Végétaux et Bioagresseurs en Milieu Tropical (PVBMT), Saint-Pierre, La Réunion, France; third author: INRA, Centre d'Avignon, Unité de Génétique et Amélioration des Fruits et Légumes, UR1052, Montfavet, France; and fifth author: INRA, UMR 441 Laboratoire des Interactions Plantes-Microorganismes (LIPM), Castanet-Tolosan, France. Current address of first author: Institut National de la Recherche Agronomique, UMR A 1131 Santé de la Vigne et Qualité du Vin (SVQV), Colmar, France. Université de Strasbourg, Strasbourg, France
| |
Collapse
|
31
|
Zhang Y, Qiu S. Phylogenomic analysis of the genus Ralstonia based on 686 single-copy genes. Antonie van Leeuwenhoek 2015; 109:71-82. [PMID: 26494208 DOI: 10.1007/s10482-015-0610-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/26/2015] [Accepted: 10/16/2015] [Indexed: 12/11/2022]
Abstract
The genus Ralstonia contains species that are devastating plant pathogens, opportunistic human pathogens, and/or important degraders of xenobiotic and recalcitrant compounds. However, significant nomenclature problems exist, especially for the Ralstonia solanacearum species complex which consists of four phylotypes. Phylogenomics of the Ralstonia genus was investigated via a comprehensive analysis of 39 Ralstonia genomes as well as four genomes of Cupriavidus necator (more commonly known by its previous name Ralstonia eutropha). These data revealed 686 single-copy orthologs that could be extracted from the Ralstonia core-genome and used to reconstruct the phylogeny of the genus Ralstonia. The generated tree has strong bootstrap support for almost all branches. We also estimated the in silico DNA-DNA hybridization (isDDH) and the average nucleotide identity (ANI) values between each genome. Our data confirmed that whole genome sequence data provides a powerful tool to resolve the complex taxonomic questions of the genus Ralstonia, e.g. strains of Ralstonia solanacearum phylotype IIA and IIB may represent two subspecies of R. solanacearum, and strains of R. solanacearum phylotype I and III may be classified into two subspecies of Ralstonia pseudosolanacearum. Recently, strains of R. solanacearum phylotype IV were proposed to be reclassified into different subspecies of Ralstonia syzygii; our study, however, showed that phylotype IV strains had high isDDH values (83.8-96.1 %), indicating it may be not appropriate to classify these closely related strains into different subspecies. We also evaluated the performance of six chromosomal housekeeping genes (gdhA, mutS, adk, leuS, rplB and gyrB) used in Ralstonia phylogenetic inference. The multilocus sequence analysis of these six marker genes was able to reliably infer the phylogenetic relationships of the genus Ralstonia.
Collapse
Affiliation(s)
- Yucheng Zhang
- Department of Plant Pathology, University of Florida, Gainesville, FL, 32611, USA.
| | - Sai Qiu
- Department of Nematology and Entomology, University of Florida, Gainesville, FL, 32611, USA
| |
Collapse
|
32
|
Aritua V, Harrison J, Sapp M, Buruchara R, Smith J, Studholme DJ. Genome sequencing reveals a new lineage associated with lablab bean and genetic exchange between Xanthomonas axonopodis pv. phaseoli and Xanthomonas fuscans subsp. fuscans. Front Microbiol 2015; 6:1080. [PMID: 26500625 PMCID: PMC4595841 DOI: 10.3389/fmicb.2015.01080] [Citation(s) in RCA: 18] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2015] [Accepted: 09/22/2015] [Indexed: 11/13/2022] Open
Abstract
Common bacterial blight is a devastating seed-borne disease of common beans that also occurs on other legume species including lablab and Lima beans. We sequenced and analyzed the genomes of 26 strains of Xanthomonas axonopodis pv. phaseoli and X. fuscans subsp. fuscans, the causative agents of this disease, collected over four decades and six continents. This revealed considerable genetic variation within both taxa, encompassing both single-nucleotide variants and differences in gene content, that could be exploited for tracking pathogen spread. The bacterial strain from Lima bean fell within the previously described Genetic Lineage 1, along with the pathovar type strain (NCPPB 3035). The strains from lablab represent a new, previously unknown genetic lineage closely related to strains of X. axonopodis pv. glycines. Finally, we identified more than 100 genes that appear to have been recently acquired by Xanthomonas axonopodis pv. phaseoli from X. fuscans subsp. fuscans.
Collapse
Affiliation(s)
- Valente Aritua
- International Center for Tropical Agriculture Kampala, Uganda
| | | | | | - Robin Buruchara
- Africa Regional Office, International Center for Tropical Agriculture, Consultative Group for International Agricultural Research (CGIAR) Nairobi, Kenya
| | | | | |
Collapse
|