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Xanthomonas arboricola comprises a number of economically important fruit tree pathogens classified within different pathovars. Dozens of nonpathogenic and taxonomically unvalidated strains are also designated as X. arboricola, leading to a complicated taxonomic status in the species. In this study, we have evaluated the whole-genome resources of all available Xanthomonas spp. strains designated as X. arboricola in the public databases to refine the members of the species based on DNA similarity indexes and core genome-based phylogeny. Our results show that, of the nine validly described pathovars within X. arboricola, pathotype strains of seven pathovars are taxonomically genuine, belonging to the core clade of the species regardless of their pathogenicity on the host of isolation (thus the validity of pathovar status). However, strains of X. arboricola pv. guizotiae and X. arboricola pv. populi do not belong to X. arboricola because of the low DNA similarities between the type strain of the species and the pathotype strains of these two pathovars. Thus, we propose to elevate the two pathovars to the rank of a species as X. guizotiae sp. nov. with the type strain CFBP 7408T and X. populina sp. nov. with the type strain CFBP 3123T. In addition, other mislabeled strains of X. arboricola were scattered within Xanthomonas spp. that belong to previously described species or represent novel species that await formal description., Iran National Science Foundation Grant/Award Number: 99017084 Shiraz University Iranian Ministry of Science and Technology. University of Tehran Grant/Award Number: 1400-223

Agrobacterium tumefaciens species complex contains a set of diverse bacterial strains, most of which are well known for their pathogenicity on agricultural plants causing crown gall diseases. Members of A. tumefaciens species complex are classified into several taxonomically distinct lineages called “genomospecies” (13 genomospecies until early 2021). Recently, two genomospecies, G19 (strains RnrT, Rew, and Rnw) and G20 (strains OT33T and R13) infecting Rosa sp. plants in Iran, were described based on biochemical and molecular-phylogenetic data. Whole genome sequence-based core-genome phylogeny followed by average nucleotide identity (ANI) and digital DNA-DNA hybridization (dDDH) calculations performed in this study suggested that genomospecies G19 and G20 could be described as two novel and standalone species. In the phylogenetic tree, these two new genomospecies were clustered separately from other genomospecies/species of A. tumefaciens species complex. Moreover, both ANI and dDDH indices between the G19/G20 strains and other Rhizobiaceae members are clearly below the accepted thresholds for prokaryotic species description. Hence, Agrobacterium burrii sp. nov. is proposed to encompass the G19 strains, with RnrT = CFBP 8705T = DSM 112541T as type strain. Agrobacterium shirazense sp. nov. is also proposed to include G20 strains, with OT33T = CFBP 8901T = DSM 112540T as type strain. [Formula: see text] Copyright © 2022 The Author(s). This is an open access article distributed under the CC BY 4.0 International license .

Bacterial leaf streak of small-grain cereals is an economically important disease of wheat and barley crops. The disease occurs in many countries across the globe, with a particular importance in regions characterized by high precipitations or the areas where sprinkler irrigation is used. Three genetically distinct lineages of the Gram-negative bacterium Xanthomonas translucens i.e. X. translucens pv. undulosa, X. translucens pv. translucens, and X. translucens pv. cerealis are responsible for most of the bacterial leaf streak infections on wheat and barley crops. Considering the seed-borne nature of the pathogens, they are included in the A2 (high-risk) list of quarantine organisms for some European countries; hence, they are under strict quarantine control and zero tolerance. Due to the taxonomic complexities within X. translucens, the exact geographic distribution of each pathovar has not yet been determined. In this mini-review, we provide an updated overview on the detection and diagnosis of the bacterial leaf streak pathogens. First, a short history of the leaf streak pathogens is provided, followed by symptomology and host range of the causal agents. Then, the utility of conventional methods and high throughput molecular approaches in the precise detection and identification of the pathogens is explained. Finally, we highlight the role of quarantine inspections and early detection of the pathogen in combating the risk of bacterial leaf streak in the 21st century’s small-grains cereals’ industry.

Bacterial leaf streak (BLS) primarily affects barley and wheat and is mainly caused by the pathogens Xanthomonas translucens pv. translucens and X. translucens pv. undulosa, respectively. BLS is distributed globally and poses a risk to food security and the supply of malting barley. X. translucens pv. cerealis can infect both wheat and barley but is rarely isolated from these hosts in natural infections. These pathogens have undergone a confusing taxonomic history and the biology has been poorly understood making it difficult to develop effective control measures. Recent advancements in the ability and accessibility to sequence bacterial genomes have shed light on phylogenetic relationships between strains and identified genes that may play a role in virulence, such as those that encode Type III effectors. In addition, sources of resistance to BLS have been identified in barley and wheat lines and ongoing efforts are being made to map these genes and evaluate germplasm. While there are still gaps in BLS research, progress has been made in recent years to further understand epidemiology, diagnostics, pathogen virulence, and host resistance.

Bacterial leaf streak disease caused by Xanthomonas translucens pv. undulosa is an economically important disease threatening wheat and barley crops around the globe. So far, specific PCR-based detection and identification tests for X. translucens pathovars are not available. In this study, we used comparative genomics approach to design a pathovar-specific primer pair for detection of X. translucens pv. undulosa in naturally infected seeds and its differentiation from other pathovars of the species. For this aim, complete genome sequences of strains of different X. translucens pathovars were compared and the specific PCR primer pair XtuF/XtuR was designed. These primers were strictly specific to X. translucens pv. undulosa as the expected 229 bp DNA fragment was not amplified in the closely-related pathovars nor in other xanthomonads, wheat pathogenic bacteria, and other plant pathogenic bacteria. High sensitivity of the primer pair XtuF/XtuR allowed detection of pure DNA of the pathogen in a concentration as low as 4.5 pg/µl. The pathogen was also detected in water suspension at a concentration of 8.6 × 102 cfu/ml. The PCR test was capable of detecting the pathogen in extracts of naturally infected wheat seeds at a concentration of 3.5 × 104 cfu/g while culture plate method was able to detect the pathogen at a concentration of 50 × 105 cfu/g of the same seeds. The PCR test developed in this study is a step forward for precise detection and identification of X. translucens pv. undulosa to prevent outbreaks of the bacterial leaf streak disease.

Disease symptoms Symptoms include water‐soaked areas surrounded by chlorosis turning into necrotic spots on all aerial parts of plants. On tomato fruits, small, water‐soaked, or slightly raised pale‐green spots with greenish‐white halos are formed, ultimately becoming dark brown and slightly sunken with a scabby or wart‐like surface. Host range Main and economically important hosts include different types of tomatoes and peppers. Alternative solanaceous and nonsolanaceous hosts include Datura spp., Hyoscyamus spp., Lycium spp., Nicotiana rustica, Physalis spp., Solanum spp., Amaranthus lividus, Emilia fosbergii, Euphorbia heterophylla, Nicandra physaloides, Physalis pubescens, Sida glomerata, and Solanum americanum. Taxonomic status of the pathogen Domain, Bacteria; phylum, Proteobacteria; class, Gammaproteobacteria; order, Xanthomonadales; family, Xanthomonadaceae; genus, Xanthomonas; species, X. euvesicatoria, X. hortorum, X. vesicatoria. Synonyms (nonpreferred scientific names) Bacterium exitiosum, Bacterium vesicatorium, Phytomonas exitiosa, Phytomonas vesicatoria, Pseudomonas exitiosa, Pseudomonas gardneri, Pseudomonas vesicatoria, Xanthomonas axonopodis pv. vesicatoria, Xanthomonas campestris pv. vesicatoria, Xanthomonas cynarae pv. gardneri, Xanthomonas gardneri, Xanthomonas perforans. Microbiological properties Colonies are gram‐negative, oxidase‐negative, and catalase‐positive and have oxidative metabolism. Pale‐yellow domed circular colonies of 1–2 mm in diameter grow on general culture media. Distribution The bacteria are widespread in Africa, Brazil, Canada and the USA, Australia, eastern Europe, and south‐east Asia. Occurrence in western Europe is restricted. Phytosanitary categorization A2 no. 157, EU Annex designation II/A2. EPPO codes XANTEU, XANTGA, XANTPF, XANTVE., In this review we provide a historical perspective as well as an updated overview on the aetiology, epidemiology, and management strategies of bacterial spot of tomato and pepper.

Mycopathogenic bacteria play a pivotal role in the productivity of edible mushrooms grown under controlled conditions. In this study, we carried out a comprehensive farm survey and sampling (2018 to 2021) on button mushroom ( Agaricus bisporus) farms in 15 provinces in Iran to monitor the status of bacterial pathogens infecting the crop. Mycopathogenic bacterial strains were isolated from pins, stems, and caps, as well as the casing layer on 38 mushroom farms. The bacterial strains incited symptoms on mushroom caps ranging from faint discoloration to dark brown and blotch of the inoculated surfaces. Among the bacterial strains inciting disease symptoms on bottom mushroom, 40 were identified as Ewingella americana based on biochemical assays and phylogeny of 16S rRNA and the gyrB gene. E. americana strains differed in their aggressiveness on mushroom caps and stipes, where the corresponding symptoms ranged from deep yellow to dark brown. In the phylogenetic analyses, all E. americana strains isolated in this study were clustered in a monophyletic clade closely related to the nonpathogenic and environmental strains of the species. BOX-PCR-based fingerprinting revealed intraspecific diversity. Using the cutoff level of 73 to 76% similarity, the strains formed six clusters. A chronological pattern was observed, where the strains isolated in 2018 were differentiated from those isolated in 2020 and 2021. Taken together, due to the multifaceted nature of the pathogen, such a widespread occurrence of E. americana on mushroom farms in Iran could be an emerging threat for the mushroom industry in the country.

Goss's bacterial wilt and leaf blight of maize (Zea mays) caused by the gram-positive coryneform bacterium Clavibacter nebraskensis is an economically important disease in North America. C. nebraskensis is included within the high-risk list of quarantine pathogens by several plant protection organizations (EPPO code: CORBMI), hence it is under strict quarantine control around the world. The causal agent was reported for the first time on maize in Nebraska (USA) in 1969. After an outbreak during the 1970s, prevalence of the disease decreased in the 1980s to the early 2000s, before the disease resurged causing a serious threat to maize production in North America. The re-emergence of Goss's wilt in the corn belt of the United States led to several novel achievements in understanding the pathogen biology and disease control. In this review, we provide an updated overview of the pathogen taxonomy, biology, and epidemiology as well as management strategies of Goss's wilt disease. First, a taxonomic history of the pathogen is provided followed by symptomology and host range, genetic diversity, and pathogenicity mechanisms of the bacterium. Then, utility of high-throughput molecular approaches in the precise detection and identification of the pathogen and the management strategies of the disease are explained. Finally, we highlight the role of integrated pest management strategies to combat the risk of Goss's wilt in the 21st century maize industry.Large (2-15 cm) tan to grey elongated oval lesions with wavy, irregular water-soaked margins on the leaves. The lesions often start at the leaf tip or are associated with wounding caused by hail or wind damage. Small (1 mm in diameter), dark, discontinuous water-soaked spots, known as "freckles", can be observed in the periphery of lesions. When backlit, the freckles appear translucent. Early infection (prior to growth stage V6) may become systemic and cause seedlings to wilt, wither, and die. Coalescence of lesions results in leaf blighting.Maize (Zea mays) is the only economic host of the pathogen. A number of Poaceae species are reported to act as secondary hosts for C. nebraskensis.Class: Actinobacteria; Order: Micrococcales; Family: Microbacteriaceae; Genus: Clavibacter; Species: Clavibacter nebraskensis.Corynebacterium nebraskense (Schuster, 1970) VidaverMandel 1974; Corynebacterium michiganense pv. nebraskense (VidaverMandel 1974) DyeKemp 1977; Corynebacterium michiganense subsp. nebraskense (VidaverMandel 1974) CarlsonVidaver 1982; Clavibacter michiganense subsp. nebraskense (VidaverMandel 1974) Davis et al. 1984; Clavibacter michiganensis subsp. nebraskensis (VidaverMandel 1974) Davis et al. 1984.ATCC 27794Cells are gram-positive, orange-pigmented, pleomorphic club- or rod-shaped, nonspore-forming, nonmotile, and without flagella, approximately 0.5 × 1-2.0 μm.The pathogen is restricted to Canada and the United States.EPPO code CORBNE.

The genus Xanthomonas contains a set of diverse bacterial strains, most of which are known for their pathogenicity on annual crops and fruit trees causing economically important plant diseases. Recently, five Xanthomonas strains were isolated from Agrobacterium -induced crown gall tissues of amaranth (Amaranthus sp.) and weeping fig (Ficus benjamina) plants in Iran. Phenotypic characteristics (i.e. biochemical tests and pathogenicity features) and whole genome sequence-based core-genome phylogeny followed by average nucleotide identity and digital DNA–DNA hybridization calculations suggested that these gall-associated strains belong to two new species within the genus Xanthomonas . In this study, we provide a formal species description for these new species where Xanthomonas bonasiae sp. nov. is proposed for the strains isolated from weeping fig with FX4T (=CFBP 8703T=DSM 112530T) as type strain. The name Xanthomonas youngii sp. nov. is proposed for the strains isolated from amaranth with AmX2T (=CFBP 8902T=DSM 112529T) as type strain.

Bacterial wilt of dry beans (family Fabaceae) caused by the actinobacterial agent Curtobacterium flaccumfaciens pv. flaccumfaciens is one of the most important diseases threatening edible legume production around the globe. Despite the economic losses due to the bacterial wilt disease, the pathogen has not so far been investigated for its genomic features, pathogenicity determinants, and virulence strategies. Here we present the first complete genome sequence of a highly virulent bacteriocin-producing C. flaccumfaciens pv. flaccumfaciens strain P990. The bacterium has a circular chromosome consisting of 3,736 kbp with the G+C% content of 71.0%. Furthermore, a 147-kbp circular plasmid (pCff1) with 66.1% G+C% content as well as two circular plasmid-like DNAs with sizes of 25 and 22 kbp were detected within the genomic contents of C. flaccumfaciens pv. flaccumfaciens. Phylogenetic analyses revealed that only a few number of Curtobacterium sp. strains deposited in the public databases could be classified within the species C. flaccumfaciens. Comparative genomics of C. flaccumfaciens pv. flaccumfaciens using the genome sequences of actinobacterial plant pathogens revealed the presence of a set of unique low G+C% content genomic islands in the C. flaccumfaciens pv. flaccumfaciens genome. Homologs of pathogenicity-determinant loci capable of producing 1,4-beta-xylanase (xysA), pectate lyase (pelA1 and pelA2), serine protease (chpC, chpG, and pat-1), and sortase (srtA) were detected in C. flaccumfaciens pv. flaccumfaciens genome. The genomic data presented here extend our understanding of the C. flaccumfaciens pv. flaccumfaciens genomic features and pave the ways of research on functional and interaction genetics to combat the risk of bacterial wilt disease in the 21st century’s dry bean industry.

From September to December 2018, commercial button mushroom (Agaricus bisporus) farms in central Iran were surveyed to monitor the causal agent(s) of browning and blotch symptoms on mushroom caps. In addition to dozens of pseudomonads (i.e., Pseudomonas tolaasii and Pseudomonas reactans), six slow-growing gram-positive bacterial strains were isolated from blotched mushroom caps. These bacteria presented as creamy white, circular, smooth, nonfluorescent, and shiny colonies with whole margins resembling members of Microbacteriaceae (Actinobacteria). All of the actinobacterial strains were aggressively pathogenic on cut cap surface of two edible mushrooms (i.e., A. bisporus and Pleurotus eryngii), inducing brown pit symptoms 48 h postinoculation. The strains did not induce symptoms on the vegetables tested (i.e., carrot, cucumber, and potato), and they did not affect the growth of mycelium of tested plant-pathogenic fungi (i.e., Acremonium sp., Fusarium spp., and Phytopythium sp.). Phylogeny of 16S ribosomal RNA and multilocus sequence analysis of six housekeeping genes (i.e., atpD, dnaK, gyrB, ppK, recA, and rpoB) revealed that the bacterial strains belong to the actinobacterial genus Mycetocola spp., whereas the species status of the strains remains undetermined. Mushroom-associated Mycetocola species were previously reported to be capable of detoxifying tolaasin, a toxin produced by P. tolaasii, whereas the strains isolated in this study did not show tolaasin detoxification activities. Altogether, this is the first report of a mushroom disease caused by an actinobacterial species, and “bacterial brown pit” was assigned as the common name of the disease.

Bacterial leaf streak caused by different pathovars of Xanthomonas translucens is the most important seedborne bacterial disease of small grain cereals. However, variations in the virulence-associated genomic areas of the pathogen remain uninvestigated. In this study, the diversity of transcription activator-like effectors (TALE) was investigated using the Southern blotting of BamHI-digested genomic DNAs in the Iranian strains of X. translucens. All 65 X. translucens strains were assigned into 13 genotypes, where 57 X. translucens pv. undulosa strains were placed in genotypes 1 to 8, and seven X. translucens pv. translucens strains were placed in genotypes 9 to 12. Interestingly, we did not find any TALE genes in the strain XtKm7 (genotype 13), which showed to be pathogenic only on barley. Virulence and aggressiveness of these strains in greenhouse conditions were in agreement with the TALE-based clustering of the strains in the pathovar level, though variations were observed in the aggressiveness of X. translucens pv. undulosa strains. In general, strains containing higher numbers of putative TALE genes were more virulent on wheat and barley than strains containing fewer. This is the first TALE-based genetic diversity analysis on X. translucens strains and provides novel insights into the virulence repertories and genomic characteristics of the pathogen. Further investigations using TALE mutagenesis and complementation analysis are warranted to precisely elucidate the role of each detected X. translucens TALE in bacterial virulence and aggressiveness either on wheat or barley.

Bacterial wilt and tan spot of dry beans (family Fabaceae), caused by Curtobacterium flaccumfaciens pv. flaccumfaciens, is an important emerging disease threatening the edible legume industry around the globe. The management of bacterial wilt has been a major problem since its original description in 1922. This is in part due to the seedborne nature of the pathogen allowing the bacterium to be transmitted long distances via infected seeds, as well as a lack of detailed molecular information concerning the pathogenicity repertoires and virulence determinates of the pathogen. Identification can also be difficult owing to the presence of five different colony colour variants (i.e., yellow, orange, pink, purple, and red) on culture media. In this review, we provide an overview of the aetiology, epidemiology, and management strategies of bacterial wilt disease. First, a comprehensive and comparative symptomology of the disease on different dry bean species is described. Then, the taxonomic history of the causal agent and utility of high‐throughput sequencing‐based approaches in the precise characterization of the pathogen is explained. Furthermore, we provide an updated outline on the global distribution of the pathogen, highlighting expansion of the causal agent into the areas with no history of the disease until the beginning of the current century. Finally, because there are limited options for use of conventional pesticides against the pathogen, we highlight the use of integrated pest management strategies, for example quarantine inspections, resistant cultivars, and crop sanitation, to combat the risk of bacterial wilt disease in the dry bean industry. Disease symptoms Interveinal chlorosis on leaflets leading to necrotic areas and systemic wilt. Seed discolouration to yellow, orange, pink, or purple is seen in white‐seeded cultivars. Host range Causes bacterial wilt and tan spot disease on edible dry beans in the Fabaceae family, including common bean (Phaseolus vulgaris), cowpea (Vigna unguiculata), mungbean (Vigna radiata), soybean (Glycine max), as well as a number of weed species. Taxonomic status of the pathogen Bacteria; phylum Actinobacteria; order Actinomycetales; suborder: Micrococcineae; family Microbacteriaceae; genus Curtobacterium; species Curtobacterium flaccumfaciens. Synonyms Corynebacterium flaccumfaciens subsp. flaccumfaciens; Corynebacterium flaccumfaciens pv. flaccumfaciens, Corynebacterium flaccumfaciens, Phytomonas flaccumfaciens, Bacterium flaccumfaciens. Microbiological properties Multicoloured (yellow, orange, pink, purple, and red), gram‐positive, aerobic, curved rod, nonspore‐forming, polar flagellated, motile cells. Distribution Widespread in America (Brazil, Canada, and the USA), Australia, and Iran. Restricted occurrence in Africa and Europe. Phytosanitary categorization EPPO A2 list no. 48, EU Annex II⁄B.

Background: Bacterial ring rot of potato (Solanum tuberosum) caused by the gram- positive coryneform bacterium Clavibacter sepedonicus is an important quarantine dis-ease threatening the potato industry around the globe. Since its original description in 1906 in Germany, management of ring rot has been a major problem due to the seed-borne nature (via seed tubers not true seeds) of the pathogen allowing the bacterium to be transmitted long distances via infected tubers.Disease symptoms: On growing potato plants: interveinal chlorosis on leaflets leading to necrotic areas and systemic wilt. On infected tubers: vascular tissues become yel-lowish brown with a cheesy texture due to bacterial colonization and decay.Host range: Potato is the main host of the pathogen, but natural infection also occurs on eggplant, tomato, and sugar beet.Taxonomic status of the pathogen: Class: Actinobacteria; Order: Actinomycetales; Family: Microbacteriaceae; Genus: Clavibacter; Species: Clavibacter sepedonicus(Spieckermann and Kotthoff 1914) Li et al. 2018.Synonyms (nonpreferred scientific names): Aplanobacter sepedonicus; Bacterium sepe-donicum; Corynebacterium sepedonicum; Corynebacterium michiganense pv. sepedoni-cum; Clavibacter michiganensis subsp. sepedonicus.Microbiological properties: Gram- positive, club-shaped cells with creamy to yellowish-cream colonies for which the optimal growth temperature is 20–23°C.Distribution: Asia (China, Japan, Kazakhstan, Nepal, North Korea, Pakistan, South Korea, Uzbekistan, the Asian part of Russia), Europe (Belarus, Bulgaria, Czech Republic, Estonia, Finland, Georgia, Germany, Greece, Hungary, Latvia, Lithuania, Norway, Poland, Romania, European part of Russia, Slovakia, Spain, Sweden, Turkey, Ukraine), and North America (Canada, Mexico, USA).Phytosanitary categorization: CORBSE: EPPO A2 list no. 51. EU; Annex designation I/A2.

This datasheet on Clavibacter nebraskensis covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas hortorum pv. pelargonii covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Clavibacter michiganensis covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Dickeya dadantii covers Identity, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Seedborne Aspects, Impacts, Prevention/Control, Further Information.

This datasheet on Xanthomonas hortorum pv. carotae covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

Ralstonia solanacearum is included in the A2 (high risk) list of quarantine organisms by the European and Mediterranean Plant Protection Organization (EPPO). EPPO Code for R. solanacearum is RALSSO, while the phytosanitary categorization of the species in EPPO A2 list is no.58, EU: I/A2 (EPPO, 2018). Bacterial wilt disease was first reported in southern USA in the late nineteenth century on tomato plants (Smith, 1896). Infected plant materials (e.g. potato tubers) transmit the pathogen over long distances; hence, quarantine inspections and plant sanitary practices are the cornerstone of disease management (EPPO, 2018). R. solanacearum strains in the race 3 group are a select agent under the US Agricultural Bioterrorism Protection Act of 2002 (USDA, 2005). Peculiarly, the organism, if not yet already present in North America in pelargonium (Strider et al., 1981), was introduced with cuttings of this host by American companies producing these cuttings for their markets in countries like Kenya and Guatemala (Norman et al., 1999, 2009; Kim et al., 2002; Williamson et al., 2002; O'Hern, 2004). A similar situation led to introductions of the pathogen from Kenya into some northern European nurseries. Once the source (contaminated surface water) was recognized and proper control measures (use of deep soil water, disinfection of cutting producing premises and replacement of mother stock), the problem was solved and the disease in greenhouses eradicated (Janse et al., 2004). Similarly race 1 has been introduced into greenhouses with ornamental plants (rhizomes, cuttings or fully grown plants) such as Epipremnum, Anthurium, Curcuma spp. and Begonia eliator from tropical areas (Norman and Yuen, 1998, 1999; Janse et al., 2006; Janse, 2012). Introduction can and did occur from Costa Rica and the Caribbean, Indonesia, Thailand and South Africa. However, this idea of placing pathogens on bioterrorist list for unclear and perhaps industry-driven reasons and its effects, is strongly opposed in a recent publication from leading phytobacteriologists. This is because R. solanacearum is an endemic pathogen, causing endemic disease in most parts of its geographic occurrence, moreover normal quarantine regulations are already in place where the disease is not present or only sporadically and are thought to be more efficient and less damaging to trade and research than placing this pathogen on select agent lists and treating it as such (Young et al., 2008). Peculiarly, it has been used in the control of a real invasive species, the weed kahili ginger (Hedychium gardenarium) in tropical forests in Hawaii. This is not without risks because strains occurring on this weed host were thought to be non-virulent, but later appeared to be virulent on many edible and ornamental ginger species as well (Anderson and Gardner, 1999; Paret et al., 2008). Another threat for these countries could be strains belonging to race 1, biovar 1 (phylotype I) that have already been reported from field-grown potatoes in Portugal (Cruz et al., 2008).

This datasheet on Xanthomonas arboricola pv. fragariae covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Natural Enemies, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas translucens pv. undulosa covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas translucens pv. cerealis covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Acidovorax citrulli covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Vectors & Intermediate Hosts, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Natural Enemies, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas vesicatoria covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas arboricola pv. pruni covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas euvesicatoria pv. euvesicatoria covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Seedborne Aspects, Natural Enemies, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas euvesicatoria pv. perforans covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Clavibacter tessellarius covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Seedborne Aspects, Impacts, Prevention/Control, Further Information.

This datasheet on Acidovorax avenae covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Acidovorax oryzae covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Seedborne Aspects, Natural Enemies, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Ralstonia syzygii subsp. celebesensis covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Vectors & Intermediate Hosts, Diagnosis, Biology & Ecology, Seedborne Aspects, Natural Enemies, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas hortorum pv. gardneri covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas translucens pv. translucens covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas euvesicatoria pv. alfalfae covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Impacts, Prevention/Control, Further Information.

This datasheet on Dickeya solani covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Natural Enemies, Impacts, Prevention/Control, Further Information.

This datasheet on Curtobacterium flaccumfaciens pv. flaccumfaciens covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.

This datasheet on Xanthomonas arboricola pv. corylina covers Identity, Overview, Distribution, Dispersal, Hosts/Species Affected, Diagnosis, Biology & Ecology, Environmental Requirements, Seedborne Aspects, Impacts, Uses, Prevention/Control, Further Information.