Bacterial ring rot of potato caused by Clavibacter sepedonicus: A successful example of defeating the enemy under international regulations.

Background: Bacterial ring rot of potato (Solanum tuberosum) caused by the gram-positive coryneform bacterium Clavibacter sepedonicus is an important quarantine disease 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 seedborne 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.

Species of and Isolated during an Outbreak of Blackleg and Soft Rot of Potato in Northeastern and North Central United States.

An outbreak of bacterial soft rot and blackleg of potato has occurred since 2014 with the epicenter being in the northeastern region of the United States. Multiple species of and are causal agents, resulting in losses to commercial and seed potato production over the past decade in the Northeastern and North Central United States. To clarify the pathogen present at the outset of the epidemic in 2015 and 2016, a phylogenetic study was made of 121 pectolytic soft rot bacteria isolated from symptomatic potato; also included were 27 type strains of and species, and 47 historic reference strains.

pv. Identified on Common Weedy Grasses in Naturally Infected Wheat Fields in Minnesota.

Bacterial leaf streak (BLS) of wheat, caused by pv. , has been a notable disease in Minnesota wheat fields over the past decade. Potential sources of the pathogen include infested seed and crop debris.

Localized Genetic and Phenotypic Diversity of Associated With Bacterial Leaf Streak on Wheat and Barley in Minnesota.

Bacterial leaf streak (BLS) of wheat and barley has been a disease of increasing concern in the Upper Midwest over the past decade. In this study, intra- and interfield genetic and pathogenic diversity of bacteria causing BLS in Minnesota was evaluated. In 2015, 89 strains were isolated from 100 leaf samples collected from two wheat and two barley fields naturally infected with BLS.

Pantocin A, a peptide-derived antibiotic involved in biological control by plant-associated Pantoea species.

The genus Pantoea contains a broad range of plant-associated bacteria, including some economically important plant pathogens as well as some beneficial members effective as biological control agents of plant pathogens. The most well-characterized representatives of biological control agents from this genus generally produce one or more antimicrobial compounds adding to biocontrol efficacy. Some Pantoea species evaluated as biocontrol agents for fire blight disease of apple and pear produce a histidine-reversible antibiotic.

Genetic Diversity and Virulence of Wheat and Barley Strains of Xanthomonas translucens from the Upper Midwestern United States.

Bacterial leaf streak (BLS) of wheat and barley, caused by Xanthomonas translucens pv. undulosa and X. translucens pv.

Comparative Genomic Analyses of Clavibacter michiganensis subsp. insidiosus and Pathogenicity on Medicago truncatula.

Clavibacter michiganensis is the most economically important gram-positive bacterial plant pathogen, with subspecies that cause serious diseases of maize, wheat, tomato, potato, and alfalfa. Much less is known about pathogenesis involving gram-positive plant pathogens than is known for gram-negative bacteria. Comparative genome analyses of C.

PCR-Mediated Detection and Quantification of the Goss's Wilt Pathogen Clavibacter michiganensis subsp. nebraskensis Via a Novel Gene Target.

Goss's leaf blight and wilt of maize (corn) is a significant and reemerging disease caused by the bacterium Clavibacter michiganensis subsp. nebraskensis. Despite its importance, molecular tools for diagnosing and studying this disease remain limited.

Putative Serine Protease Effectors of Clavibacter michiganensis Induce a Hypersensitive Response in the Apoplast of Nicotiana Species.

Clavibacter michiganensis subspp. michiganensis and sepedonicus cause diseases on solanaceous crops. The genomes of both subspecies encode members of the pat-1 family of putative serine proteases known to function in virulence on host plants and induction of hypersensitive responses (HR) on nonhosts.

Complete Genome Sequence of Clavibacter michiganensis subsp. insidiosus R1-1 Using PacBio Single-Molecule Real-Time Technology.

We report here the complete genome sequence of Clavibacter michiganensis subsp. insidiosus R1-1, isolated in Minnesota, USA. The R1-1 genome, generated by a de novo assembly of PacBio sequencing data, is the first complete genome sequence available for this subspecies.

Characterization of the biosynthetic operon for the antibacterial peptide herbicolin in Pantoea vagans biocontrol strain C9-1 and incidence in Pantoea species.

Pantoea vagans C9-1 is a biocontrol strain that produces at least two antibiotics inhibiting the growth of Erwinia amylovora, the causal agent of fire blight disease of pear and apple. One antibiotic, herbicolin I, was purified from culture filtrates of P. vagans C9-1 and determined to be 2-amino-3-(oxirane-2,3-dicarboxamido)-propanoyl-valine, also known as N(ß)-epoxysuccinamoyl-DAP-valine.

Metabolic versatility and antibacterial metabolite biosynthesis are distinguishing genomic features of the fire blight antagonist Pantoea vagans C9-1.

Background: Pantoea vagans is a commercialized biological control agent used against the pome fruit bacterial disease fire blight, caused by Erwinia amylovora. Compared to other biocontrol agents, relatively little is currently known regarding Pantoea genetics. Better understanding of antagonist mechanisms of action and ecological fitness is critical to improving efficacy.

Genome sequence of the biocontrol agent Pantoea vagans strain C9-1.

Pantoea vagans is a Gram-negative enterobacterial plant epiphyte of a broad range of plants. Here we report the 4.89-Mb genome sequence of P.

The putative secreted serine protease Chp-7 is required for full virulence and induction of a nonhost hypersensitive response by Clavibacter michiganensis subsp. sepedonicus.

Molecular biological studies on Clavibacter michiganensis subsp. sepedonicus, the causal agent of bacterial ring rot of potato, have gained greater feasibility due to the recent availability of whole genomic sequences and genetic tools for related taxa. Here, we describe the first report of construction and characterization of a transposon (Tn) mutant library of C.

Pathogenic and Genetic Relatedness Among Xanthomonas axonopodis pv. allii and Other Pathovars of X. axonopodis.

ABSTRACT Xanthomonas axonopodis pv. allii is phenotypically and genetically diverse and its relationship to other X. axonopodis pathovars within DNA homology group 9.

Polyphasic characterization of xanthomonas strains from onion.

ABSTRACT Xanthomonas leaf blight has become an increasingly important disease of onion, but the diversity among Xanthomonas strains isolated from onion is unknown, as is their relationship to other species and pathovars of Xanthomonas. Forty-nine Xanthomonas strains isolated from onion over 27 years from 10 diverse geographic regions were characterized by pathogenicity to onion and dry bean, fatty acid profiles, substrate utilization patterns (Biolog), bactericide resistance, repetitive sequence-based polymerase chain reaction fingerprinting, rDNA internally transcribed spacer (ITS) region, and hrp b6 gene sequencing. Multiplication of onion Xanthomonas strain R-O177 was not different from X.

Genome of the actinomycete plant pathogen Clavibacter michiganensis subsp. sepedonicus suggests recent niche adaptation.

Clavibacter michiganensis subsp. sepedonicus is a plant-pathogenic bacterium and the causative agent of bacterial ring rot, a devastating agricultural disease under strict quarantine control and zero tolerance in the seed potato industry. This organism appears to be largely restricted to an endophytic lifestyle, proliferating within plant tissues and unable to persist in the absence of plant material.

Linear plasmid in the genome of Clavibacter michiganensis subsp. sepedonicus.

Contour-clamped homogeneous electric field gel analysis of genomic DNA of the plant pathogen Clavibacter michiganensis subsp. sepedonicus revealed the presence of a previously unreported extrachromosomal element. This new element was demonstrated to be a linear plasmid.

Isolation and characterization of endophytic colonizing bacteria from agronomic crops and prairie plants.

Endophytic bacteria reside within plant hosts without causing disease symptoms. In this study, 853 endophytic strains were isolated from aerial tissues of four agronomic crop species and 27 prairie plant species. We determined several phenotypic properties and found approximately equal numbers of gram-negative and gram-positive isolates.

Genomic fingerprinting of virulent and avirulent strains of Clavibacter michiganensis subspecies sepedonicus.

Genomic fingerprints of C. michiganensis subsp. sepedonicus were generated by CHEF gel electrophoresis of restriction digested high-molecular weight DNA.