Intraspecific diversity of Erwinia amylovora strains from northern Algeria.

Background: Fire blight, caused by Erwinia amylovora, is the most destructive bacterial disease affecting plants in the Rosaceae family, leading to significant economic losses. In Algeria, this disease has been reported since 2010. This study aimed to investigate the origin of fire blight in Algeria, in order to increase knowledge of the epidemiology of this serious disease and contribute to its management.

Real-time on-site detection of the three ' Liberibacter' species associated with HLB disease: a rapid and validated method.

Huanglongbing (HLB) is a devastating disease that affects all commercial citrus species worldwide. The disease is associated with bacteria of three species of the genus ' Liberibacter' transmitted by psyllid vectors. To date, HLB has no cure, so preventing its introduction into HLB-free areas is the best strategy to control its spread.

A new and accurate qPCR protocol to detect plant pathogenic bacteria of the genus 'Candidatus Liberibacter' in plants and insects.

Four pathogenic bacterial species of the genus 'Candidatus Liberibacter', transmitted by psyllid vectors, have been associated with serious diseases affecting economically important crops of Rutaceae, Apiaceae and Solanaceae families. The most severe disease of citrus plants, huanglongbing (HLB), is associated with 'Ca. Liberibacter asiaticus' (CaLas), 'Ca.

Complete Circularized Genome Resources of Seven Strains of subsp. Using Hybrid Assembly Reveals Unknown Plasmids.

is a vascular plant pathogenic bacterium native to the Americas that is causing significant epidemics and economic losses in olive and almonds in Europe, where it is a quarantine pathogen. Since its first detection in 2013 in Italy, mandatory surveys across Europe revealed the presence of the bacterium also in France, Spain, and Portugal. Combining Oxford Nanopore Technologies and Illumina sequencing data, we assembled high-quality complete genomes of seven subsp.

Infection Reshapes Microbial Composition and Network Associations in the Xylem of Almond Trees.

represents a major threat to important crops worldwide including almond, citrus, grapevine, and olives. Nowadays, there are no efficient control measures for , and the use of preventive measures and host resistance represent the most practical disease management strategies. Research on vessel-associated microorganisms is gaining special interest as an innate natural defense of plants to cope against infection by xylem-inhabiting pathogens.

Plant-associated microbiota as a source of antagonistic bacteria against the phytopathogen Erwinia amylovora.

Control of bacterial plant diseases is a major concern, as they affect economically important species and spread easily, such as the case of fire blight of rosaceous caused by Erwinia amylovora. In the search for alternatives to the use of agrochemicals and antibiotics, this work presents a screening of natural bacterial antagonists of this relevant and devastating phytopathogen. We recovered bacterial isolates from different plant tissues and geographical origins and then selected those with the strongest ability to reduce fire blight symptoms ex vivo and remarkable in vitro antagonistic activity against E.

First report of bacterial leaf blight caused by pv. on carrots in Spain.

In September 2019, symptoms resembling those of bacterial leaf blight were observed on carrot plants ( L. subsp. Hoffm.

Complete Circularized Genome Data of Two Spanish strains of (IVIA5235 and IVIA5901) Using Hybrid Assembly Approaches.

is an economically important plant pathogenic bacterium of global importance associated, since 2013, with a devastating epidemic in olive trees in Italy. Since then, several outbreaks of this pathogen have been reported in other European member countries including Spain, France, and Portugal. In Spain, the three major subspecies (subsp.

Emergence of a Plant Pathogen in Europe Associated with Multiple Intercontinental Introductions.

Pathogen introductions have led to numerous disease outbreaks in naive regions of the globe. The plant pathogen has been associated with various recent epidemics in Europe affecting agricultural crops, such as almond, grapevine, and olive, but also endemic species occurring in natural forest landscapes and ornamental plants. We compared whole-genome sequences of subspecies from America and strains associated with recent outbreaks in southern Europe to infer their likely origins and paths of introduction within and between the two continents.

Draft Genome Resources of Two Strains ("ESVL" and "IVIA5901") of Xylella fastidiosa Associated with Almond Leaf Scorch Disease in Alicante, Spain.

An outbreak of Xylella fastidiosa subsp. multiplex sequence type ST6 was discovered in 2017 in mainland Spain affecting almond trees. Two cultured almond strains, "ESVL" and "IVIA5901," were subjected to high throughput sequencing and the draft genomes assembled.

Draft Genome Sequence of Xylella fastidiosa subsp. Strain IVIA5235, Isolated from Prunus avium in Mallorca Island, Spain.

We report the complete annotated genome sequence of the plant-pathogenic bacterium Xylella fastidiosa subsp. strain IVIA5235. This strain was recovered from a cherry tree in Mallorca, Spain.

Xanthomonas prunicola sp. nov., a novel pathogen that affects nectarine (Prunus persica var. nectarina) trees.

Three isolates obtained from symptomatic nectarine trees (Prunus persica var. nectarina) cultivated in Murcia, Spain, which showed yellow and mucoid colonies similar to Xanthomonas arboricola pv. pruni, were negative after serological and real-time PCR analyses for this pathogen.

Genetic diversity reflects geographical origin of Ralstonia solanacearum strains isolated from plant and water sources in Spain.

The characterization and intraspecific diversity of a collection of 45 Ralstonia solanacearum strains isolated in Spain from different sources and geographical origins is reported. To test the influence of the site and the host on strain diversity, phenotypic and genotypic analysis were performed by a polyphasic approach. Biochemical and metabolic profiles were compared.

Lateral flow immunoassay for on-site detection of Xanthomonas arboricola pv. pruni in symptomatic field samples.

Xanthomonas arboricola pv. pruni is a quarantine pathogen and the causal agent of the bacterial spot disease of stone fruits and almond, a major threat to Prunus species. Rapid and specific detection methods are essential to improve disease management, and therefore a prototype of a lateral flow immunoassay (LFIA) was designed for the detection of X.

Transcriptional response of Erwinia amylovora to copper shock: in vivo role of the copA gene.

Fire blight is a devastating plant disease caused by the bacterium Erwinia amylovora, and its control is frequently based on the use of copper-based compounds whose mechanisms of action are not well known. Consequently, in this article, we investigate the response of E. amylovora to copper shock by a whole-genome microarray approach.

Medfly Ceratitis capitata as Potential Vector for Fire Blight Pathogen Erwinia amylovora: Survival and Transmission.

Monitoring the ability of bacterial plant pathogens to survive in insects is required for elucidating unknown aspects of their epidemiology and for designing appropriate control strategies. Erwinia amylovora is a plant pathogenic bacterium that causes fire blight, a devastating disease in apple and pear commercial orchards. Studies on fire blight spread by insects have mainly focused on pollinating agents, such as honeybees.

Role for Rhizobium rhizogenes K84 cell envelope polysaccharides in surface interactions.

Rhizobium rhizogenes strain K84 is a commercial biocontrol agent used worldwide to control crown gall disease. The organism binds tightly to polypropylene substrate and efficiently colonizes root surfaces as complex, multilayered biofilms. A genetic screen identified two mutants in which these surface interactions were affected.

Marinomonas alcarazii sp. nov., M. rhizomae sp. nov., M. foliarum sp. nov., M. posidonica sp. nov. and M. aquiplantarum sp. nov., isolated from the microbiota of the seagrass Posidonia oceanica.

Five novel Gram-reaction-negative aerobic marine bacterial strains with DNA G+C contents <50 mol% were isolated from the seagrass Posidonia oceanica. 16S rRNA sequence analysis indicated that they belonged to the genus Marinomonas. Major fatty acid compositions, comprising C₁₀:₀ 3-OH, C₁₆:₀, C₁₆:₁ω7c and C₁₈:₁ω7c, supported the affiliation of these strains to the genus Marinomonas.

Exopolysaccharides favor the survival of Erwinia amylovora under copper stress through different strategies.

Erwinia amylovora causes fire blight, a destructive disease of rosaceous plants very difficult to control. We demonstrated that copper, employed to control plant diseases, induces the "viable-but-nonculturable" (VBNC) state in E. amylovora.

Taxonomic study of Marinomonas strains isolated from the seagrass Posidonia oceanica, with descriptions of Marinomonas balearica sp. nov. and Marinomonas pollencensis sp. nov.

Novel aerobic, Gram-negative bacteria with DNA G+C contents below 50 mol% were isolated from the culturable microbiota associated with the Mediterranean seagrass Posidonia oceanica. 16S rRNA gene sequence analyses revealed that they belong to the genus Marinomonas. Strain IVIA-Po-186 is a strain of the species Marinomonas mediterranea, showing 99.

Are molecular tools solving the challenges posed by detection of plant pathogenic bacteria and viruses?

Plant pathogenic bacteria, phytoplasmas, viruses and viroids are difficult to control, and preventive measures are essential to minimize the losses they cause each year in different crops. In this context, rapid and accurate methods for detection and diagnosis of these plant pathogens are required to apply treatments, undertake agronomic measures or proceed with eradication practices, particularly for quarantine pathogens. In recent years, there has been an exponential increase in the number of protocols based on nucleic-acid tools being those based on PCR or RT-PCR now routinely applied worldwide.

Survival strategy of Erwinia amylovora against copper: induction of the viable-but-nonculturable state.

Copper compounds, widely used to control plant-pathogenic bacteria, have traditionally been employed against fire blight, caused by Erwinia amylovora. However, recent studies have shown that some phytopathogenic bacteria enter into the viable-but-nonculturable (VBNC) state in the presence of copper. To determine whether copper kills E.

Influence of aquatic microbiota on the survival in water of the human and eel pathogen Vibrio vulnificus serovar E.

The eel and human pathogen Vibrio vulnificus serovar E (biotype 2) is seldom isolated from natural waters, although it can survive in sterilized artificial seawater microcosms for years. The main objective of the present study was to investigate whether aquatic microbiota can limit its survival and recovery from water samples. A set of preliminary experiments of survival in microcosms containing natural seawater and water from eel farms showed that the persistence of this pathogen was mainly controlled by grazing, and secondarily by bacterial competition.