Characterisation of Pseudomonas syringae Strains Associated with a Leaf Disease of Leek in Australia

Abstract

A necrotic leaf disease of leek (Allium ampeloprasum Porrum Group) is reported in Australia for the first time. The fluorescent pseudomonad consistently associated with diseased tissue was identified as Pseudomonas syringae by LOPAT tests (+,),),),+), carbon utilisation, bean and lemon inoculations and fatty acid methyl ester analysis. It was confirmed as P. syringae pv. porri by pathogenicity to leeks, bulb onions, spring onions, shallots and garlic, and by genetic analysis using 16S rDNA PCR, REP, ERIC and BOX PCR, and IS50 PCR. Comparison with reference strains of pv. porri from other countries showed similarity to known strains of pv. porri. The Australian leek strains were generally uniform in their biochemical reactions although three strains tested varied in their pathogenicity to other Allium spp. and varied from published data. All Australian strains shared the same genetic profile with strains from New Zealand, France and California. However, Japanese strains from leek and onion were distinct from the Australian strains and those from New Zealand, France and California. Data strongly support the hypothesis that the pathogen is seed-borne.

Preparing for the KIL: Receptor Analysis of Pseudomonas syringae pv. porri Phages and Their Impact on Bacterial Virulence

“…The main plant host is leek (Allium porrum), but also other members of the Allium family such as onions (Allium cepa) and shallots (Allium cepa var. aggregatum) can be infected [12]. In Belgium, we recently reported an increase in Pspo prevalence in leek plants [10].…”

“…Since then, it has become widespread and has been reported in Europe, Oceania, North America, and Asia [10]. Pspo typically causes leaf curling and leaf lesions in young leek plants while older plants develop water-soaked spots [11,12]. The main plant host is leek (Allium porrum), but also other members of the Allium family such as onions (Allium cepa) and shallots (Allium cepa var.…”

Characterization of Novel Bacteriophages for Biocontrol of Bacterial Blight in Leek Caused by Pseudomonas syringae pv. porri

“…Leek ( Allium porrum ) is the major host, but the pathogen has also been diagnosed on onion ( Allium cepa ) and shallot ( Allium cepa var. aggregatum ; Noble et al, 2006 ). The disease is known to be transmitted by seed (Koike et al, 1999 ; Ikene et al, 2003 ), but crop waste also plays a role in contaminating new leek plants in the field (van Overbeek et al, 2010 ).…”

“…Currently, the disease has spread globally and is reported in The Netherlands (Janse, 1982 ; van Overbeek et al, 2010 ), Italy (Varvaro, 1983 ), the United States (Koike et al, 1999 ), Australia (Noble et al, 2006 ), Greece (Glynos and Alivizatos, 2006 ), Japan (Goto, 1972 ), and Korea (Myung et al, 2011 , 2012 ). Typical symptoms include leaf curling and yellowing of the middle vein in young plants and water soaked spots on older leaves and flowering stems (Samson et al, 1998 ; Noble et al, 2006 ). Leek ( Allium porrum ) is the major host, but the pathogen has also been diagnosed on onion ( Allium cepa ) and shallot ( Allium cepa var.…”

Genetic diversity among Brenneria nigrifluens strains in Iran

“…These IS elements have been used as DNA markers to study the genetic variation, genomic rearrangement and genome plasticity of bacteria (Mahillon and Chandler 1998). IS50 from the transposon Tn5 has been used as primer for the assessment of genetic diversity in several bacterial genera including Pseudomonads (Weingart and Volksch 1997;Noble et al 2006).…”