Spread of fire blight in Austria and Hungary - variability of Erwinia amylovora strains

Abstract

First outbreaks of fire blight were detected in Austria in 1993 and in Hungary in 1995. 137 Erwinia amylovora isolates were compared by PCR-RFLP, sequencing of the repeat region of the PstI fragment of plasmid pEA29, RAPD and AFLP analysis. Differences of repeat numbers in first isolates were observed. Six isolates showed different RAPD profiles. In AFLP analysis, so far, no differences in fragment pattern were determined. Pathogenicity tests with micropropagated apple cultivars revealed differences in plant susceptibility and in virulence of isolates. Responses of Malus tissue were visualized by the use of epifluorescence microscopy through the localization and the production of substances involved in cellular defence mechanisms (e.g. flavonoids, lignin) in various susceptible cultivars. The effect of bacterial strains differing in pathogenicity is shown by cellular peroxidase and flavonoid production.

Phenotypic and genetic diversity of Erwinia amylovora: the causal agent of fire blight

“…Although most of the profiles obtained a similarity above 0.9 (Nei-Li coefficient, UPGMA method), some of the profiles differed significantly from the others. The RAPD technique also revealed the high homogeneity of E. amylovora isolates from other geographical regions (Keck et al 2002;Manulis et al 1998;Taylor and Hale 1998).…”

“…The use of AFLP led to the conclusion that the occurrence of fire blight in the provinces of Modena and Ferrara, was caused by a single introduction of E. amylovora (Minardi et al 2000). Similar analysis of Austrian and Hungarian isolates of this bacterium did not show any differences between the isolates (Keck et al 2002). In Spain, an attempt was made to differentiate isolates of E. amylovora from different countries, using the rep-PCR (ERIC, BOX, IS50, and M13 primer) and the AFLP technique.…”

“…and from Pomoidae Gürtler and Stanisich (1996), Jeng et al (1999), McManus and Jones (1995b), Momol et al (1999) Slight differentiation of isolates from fruit trees Garbeva et al (1997) RFLP of genomic DNA ? PFGE Distinction of different types among European isolates and presentation of hypothetical ways of spreading of the pathogen Jock et al (2002), Ivanović et al (2010), Zhang and Geider (1997), Zhang et al (1998) Diversity among isolates from North America Jock et al (2002) Housekeeping genes High homogeneity among isolates tested Brennan et al (2002), Keck et al (2002), Manulis et al (1998), Puławska et al (2006), Taylor and Hale (1998) AFLP Lack of differences between isolates from Italy, Austria and Hungary Keck et al (2002), Minardi et al (2000) Differentiation of isolates according to geographic origin in Spain Donat et al (2007), Rico et al (2004) MLVA High diversity revealed among isolates tested Dreo et al (2010) CRISPR High diversity revealed among isolates tested Rezzonico et al (2011) Trees (2012) 26:3-12 9…”

Caracterización fenotípica y genotípica de aislados españoles de Erwinia amylovora.

“…Esta técnica se aplicó a una amplia colección de cepas de E. amylovora de Austria y Hungría, pero no se hallaron diferencias en los patrones obtenidos (Keck et al, 2002). Más recientemente, también se ha analizado una colección más reducida de cepas de este patógeno de diversos países, entre ellos España, obteniéndose perfiles distintos para casi todas ellas, aunque tampoco ha sido posible establecer relaciones con el hospedador ni con el año o el país de aislamiento (Rico et al, 2004).…”

“…, personal communication, 2004 Zwet, 1993Zwet, , 1996. More recently, in the present decade, E. amylovora has been detected in Ukraine and Slovakia (van der Zwet, 2002, personal communication, 2004).Since the detection of E. amylovora in southern France in 1978(Paulin & Lachaud, 1978, Spain was actively working to prevent the introduction of fire blight and was considered a protected country in relation to fire blight according to the EU legislation Table 1.Several studies have described the characterization of E. amylovora strains from some European countries, either phenotypically Paulin & Samson, 1973;Vantomme et al, 1982Vantomme et al, , 1986Mergaert et al, 1984) or genotypically (Momol et al, 1997;Zhang & Geider, 1997;Keck et al, 2002), but only two reports have described the recent occurrence of the fire blight pathogen in Spain (López et al, 1999a(López et al, , 2002a. The present study describes, for the first time, the characterization of a …”