Acknowledgements We are very grateful to Javier Diéguez-Uribeondo and Mark W. Vandersea for providing samples of closely related Aphanomyces strains. We thank Christian Holler, Gerhard Woschitz, Stefan Magg, Rudolf Lengauer, Hannes Hager and Reinhard Pekny for providing crayfish samples. Georg Mair, Joachim Spergser, BIBF 1120 concentration Gunther Vogl, Klaus Kotschy,

Claus Vogl, Renate Rosengarten, Fritz Pittner and Michael Hess are acknowledged for support. We are indebted to Steve Weiss for comments on the manuscript. This project was supported by the Austrian Federal Ministry of Agriculture, Forestry, Environment and Water Management (grant no. 1362 to EL). Role of the Sponsor The funding organisation had no role in the design and conduct of the study; collection, management, analysis, and interpretation of the data; and preparation, review, or approval of the manuscript. Electronic supplementary material Additional file 1: Species identification

of Austrian A. astaci strains Gb04, Z12, and GKS07 based on phylogenetic VX-680 ic50 analysis and constitutive chitinase activity in substrate-free medium. ITS sequence and chitinase expression in chitin-free medium are criteria to classify a strain as A. astaci (PDF 215 KB) Additional file 2: Sequences of 3′ untranslated regions (UTRs) of CHI2 and CHI3 mRNAs. Alignment shows differences between 3′ UTRs of CHI2 and CHI3 mRNAs (PDF 63 KB) Additional file 3: Amino-acid substitutions in the GH18 catalytic site of oomycete species. Table lists amino-acid substitutions in the GH18 catalytic site of oomycete species (PDF 55 KB) Additional file 4: O-linked glycosylation and phosphorylation predicted for Chi2 and Chi3. Predicted O-linked glycosylations learn more and phosporylations at serine and threonine residues for Chi2 and Chi3 are listed in a table Aldehyde dehydrogenase (PDF 100 KB) Additional file 5: Alignment of primer target sites for the 5.8S rRNA gene used as endogenous control in qPCR/MCA. Primers target conserved sites in the 5.8S rRNA gene of various oomycete species (PDF 192 KB) Additional file 6: A conventional PCR assay for detection of A. astaci that may fail to discriminate between closely related species. Alignment of primer sites for a conventional PCR

assay reported for detection of A. astaci (PDF 131 KB) Additional file 7: Design of a homologous IPC for use in the qPCR/MCA or qPCR assays. The IPC monitored by a characteristic melting temperature or by an alternatively labeled hydrolysis probe in the qPCR/MCA or qPCR assays, respectively, helps to prevent false-negative detection due to insufficient extraction and/or amplification. (PDF 117 KB) Additional file 8: TaqMan qPCR assay design for sensitive detection and quantification of A. astaci. Primers, but also TaqMan probe facilitate discrimination between A. astaci and various related or relevant oomycete species. (PDF 108 KB) References 1. Lamour KH, Win J, Kamoun S: Oomycete genomics: new insights and future directions. FEMS Microbiol Lett 2007,274(1):1–8.