title: Take-all or nothing.
abstract: Take-all disease of Poaceae is caused by Gaeumannomyces graminis (Magnaporthaceae). Four varieties are recognised in G. graminis based on ascospore size, hyphopodial morphology and host preference. The aim of the present study was to clarify boundaries among species and varieties in Gaeumannomyces by combining morphology and multi-locus phylogenetic analyses based on partial gene sequences of ITS, LSU, tef1 and rpb1. Two new genera, Falciphoriella and Gaeumannomycella were subsequently introduced in Magnaporthaceae. The resulting phylogeny revealed several cryptic species previously overlooked within Gaeumannomyces. Isolates of Gaeumannomyces were distributed in four main clades, from which 19 species could be delimited, 12 of which were new to science. Our results show that the former varieties Gaeumannomyces graminis var. avenae and Gaeumannomyces graminis var. tritici represent species phylogenetically distinct from G. graminis, for which the new combinations G. avenae and G. tritici are introduced. Based on molecular data, morphology and host preferences, Gaeumannomyces graminis var. maydis is proposed as a synonym of G. radicicola. Furthermore, an epitype for Gaeumannomyces graminis var. avenae was designated to help stabilise the application of that name.
authors: CBS-KNAW Fungal Biodiversity Centre, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0002, South Africa.
authors: M
authors: M
authors: Hernández-Restrepo
authors: CBS-KNAW Fungal Biodiversity Centre, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands.
authors: J Z
authors: JZ
authors: Groenewald
authors: University of Florida - IFAS, Fort Lauderdale Research and Education Center, 3205 College Avenue, Fort Lauderdale (Davie), FL 33314, USA.
authors: M L
authors: ML
authors: Elliott
authors: Department of Plant Biology and Crop Science, Rothamsted Research, Harpenden, Herts AL5 2JQ, UK.
authors: G
authors: G
authors: Canning
authors: Department of Plant Biology and Crop Science, Rothamsted Research, Harpenden, Herts AL5 2JQ, UK.
authors: V E
authors: VE
authors: McMillan
authors: CBS-KNAW Fungal Biodiversity Centre, Uppsalalaan 8, 3584 CT Utrecht, The Netherlands; Department of Microbiology and Plant Pathology, Forestry and Agricultural Biotechnology Institute (FABI), University of Pretoria, Pretoria 0002, South Africa; Microbiology, Department of Biology, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands; Wageningen University and Research Centre (WUR), Laboratory of Phytopathology, Droevendaalsesteeg 1, 6708 PB Wageningen, The Netherlands.
authors: P W
authors: PW
authors: Crous
keywords: Cryptic species; Falciphoriella M. Hern.-Restr. & Crous; Falciphoriellasolaniterrestris M. Hern.-Restr. & Crous; G. australiensis M. Hern.-Restr. & Crous; G. californicus M. Hern.-Restr. & Crous; G. ellisiorum M. Hern.-Restr. & Crous; G. floridanus M. Hern.-Restr. & Crous; G. fusiformis M. Hern.-Restr. & Crous; G. glycinicola M. Hern.-Restr., G. Canning & Crous; G. graminicola M. Hern.-Restr. & Crous; G. hyphopodioides M. Hern.-Restr. & Crous; G. oryzicola M. Hern.-Restr. & Crous; G. setariicola M. Hern.-Restr. & Crous; G. walkeri M. Hern.-Restr. & Crous; Gaeumannomycella M. Hern.-Restr. & Crous; Gaeumannomycellacaricis M. Hern.-Restr. & Crous; Gaeumannomyces avenae (E. M. Turner) M. Hern.-Restr. & Crous; Gaeumannomyces graminis; Gaeumannomyces graminis var. avenae (E. M. Turner) Dennis; Gaeumannomyces tritici (J. Walker) M. Hern.-Restr. & Crous; Gaeumannomycesarxii M. Hern.-Restr. & Crous; Magnaporthaceae; Phylogeny; Triticum