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.

禾本科的全食病是由禾本科全麦酵母(Gaeumannomyces graminis )引起的。根据子囊孢子大小、丝足形态和寄主偏好， G. graminis被识别为四个变体。本研究的目的是通过结合基于 ITS、LSU、 tef1和rpb1部分基因序列的形态学和多位点系统发育分析，阐明全线酵母属物种和变种之间的界限。两个新属， Falciphoriella和Gaeumannomycella随后被引入Magnaporthaceae中。由此产生的系统发育揭示了全曼酵母属中以前被忽视的几种神秘物种。全线酵母属分离物分布在四个主要分支中，从中可以划分出 19 个物种，其中 12 个是科学上新的物种。我们的结果表明，以前的品种Gaeumannomyces graminis var.燕麦和全麦酵母变种。小麦代表了在系统发育上不同于G. graminis 的物种，为此引入了新的组合G. avenae和G. tritici 。根据分子数据、形态和寄主偏好， Gaeumannomyces graminis var. maydis被提议作为G. radicicola的同义词。此外，还提供了禾本科全脂酵母（Gaeumannomyces graminis var.）的表型。指定avenae是为了帮助稳定该名称的应用。