Abstract Wheat leaves infected with Puccinia triticina, the causal agent of wheat leaf rust, were collected from across Canada in 2014. From these leaves, 102 single-pustule isolates were recovered and tested for virulence on 16 standard differential wheat lines, with 28 unique virulence phenotypes found. The most common were TBDG (16.7%), TBBG (13.7%), MLPS and TNBG (both at 7.8%). Most isolates (95) originated from Manitoba and Saskatchewan, and the most common phenotypes found in this region were TBDG (17.9%), TBBG (14.7%), MLPS and TNBG (both at 8.4%). From Ontario, six virulence phenotypes were found from seven isolates: TCGJ (two isolates), MBDS, MCQG, MFPS, MGBS and TBGS (one isolate each). Frequencies of virulence in 2014 increased for Lr2a, Lr2c, Lr26 and Lr10 when compared with 2013, while there were decreases in virulence to Lr9, Lr24, Lr3ka, Lr30, Lr14a, Lr21 and LrCen. When 30 isolates, representing most of the unique virulence phenotypes, were tested on adult plants nearly all were virulent to the adult plant resistance genes Lr12, Lr13 and Lr37, most were avirulent to Lr35, and all were avirulent to Lr22a. When this subset of isolates was inoculated onto additional seedling differentials, most were virulent to Lr15 and Lr14b and avirulent to Lr25 and Lr29, and all isolates were avirulent to Lr19, Lr32 and Lr52. There were intermediate levels of virulence on Lr3bg, Lr20, Lr23 and Lr28.

中文翻译：

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2014年加拿大小麦叶锈病病原体小麦锈病的生理特化

摘要 2014 年从加拿大各地收集了感染小麦叶锈病病原体 Puccinia triticina 的小麦叶子。从这些叶子中，回收了 102 个单脓疱分离株，并测试了对 16 个标准差异小麦品系的毒力，具有 28 个独特的毒力发现的表型。最常见的是 TBDG (16.7%)、TBBG (13.7%)、MLPS 和 TNBG（均为 7.8%）。大多数分离株 (95) 源自曼尼托巴省和萨斯喀彻温省，在该地区发现的最常见表型是 TBDG (17.9%)、TBBG (14.7%)、MLPS 和 TNBG (均为 8.4%)。在安大略省，从七种分离株中发现了六种毒力表型：TCGJ（两种分离株）、MBDS、MCQG、MFPS、MGBS 和 TBGS（每种分离株）。与 2013 年相比，2014 年 Lr2a、Lr2c、Lr26 和 Lr10 的毒力频率增加，而 Lr9、Lr24、Lr3ka、Lr30、Lr14a、Lr21 和 LrCen。当代表大多数独特毒力表型的 30 个分离株在成年植物上进行测试时，几乎所有的菌株都对成年植物抗性基因 Lr12、Lr13 和 Lr37 有毒性，大多数对 Lr35 无毒，并且都对 Lr22a 无毒。当这部分分离株被接种到额外的幼苗分化株上时，大多数分离株对 Lr15 和 Lr14b 有毒，对 Lr25 和 Lr29 无毒，所有分离株对 Lr19、Lr32 和 Lr52 无毒。Lr3bg、Lr20、Lr23 和 Lr28 具有中等毒力水平。当这部分分离株被接种到额外的幼苗分化株上时，大多数分离株对 Lr15 和 Lr14b 有毒，对 Lr25 和 Lr29 无毒，所有分离株对 Lr19、Lr32 和 Lr52 无毒。Lr3bg、Lr20、Lr23 和 Lr28 具有中等毒力水平。当这部分分离株被接种到额外的幼苗分化株上时，大多数分离株对 Lr15 和 Lr14b 有毒，对 Lr25 和 Lr29 无毒，所有分离株对 Lr19、Lr32 和 Lr52 无毒。Lr3bg、Lr20、Lr23 和 Lr28 具有中等毒力水平。