Abstract

Wheat leaves infected with Puccinia triticina, the causal agent of wheat leaf rust, were collected annually throughout Canada from 2015 to 2019. There were 47, 75, 44, 38 and 54 different virulence phenotypes, respectively, found annually, representing 154 unique virulence phenotypes. From Alberta, there were three virulence phenotypes, MBDS, TDBJ, and TDBS, found in 2015 and eight in 2019, the most common being MBDS and TNBJ (both 20%). The most common virulence phenotypes found in Manitoba and Saskatchewan were MBDS (17.8%) and TNBG (16.3%) in 2015, MNPS (17.2%) and MBDS (15.9%) in 2016, MNPS (41.9%) and TBBG (17.2%) in 2017, MNPS (35.3%) and TBBG (34.8%) in 2018, and MNPS (54.7%) and MBDS (10.7%) in 2019. In Ontario, the most common virulence phenotypes found were MBTN (25%) and MBDS (16.7%) in 2015, MCQQ (13.6%) in 2016, MBTN (33.3%) and PBDG (19.0%) in 2017, TFPJ (13.6%) in 2018, and MCTN (14.5%) and MBTN (10.9%) in 2019. In Quebec the most common virulence phenotypes found were TBBG (66.7%) and MLDS (33.3%) in 2015, TCGJ (23.1%) and MBTN (15.4%) in 2017, MCQH (26.3%) and FCPT (21.1%) in 2018, and MBTN and MCRS (both 18.2%) in 2019. The frequencies of virulence varied on all resistance genes over these years. Within Canada, virulence on Lr21 peaked in 2018 at 39.9% and then declined in 2019, with a similar trend noticed for virulence on Lr2a and Lr2c. There was no virulence detected on Lr19, Lr29, Lr32, Lr52, and Lr22a, while virulence on Lr25 was rare.

摘要

小麦叶片感染小麦锈菌从 2015 年到 2019 年，加拿大每年都会收集小麦叶锈病的病原体 艾伯塔省 2015 年发现了三种毒力表型，MBDS、TDBJ 和 TDBS，2019 年发现了八种，最常见的是 MBDS 和 TNBJ（均为 20%）。在曼尼托巴省和萨斯喀彻温省发现的最常见的毒力表型是 2015 年的 MBDS（17.8%）和 TNBG（16.3%），2016 年的 MNPS（17.2%）和 MBDS（15.9%），MNPS（41.9%）和 TBBG（17.9%）。 2017 年，2018 年为 MNPS（35.3%）和 TBBG（34.8%），2019 年为 MNPS（54.7%）和 MBDS（10.7%）。在安大略省，发现的最常见的毒力表型是 MBTN（25%）和 MBDS（ 16.7%)，2015 年，MCQQ (13.6%)，2017 年 MBTN (33.3%) 和 PBDG (19.0%)，2018 年 TFPJ (13.6%)，和 MCTN (14.5%) 和 MBTN (10.9%)。在魁北克，2015 年发现的最常见毒力表型是 TBBG (66.7%) 和 MLDS (33.3%)，TCGJ (23.1%) 和 MBTN (15.4%) 2017 年，2018 年的 MCQH（26.3%）和 FCPT（21.1%），以及 2019 年的 MBTN 和 MCRS（均为 18.2%）。这些年来所有抗性基因的毒力频率各不相同。在加拿大，毒力Lr21在 2018 年达到 39.9% 的峰值，然后在 2019 年下降，对Lr2a和Lr2c 的毒力也有类似的趋势。在Lr19、Lr29、Lr32、Lr52和Lr22a上未检测到毒力，而对Lr25 的毒力很少见。