ABSTRACT Rust disease was observed on populations of Suaeda californica near Morro Bay, California. The pathogen was identified as a species of Uromyces based on teliospore and urediniospore morphology and nuc 28S rDNA sequence analysis. The isolate was compared with previously described species of Uromyces that infect members of Chenopodiaceae, prompting a taxonomic reevaluation of Uromyces species on Suaeda. Herein, Uromyces rebeccae is described. It can be differentiated from the closely related U. chenopodii (syn.: Aecidium chenopodii-fruticosi; U. giganteus) based on host range, teliospore morphology, and 28S sequence data. The new combination, Uromyces chenopodii-fruticosi, is made for Aecidium chenopodii-fruticosi, the oldest name for Eurasian Suaeda rust. Finally, it was determined that U. giganteus likely does not occur in the United States and that the rust of S. taxifolia in the United States likely comprises a third, yet unnamed taxon, different from both U. rebeccae and U. chenopodii-fruticosi. This is the first record of a rust fungus on S. californica. An identification key for Uromyces species reported on Chenopodiaceae is provided.

中文翻译：

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Uromyces rebeccae，sp。11 月，在联邦濒危植物 California sea-blite (Suaeda californica) 上新描述的锈病

摘要 在加利福尼亚州莫罗湾附近的 Suaeda californica 种群中观察到锈病。根据冬孢子和乌氏孢子的形态学和 nuc 28S rDNA 序列分析，病原体被鉴定为一种 Uromyces。该分离物与先前描述的感染藜科成员的 Uromyces 物种进行了比较，促使对 Suaeda 上的 Uromyces 物种进行分类学重新评估。在此，描述了 Uromyces rebeccae。根据寄主范围、冬孢子形态和 28S 序列数据，它可以与密切相关的 U. chenopodii (syn.: Aecidium chenopodii-fruticosi; U. giganteus) 区分开来。新组合 Uromyces chenopodii-fruticosi 是为 Aecidium chenopodii-fruticosi 制作的，这是欧亚铁锈病的最古老名称。最后确定U. giganteus 可能不会发生在美国，并且美国的 S.taxfolia 锈病可能包括第三个但未命名的分类群，不同于 U. rebeccae 和 U. chenopodii-fruticosi。这是 S. californica 锈菌的第一个记录。提供了藜科上报道的 Uromyces 物种的识别密钥。