A BSTRACT Since the early 2000s, reports on declining hornbeam trees (Carpinus betulus) are spreading in Europe. Two fungi are involved in the decline phenomenon: One is Anthostoma decipiens, but the other etiological agent has not been identified yet. We examined the morphology, phylogenetic position, and pathogenicity of yellow fungal isolates obtained from hornbeam trees from Austria, Georgia and Switzerland, and compared data with disease reports from northern Italy documented since the early 2000s. Results demonstrate distinctive morphology and monophyletic status of Cryphonectria carpinicola sp. nov. as etiological agent of the European hornbeam decline. Interestingly, the genus Cryphonectria splits into two major clades. One includes Cry. carpinicola together with Cry. radicalis, Cry. decipiens and Cry. naterciae from Europe, while the other comprises species known from Asia—suggesting that the genus Cryphonectria has developed at two evolutionary centres, one in Europe and Asia Minor, the other in East Asia. Pathogenicity studies confirm that Car. betulus is a major host species of Cry. carpinicola. This clearly distinguished Cry. carpinicola from other Cryphonectria species, which mainly occur on Castanea and Quercus.

中文翻译：

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Cryphonectria carpinicola sp. 十一月 与欧洲角树衰退有关

摘要自 2000 年代初以来，关于角树（Carpinus betulus）衰退的报道在欧洲传播开来。衰退现象涉及两种真菌：一种是Anhostoma decipiens，但另一种病原体尚未确定。我们检查了从奥地利、乔治亚州和瑞士的角树树中获得的黄色真菌分离株的形态、系统发育位置和致病性，并将数据与自 2000 年代初以来记录的意大利北部的疾病报告进行了比较。结果表明 Cryphonectria carpinicola sp. 的独特形态和单系状态。十一月 作为欧洲角树衰退的病原体。有趣的是，Cryphonectria 属分为两个主要分支。一个包括Cry。carpinicola 和 Cry 一起。激进分子，哭泣。decipiens 和 Cry。来自欧洲的naterciae，而另一种则包括在亚洲已知的物种——这表明 Cryphonectria 属已经在两个进化中心发展起来，一个在欧洲和小亚细亚，另一个在东亚。致病性研究证实，汽车。betulus 是 Cry 的主要宿主物种。卡皮尼科拉。这清楚地区分了Cry。carpinicola 来自其他 Cryphonectria 物种，主要发生在栗树和栎属上。