The oak wilt pathogen, Ceratocystis fagacearum, may be another example of a damaging, exotic species in forest ecosystems in the United States. Though C. fagacearum has received much research attention, the origin of the fungus is unknown. The pathogen may have been endemic at a low incidence until increased disturbances, changes in land use, and forest management created conditions favorable for disease epidemics. The host genus Quercus contains some relatively resistant species native to the United States, further supporting the hypothesis that the pathogen is native in origin. However, there are also many common, highly susceptible Quercus species--a characteristic typical of introduced pathogens. Most convincingly, studies have shown that the known populations of C. fagacearum have experienced a severe genetic bottleneck that can only be explained by a single introduction. The weight of evidence indicates that C. fagacearum is an introduced pathogen, with possible origins in Central or South America, or Mexico.

中文翻译：

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橡树枯萎真菌Ceratocystis fagacearum的起源。

橡树枯萎病原菌Ceratocystis fagacearum，可能是美国森林生态系统中具有破坏性的外来物种的另一个例子。尽管C.fagacearum受到了很多研究关注，但真菌的来源尚不清楚。在增加干扰，土地利用变化和森林管理创造了有利于疾病流行的条件之前，病原体可能是低发病率的地方病。宿主栎属包含一些美国本土相对抗性的物种，进一步支持了该病原体是起源的假说。但是，也有许多常见的，高度易感的栎属物种，这是引入的病原体的典型特征。最有说服力的是，研究表明已知的C种群。fagacearum经历了严重的遗传瓶颈，只能通过一次介绍来解释。有力的证据表明，C。fagacearum是一种引入的病原体，可能起源于中美洲或南美洲或墨西哥。