FVA Forest Research Institute of Baden-Württemberg (FVA-BW), Dept. Forest Protection, Wonnhaldestr. 4, D-79100 Freiburg, Germany.
WSL Swiss Federal Research Institute, Zürcherstrasse 111, CH-8903 Birmensdorf, Switzerland.
Fungal Biol. 2014 Feb;118(2):193-210. doi: 10.1016/j.funbio.2013.11.009. Epub 2013 Dec 1.
Chestnut blight in south-western Germany was first reported in 1992 and is since expanding in distribution. Here we investigated the invasion history of Cryphonectria parasitica and its associated hypovirus. For this, we characterized 284 isolates collected between 1992 and 2012 for hypovirulence, vegetative compatibility (vc), mating type, and microsatellite haplotype. A total of 27 haplotypes and 15 vc types were observed, although the C. parasitica population analyzed is currently dominated to 50 % by one haplotype and to 64 % by the vc type EU-2. Structure analysis indicated two divergent genetic pools. Over 66 % of the haplotypes belonged to a pool probably originating from northern Italy. Further diversification is expected due to ongoing sexual recombination, but also to new migration and additional introductions. Cryphonectria hypovirus 1 (CHV-1) was found in four of five C. parasitica populations from Baden-Württemberg. Genetic analysis of the 35 CHV-1 isolates obtained revealed that they all belong to the German subtype, although they have clearly diverged from the first German hypovirus isolated in 1992. Our study suggests that C. parasitica has been introduced into Germany several times from two different gene pools, whereas the hypovirus most probably has a single origin.
1992 年首次报道了德国西南部的栗疫病，此后其分布范围不断扩大。在这里，我们研究了栗疫病菌及其相关的拟病毒的入侵历史。为此，我们对 1992 年至 2012 年间收集的 284 个分离株进行了拟弱毒、营养体亲和性（vc）、交配型和微卫星单倍型特征分析。共观察到 27 个单倍型和 15 个 vc 类型，尽管分析的栗疫病菌种群目前主要由一个单倍型占 50%，由 vc 类型 EU-2 占 64%。结构分析表明存在两个分化的遗传群体。超过 66%的单倍型属于可能源自意大利北部的一个群体。由于持续的有性重组，以及新的迁移和额外的引入，预计会进一步多样化。在巴登-符腾堡州的五个栗疫病菌种群中的四个种群中发现了栗疫病菌拟病毒 1（CHV-1）。对获得的 35 个 CHV-1 分离株进行的遗传分析表明，它们都属于德国亚型，尽管它们与 1992 年首次从德国分离的第一个拟病毒明显分化。我们的研究表明，栗疫病菌已经从两个不同的基因库多次引入德国，而拟病毒很可能只有一个起源。
