WSL Swiss Federal Research Institute, Birmensdorf, Switzerland.
Phytopathology. 2012 Jan;102(1):73-82. doi: 10.1094/PHYTO-02-11-0055.
Cryphonectria parasitica is the best-known example of an invasive forest pathogen in Europe. In southern Switzerland, chestnut blight was first reported in 1948 whereas, north of the Alps, it did not appear until the 1980s. Between 1995 and 2008, we sampled 640 C. parasitica isolates from nine populations south of the Alps and nine north of the Alps. Twelve historical isolates, collected between 1950 and 1972 in the south, were obtained from our collection. All 652 isolates were screened at 10 microsatellite loci to test for the existence of divergent genetic pools and to infer possible origins of haplotypes. In total, 52 haplotypes were identified. Structure software analysis indicated that 43 haplotypes (including all historical haplotypes) belonged to a main cluster, 6 haplotypes belonged to a different cluster, and 3 haplotypes had an intermediate allele pattern. All newly founded populations in northern Switzerland were initiated by one or just a few haplotypes from the main cluster, which probably came directly from the populations south of the Alps. Subsequently, genetic diversity increased through mutations, sexual reproduction, or new migrations. The highest increase in diversity was observed in populations where haplotypes from different genetic pools were encountered.
栓疫菌是欧洲最著名的入侵性森林病原体。在瑞士南部，栗疫病于 1948 年首次报道，而在阿尔卑斯山以北，直到 20 世纪 80 年代才出现。1995 年至 2008 年间，我们从阿尔卑斯山以南的九个种群和阿尔卑斯山以北的九个种群中采集了 640 个 Cryphonectria parasitica 分离株。我们的收藏中还获得了 12 个历史分离株，这些分离株是在 1950 年至 1972 年间在南部采集的。对所有 652 个分离株进行了 10 个微卫星基因座的筛选，以检测是否存在不同的遗传群体，并推断可能的单倍型起源。共鉴定出 52 个单倍型。结构软件分析表明，43 个单倍型（包括所有历史单倍型）属于一个主要群体，6 个单倍型属于一个不同的群体，3 个单倍型具有中间等位基因模式。瑞士北部的所有新成立的种群都是由来自主要群体的一个或几个单倍型引发的，这些单倍型可能直接来自阿尔卑斯山以南的种群。随后，通过突变、有性繁殖或新的迁移增加了遗传多样性。在遇到来自不同遗传群体的单倍型的种群中，多样性的增加幅度最大。
