Key Laboratory of Biodiversity and Biogeography, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, Yunnan, People's Republic of China.
PLoS One. 2012;7(5):e37567. doi: 10.1371/journal.pone.0037567. Epub 2012 May 18.
The wild gourmet mushroom Boletus edulis and its close allies are of significant ecological and economic importance. They are found throughout the Northern Hemisphere, but despite their ubiquity there are still many unresolved issues with regard to the taxonomy, systematics and biogeography of this group of mushrooms. Most phylogenetic studies of Boletus so far have characterized samples from North America and Europe and little information is available on samples from other areas, including the ecologically and geographically diverse regions of China. Here we analyzed DNA sequence variation in three gene markers from samples of these mushrooms from across China and compared our findings with those from other representative regions. Our results revealed fifteen novel phylogenetic species (about one-third of the known species) and a newly identified lineage represented by Boletus sp. HKAS71346 from tropical Asia. The phylogenetic analyses support eastern Asia as the center of diversity for the porcini sensu stricto clade. Within this clade, B. edulis is the only known holarctic species. The majority of the other phylogenetic species are geographically restricted in their distributions. Furthermore, molecular dating and geological evidence suggest that this group of mushrooms originated during the Eocene in eastern Asia, followed by dispersal to and subsequent speciation in other parts of Asia, Europe, and the Americas from the middle Miocene through the early Pliocene. In contrast to the ancient dispersal of porcini in the strict sense in the Northern Hemisphere, the occurrence of B. reticulatus and B. edulis sensu lato in the Southern Hemisphere was probably due to recent human-mediated introductions.
野生食用蘑菇牛肝菌及其近缘种具有重要的生态和经济意义。它们分布于整个北半球，但尽管它们无处不在，关于该蘑菇群的分类学、系统学和生物地理学仍存在许多悬而未决的问题。迄今为止，对牛肝菌的大多数系统发育研究都对来自北美的和欧洲的样本进行了特征描述，而来自其他地区的样本（包括生态和地理上多样化的中国地区）的信息很少。在这里，我们分析了来自中国各地的这些蘑菇样本的三个基因标记的 DNA 序列变异，并将我们的发现与其他代表性地区的发现进行了比较。我们的研究结果揭示了十五种新的系统发育种（约占已知种的三分之一）和一个新鉴定的谱系，由来自热带亚洲的 Boletus sp. HKAS71346 代表。系统发育分析支持东亚是 porcini 近缘种的多样性中心。在这个近缘种中，牛肝菌是唯一已知的全北极种。其他大多数系统发育种的分布范围都受到地理限制。此外，分子年代学和地质证据表明，该蘑菇群起源于始新世的东亚，随后从中新世到上新世早期通过扩散和随后的物种形成在亚洲、欧洲和美洲的其他地区进化。与北半球严格意义上的牛肝菌的古老扩散形成鲜明对比的是，南部半球的 B. reticulatus 和 B. edulis sensu lato 的出现可能是由于最近人类介导的引入。
