title: Ecological and physical barriers shape genetic structure of the Alpine porcini (Boletus reticuloceps).
abstract: The Alpine porcini, Boletus reticuloceps, is an ectomycorrhizal mushroom distributed in subalpine areas of Southwest China, central China, and Taiwan Island. This distribution pattern makes it an ideal organism to infer how ectomycorrhizal fungi have reacted to historical tectonic and climatic changes, and to illustrate the mechanism for the disjunction of organisms between Southwest China and Taiwan. In this study, we explored the phylogeographic pattern of B. reticuloceps by microsatellite genotyping, DNA sequencing, ecological factor analysis, and species distribution modeling. Three genetic groups from the East Himalayas (EH), northern Hengduan Mountains (NHM), and southern Hengduan Mountains (SHM), were identified. The earlier divergent SHM group is found under Abies in moister environments, whereas the EH and NHM groups, which are physically separated by the Mekong-Salween Divide, are found mainly under Picea in drier environments. Samples from Taiwan showed a close relationship with the SHM group. High mountains did not form dispersal barriers among populations in each of the EH, NHM, and SHM groups, probably due to the relatively weak host specificity of B. reticuloceps. Our study indicated that ecological heterogeneity could have contributed to the divergence between the SHM and the NHM-EH groups, while physical barriers could have led to the divergence of the NHM and the EH groups. Dispersal into Taiwan via Central China during the Quaternary glaciations is likely to have shaped its disjunct distribution.
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China.
authors.forename: Bang
authors.initials: B
authors.lastname: Feng
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Jian Wei
authors.initials: JW
authors.lastname: Liu
authors.affiliation: Department of Biology, McMaster University, Hamilton, ON , L8S 4K1, Canada.
authors.forename: Jianping
authors.initials: J
authors.lastname: Xu
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China.|University of Chinese Academy of Sciences, Beijing, 100049, China.
authors.forename: Kuan
authors.initials: K
authors.lastname: Zhao
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China.
authors.forename: Zai Wei
authors.initials: ZW
authors.lastname: Ge
authors.affiliation: Key Laboratory for Plant Diversity and Biogeography of East Asia, Kunming Institute of Botany, Chinese Academy of Sciences, Kunming, 650201, Yunnan, China. fungi@mail.kib.ac.cn.
authors.forename: Zhu L
authors.initials: ZL
authors.lastname: Yang
mesh_terms: D004271:DNA, Fungal / Q000032:analysis; D017753:Ecosystem; D019143:Evolution, Molecular; D014644:Genetic Variation; D005838:Genotype; D060005:Genotyping Techniques / Q000379:methods*; D018895:Microsatellite Repeats; D038821:Mycorrhizae / Q000145:classification* / Q000235:genetics; D010802:Phylogeny; D058974:Phylogeography; D017422:Sequence Analysis, DNA / Q000379:methods*
chemical_list: D004271:DNA, Fungal
keywords: Climatic heterogeneity; Disjunction; Dispersal; Host preference; Phylogeography; Physical isolation