The genus
- PAR ID:
- 10373289
- Publisher / Repository:
- Wiley-Blackwell
- Date Published:
- Journal Name:
- New Phytologist
- Volume:
- 226
- Issue:
- 4
- ISSN:
- 0028-646X
- Page Range / eLocation ID:
- p. 987-1011
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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ABSTRACT Erysiphe species infecting oaks in North America are common and widespread, but compared to Asia and Europe, the taxonomy and phylogeny of North American species is unknown. The present study addresses this dispairity. Comprehensive multilocus phylogenetic analyses, includingCAM ,GAPDH ,GS , ITS,RPB2 andTUB , revealed a high degree of co‐evolution between North American oaks and theErysiphe spp. that infect them. A concatenated multilocus tree and individual trees based on single loci revealed many highly supported species clades. The clades are formally named to conform with the current taxonomic classification. Available names, such asE. abbreviata E. calocladophora andE. extensa , are associated with corresponding clades, and are newly circumscribed supported by ex‐type sequences or, if not available, by the designation of epitypes with ex‐epitype sequences.Erysiphe densissima is reintroduced for a clade that corresponds to the old name ‘E. extensa var.curta’ . Eight new species are described, includingErysiphe carolinensis ,E. gambelii ,E. occidentalis E. phellos ,E. pseudoextensa ,E. quercophila, andE. quercus ‐laurifoliaeE. schweinitziana . A new diagnostically and taxonomically relevant trait associated with the anamorphs of North AmericanErysiphe species on oaks has been assssed. This is a special conidiophore‐like lateral outgrowth of the superficial hyphae, comparable to ‘aerial hyphae,’ which are also known for species of the powdery mildew genusCystotheca which also infectQuercus species. -
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Summary The tree of life is highly reticulate, with the history of population divergence emerging from populations of gene phylogenies that reflect histories of introgression, lineage sorting and divergence. In this study, we investigate global patterns of oak diversity and test the hypothesis that there are regions of the oak genome that are broadly informative about phylogeny.
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