Morphophylogenetic analyses revealed that Podosphaera tridactyla constitutes a species complex

ABSTRACT

Podosphaera tridactyla (s. lat.) is a powdery mildew species occurring on a wide range of Prunus spp. almost worldwide. We have investigated the phylogeny of the Po. tridactyla complex, with special emphasis on potential aspects of cryptic speciation. The results suggested that Po. tridactyla represents a species complex consisting of at least 12 different species. Based on detailed morphological examinations and molecular sequence analyses, we propose dividing Po. tridactyla s. lat. into 10 species, encompassing 7 new species (Po. ampla, Po. pruni-avium, Po. pruni-cerasoidis, Po. prunigena, Po. pruni-lusitanicae, Po. prunina, and Po. pruni-japonicae) and 3 known species (Po. longiseta, Po. salatai, and Po. tridactyla s. str.). Oidium passerinii on Pr. laurocerasus is confirmed as a synonym of Po. tridactyla s. str. Epitypes are designated for Po. tridactyla and Oidium passerinii.

KEYWORDS:

• Erysiphales
• evolution
• molecular analyses
• powdery mildews
• ribosomal DNA
• 7 new taxa

ACKNOWLEDGMENTS

We are much obliged to the curator for fungal collections of GLM for allowing us to examine several powdery mildew collections deposited in this herbarium. The first author thanks Dr. Makoto Shinohara for his support in all aspects during the work.

Additional information

Funding

This work was financially supported in part by a Grant-in-Aid for Scientific Research (nos. 16K07613 and 16F16097) from the Japan Society for the Promotion of Science to Susumu Takamatsu and a Japan Society for the Promotion of Science postdoctoral fellowship (no. P16097) to Jamjan Meeboon.