title: Genetic variation within Podosphaera tridactyla reveals a paraphyletic species complex with biological specialization towards specific Prunus subgenera.
abstract: Podosphaera tridactyla (Ascomycota: Erysiphales) is a morphologically variable species occurring on Prunus s. lat. In order to assess the genetic variation within this species, the rDNA ITS region was amplified from 29 specimens from a range of Prunus species collected in Australia, Switzerland, and Korea. RFLP analysis of the PCR products revealed six groups, and a comparison of sequences from representatives of these groups revealed three clades: Clade I contained all specimens from Prunus subgen. Prunus; Clade 2 specimens from a variety of Prunus subgenera, except subgen. Prunus, and Podosphaera longiseta was closely allied to this clade; and Clade 3 contained two specimens, from Japan and Korea. Phylogenetic analysis comparing P. tridactyla with of a range of Podosphaera species suggests that P. tridactyla is paraphyletic.
authors.affiliation: Department of Primary Industries, Knoxfield Centre, Private Bag 15, Ferntree Gully Delivery Centre, Victoria 3156, Australia. james.cunnington@dpi.vic.gov.au
authors.forename: James H
authors.initials: JH
authors.lastname: Cunnington
authors.forename: Ann C
authors.initials: AC
authors.lastname: Lawrie
authors.forename: Ian G
authors.initials: IG
authors.lastname: Pascoe
mesh_terms: D001203:Ascomycota / Q000145:classification* / Q000235:genetics; D021903:DNA, Ribosomal Spacer / Q000032:analysis* / Q000235:genetics; D014644:Genetic Variation; D010802:Phylogeny; D012150:Polymorphism, Restriction Fragment Length; D027861:Prunus / Q000382:microbiology*
chemical_list: D021903:DNA, Ribosomal Spacer