Relationships among Botryosphaeria species and associated anamorphic fungiinferred from the analyses of ITS and 5.8S rDNA sequences

摘要

Distance, parsimony and maximum likelihood analyses of sequence data from the internal transcribed spacers (ITS1 and ITS2) and 5.88 rDNA were used to infer the phylogenetic relationships among Botryosphaeria species and associated anamorphic fungi. The ingroup contained 52 isolates of 16 Botryoshaeria species and related taxa. A total of 6 outgroup species from putatively related families or orders were included in the analyses. Results indicate that the genus Botryosphaeria is not monophyletic, with B. vaccinii and Phyllosticta vaccinii not closely related to other fungi comprising this genus. The main group of Botryosphaeria species and related anamorphic fungi contains two distinct clades: one with light-colored and narrow conidia and the other with dark-colored and broader conidia. Two sections, Hyala and Brunnea, were proposed to represent these two groups. Botryosphaeria ribis and B. dothidea. are distinct. Diplodia pinea f. sp. cupressi is different from A and B RAPD marker groups of Sphaeropsis sapinea. Placement of a species within the form genera Sphaeropsis or Dipbodia does not necessarily indicate a very close relationship with other taxa within that same genus. The name B. stevensii may have been applied to more than one species. Isolates under different species names, such as those included in the cluster containing B. quercuum, might actually; be the same species. Our study indicates that the genus Botryosphaeria needs additional study and substantial taxonomic revision.