Phylogeny and taxonomy of Cercospora malkoffii (Mycosphaerellaceae).

Abstract

The phylogeny and taxonomy of Cercospora malkoffii, an anamorphic ascomycete (Mycosphaerellaceae) causing a phytopathologically relevant leaf-spot disease on anise (Pimpinella anisum), are examined and clarified. This species is currently treated as belonging to the genus Passalora, based on a morphological species concept. However, genera of the Mycosphaerellaceae in general and particularly Passalora s. lat. underwent significant taxonomic changes in the past decades owing to comprehensive molecular phylogenetic revisions of cercosporoid fungi. Cercospora malkoffii has recently been repeatedly observed in commercial fields of P. anisum and has been isolated and cultivated in this study. Based on these cultures, ITS, LSU, CaM, tef1, tub2, and rpb2 sequences were retrieved and phylogenetic analyses were performed. These analyses revealed that C. malkoffii pertains to the genus Fusoidiella that currently comprises two former Passalora species on apiaceous hosts. Accordingly, the new combination Fusoidiella malkoffii is introduced. In addition, an epitype is designated here for C. malkoffii, and a pathogenicity test has been successfully carried out to fulfil Koch's postulates. Citation: Kreth L-S, Groenewald JZ, Braun U, Götz M (2025). Phylogeny and taxonomy of Cercospora malkoffii (Mycosphaerellaceae). Fungal Systematics and Evolution 16: 233-242. doi: 10.3114/fuse.2025.16.13.