Multi-gene genealogies and morphological data support Diplodia cupressi sp nov., previously recognized as D-pinea f. sp cupressi, as a distinct species

The causal agent of Diplodia canker of cypress (Cupressus spp.) in the Mediterranean region was originally thought to represent a sub-population of the pine pathogen Diplodia pinea and was referred to as D. pinea f. sp. cupressi. In the USA a similar fungus causing canker and dieback of Juniperus spp. was referred to as Diplodia mutila (teleomorph: Botryosphaeria stevensii). The aim of this study was to characterise the cypress pathogen in terms of morphology and sequences of the ITS region, the β-tubulin and translation elongation factor 1-α genes. Phylogenetic analyses showed that the cypress canker pathogen resides in a clade together with other Diplodia species. It is, however, distinct from both D. pinea and D. mutila and more closely related to Botryosphaeria tsugae. The distinct phylogenetic position is supported by differences in conidial morphology and it is, therefore, described as Diplodia cupressi sp. nov.