Cline, Erica T. & Amy Y. Rossman. Septoria malagutii sp. nov., cause of annular leaf spot of potato. Mycotaxon 98: 125 - 137. 2006.

ABSTRACT: The fungus causing annular leaf spot of potato, reported only from South America, poses a risk as a potentially invasive species due to its ability to flourish in the cooler temperatures typical of potato-producing regions in Europe and North America. Initially described as “Septoria lycopersici var. malagutii”, the variety is not validly published as required by the International Code of Botanical Nomenclature because no type specimen was specifically designated. Specimens of S. lycopersici var. lycopersici and S. lycopersici “var. malagutii” were examined and their rRNA ITS regions and (TEF)-1α genes were sequenced. The ‘var. malagutii’ conidia were significantly longer and narrower with the conidiogenous cells significantly shorter and narrower than the “var. lycopersici” cells. Although the sequenceswere similar — ITS at 99.6% and TEF-1α at 99.2% — the “var. lycopersici” ITS was more similar to several other Septoria species than to its “var. malagutii” counterpart, suggesting that the latter should recognized as a new species: Septoria malagutii.

KEYWORDS: plant pathogen, plant quarantine, systematics, translation elongation factor, internal transcribed spacer