Details

Autor(en) / Beteiligte

• Ferreira, Bruno W.
• Barreto, Robert W.

Titel

Debunking Acroconidiella

Ist Teil von

• Mycological progress, 2019-11, Vol.18 (11), p.1303-1315

Ort / Verlag

Berlin/Heidelberg: Springer Berlin Heidelberg

Erscheinungsjahr

2019

Link zum Volltext

Quelle

SpringerLink (Online service)

Beschreibungen/Notizen

• Acroconidiella was proposed to accommodate Acroconidiella tropaeoli , a fungal species causing leaf spots on Tropaeolum majus . At the time, it was recognized as deserving to be treated as a distinct genus because, although being somewhat similar to Alternaria , it did not present muriform conidia formed in chains. More recent observations of A. tropaeoli in culture forming acropetal conidial chains, and the recognition of several non-dictioconidial species as belonging to Alternaria , prompted a reappraisal of the genus, starting with the re-examination of the type species. Samples of Acroconidiella tropaeoli , and also of Acroconidiella trisepta , were recollected in Brazil, and a study involving an analysis of their morphology, under light microscopy and SEM, and a molecular phylogenenetic analysis was performed. A multi-gene phylogeny, including the large subunit of the nrDNA (nc LSU rDNA), internal transcribed spacer (ITS) region, translation elongation factor 1-α ( EF1 ), and polymerase II second largest subunit ( RPB2 ), placed A. tropaeoli within Alternaria , close to A. sonchi and A. cinerariae . The ITS and nc LSU rDNA phylogenetic study of A. trisepta placed it within Dendryphiella . The new combination Dendryphiella trisepta comb. nov is proposed to accommodate A. trisepta. Nevertheless, the new name Alternaria obtusa is proposed for Acroconidiella tropaeoli since it could not be recombined into Alternaria tropaeoli because this name is already in use for another valid (and distinct) species in this genus described from India. This study showed that Acroconidiella is an artificial genus which is now rejected, since its type species belongs to Alternaria —which has nomenclatural priority over Acroconidiella . Other species placed in Acroconidiella , given below, await reappraisal in order to determine their correct taxonomic affinity.