Exploring fungal mega-diversity: Pseudocercospora from Brazil

Abstract

Although the genus Pseudocercospora has a worldwide distribution, it is especially diverse in tropical and subtropical countries. Species of this genus are associated with a wide range of plant species, including several economically relevant hosts. Preliminary studies of cercosporoid fungi from Brazil allocated most taxa to Cercospora, but with the progressive refinement of the taxonomy of cercosporoid fungi, many species were relocated to or described in Pseudocercospora. Initially, species identification relied mostly on morphological features, and thus no cultures were preserved for later phylogenetic comparisons. In this study, a total of 27 Pseudocercospora spp. were collected, cultured, and subjected to a multigene analysis. Four genomic regions (LSU, ITS, tef1 and actA) were amplified and sequenced. A multigene Bayesian analysis was performed on the combined ITS, actA and tef1 sequence alignment. Our results based on DNA phylogeny, integrated with ecology, morphology and cultural characteristics revealed a rich diversity of Pseudocercospora species in Brazil. Twelve taxa were newly described, namely P. aeschynomenicola, P. diplusodonii, P. emmotunicola, P. manihotii, P. perae, P. planaltinensis, P. pothomorphes, P. sennae-multijugae, P. solani-pseudocapsicicola, P. vassobiae, P. wulffiae and P. xylopiae. Additionally, eight epitype specimens were designated, three species newly reported, and several new host records linked to known Pseudocercospora spp.

Fungal Planet description sheets: 785– 867

“…Notes — Cercosporoid fungi include several genera of microfungi with cosmopolitan distribution and are highly diverse especially in tropical and subtropical countries (Crous et al 2013, Bakhshi et al 2014, Silva et al 2016). Pseudocercospora species can be found as saprobes, endophytes, hyperparasites, being very common as plant pathogens – causing mainly leaf spots (Crous et al 2013, Braun et al 2016, Guatimosim et al 2016).…”

Fungal Planet description sheets: 625–715

“…Notes — Pseudocercospora is the second largest genus of cercosporoid fungi containing fungi which were originally placed in Cercospora but have conidia which are generally pigmented and have hila which are unthickened and not darkened. They are often found causing leaf spots on a wide range of plant hosts, including several crop species of economic importance ( Crous et al 2013 , Bakhshi et al 2014 , Silva et al 2016 ). There are two species of Pseudocercospora described on Prunus persicae , namely Pseudocercospora pruni-persicicola and P. prunicola.…”

Fungal Planet description sheets: 558–624

“…Notes — Nineteen Pseudocercospora species have been described from hosts in the Melastomataceae : P. aciotidis , P. curta , P. dissotidis , P. erythrogena , P. leandrae , P. melastomobia , P. miconiae , P. miconiicola , P. miconiigena , P. mirandensis , P. monochaeticola , P. osbeckiae , P. oxysporae , P. sub-synnematosa , P. tamoneae , P. tibouchina-herbaceae , P. tibouchinae , P. tibouchinicola and P. tibouchinigena ( Parreira et al 2014 , Silva et al 2016 , Farr & Rossman 2017 ). However, only one species of Pseudocercospora is known to occur on a member of Leandra ( Crous & Braun 2003 , Farr & Rossman 2017 ), namely P. leandrae on Leandra subseriata from Colombia and Ecuador ( Crous & Braun 2003 ).…”