Mycosphaerellaceae: Chaos or clarity?

Abstract

The Mycosphaerellaceae represent thousands of fungal species that are associated with diseases on a wide range of plant hosts. Understanding and stabilising the taxonomy of genera and species of Mycosphaerellaceae is therefore of the utmost importance given their impact on agriculture, horticulture and forestry. Based on previous molecular studies, several phylogenetic and morphologically distinct genera within the Mycosphaerellaceae have been delimited. In this study a multigene phylogenetic analysis (LSU, ITS and rpb2) was performed based on 415 isolates representing 297 taxa and incorporating ex-type strains where available. The main aim of this study was to resolve the phylogenetic relationships among the genera currently recognised within the family, and to clarify the position of the cercosporoid fungi among them. Based on these results many well-known genera are shown to be paraphyletic, with several synapomorphic characters that have evolved more than once within the family. As a consequence, several old generic names including Cercosporidium, Fulvia, Mycovellosiella, Phaeoramularia and Raghnildiana are resurrected, and 32 additional genera are described as new. Based on phylogenetic data 120 genera are now accepted within the family, but many currently accepted cercosporoid genera still remain unresolved pending fresh collections and DNA data. The present study provides a phylogenetic framework for future taxonomic work within the Mycosphaerellaceae.

Analysis of fungal endophytes in Scottish Sitka spruce plantations shows extensive infections, novel host partners and gives insights into origins

“…This is in agreement with Winton, Stone, Hansen, and Shoemaker (2007) and Videira et al (2017) showing that N. gaeumannii is in fact a member of the Mycosphaerellaceae, a family that is known to be to be polyphyletic (Crous, Braun, & Groenewald, 2007;Videira et al, 2017). gaeumannii also contains Pallidocercospora species and Neopseudocercosporella brassicola, other known species of family Mycosphaerellaceae (Capnodiales).…”

An evolutionary framework for host shifts – jumping ships for survival

“…Host jumps are usually detected by a lack of congruence between pathogen and host phylogeny; (Roy, ; Staats et al ., ; Choi & Thines, ), that is, the branching patterns in the phylogenetic trees of hosts and pathogens are different and do not mirror the relationships in the other group. While initially it was thought that pathogens and their hosts co‐evolve over longer time scales, and some early molecular phylogenies seemed to support this view (Whitfield, ; Begerow et al ., ), there has been an increasing amount of evidence that host jumps are a very common phenomenon, both in facultative (Staats et al ., ; Videira et al ., ) and obligate biotrophic pathogens (Roy, ; Refrégier et al ., ; Choi & Thines, ; Escudero, ; McTaggart et al ., ).…”

“…, there has been an increasing amount of evidence that host jumps are a very common phenomenon, both in facultative (Staats et al, 2005;Videira et al, 2017) and obligate biotrophic pathogens (Roy, 2001;Refr egier et al, 2008;Escudero, 2015;McTaggart et al, 2016).…”

Collapsimycopappus: A new leaf pathogen with mycopappus‐like propagules in Mycosphaerellaceae

“…Recent molecular studies on Mycosphaerellaceae have promoted the taxonomic revision of major pathogenic groups, such as Cercospora , Septoria and Ramularia ‐complex (e.g., Crous et al., ; Marin‐Felix et al., ; Quaedvlieg, Groenewald, de Jesús Yáñez‐Morales, & Crous, ; Quaedvlieg et al., , ; Verkley, Quaedvlieg, Shin, & Crous, ; Videira, Groenewald, Braun, Shin, & Crous, ; Videira et al., ). Although the present study revealed an unexpected lineage within Mycosphaerellaceae, we could not further resolve the circumscription of the family.…”

“…Collapsimycopappus is similar to Polythrincium in having sporodochial conidiomata and melanized conidia (Simon, Groenewald, & Crous, 2009), but differs in its lack of sympodially growing conidiophores with a spiral appearance. In addition, no genera with mycopappuslike propagules have been reported in Mycosphaerellaceae (Videira et al, 2017). Therefore, Collapsimycopappus is introduced as a new genus in Mycosphaerellaceae.…”