Multiple <I>Didymella</I> teleomorphs are linked to the <I>Phoma clematidina</I> morphotype

Abstract

The fungal pathogen Phoma clematidina is used as a biological agent to control the invasive plant species Clematis vitalba in New Zealand. Research conducted on P. clematidina as a potential biocontrol agent against C. vitalba, led to the discovery of two perithecial-forming strains. To assess the diversity of P. clematidina and to clarify the teleomorph-anamorph relationship, phylogenetic analyses of 18 P. clematidina strains, reference strains representing the Phoma sections in the Didymellaceae and strains of related species associated with Clematis were conducted. Partial sequences of the ITS1, ITS2 and 5.8S rRNA gene, the ß-tubulin gene and 28S rRNA gene were used to clarify intra- and inter-species relationships. These analyses revealed that P. clematidina resolves into three well-supported clades which appear to be linked to differences in host specificity. Based on these findings, Didymella clematidis is newly described and the descriptions of P. clematidina and D. vitalbina are amended.

First report of Phoma clematidina the cause of leaf spot-wilt disease of Clematis pubescens in Australia

“…3b). Both cultural and morphological characteristics of the fungal isolates were similar to those described for P. clematidina (Boerema et al 2004;Woudenberg et al 2009). …”

Taxonomic circumscription and phylogenetics of novel didymellaceous taxa with brown muriform spores

“…Newly generated sequences from two Microsphaeropsis isolates (MFLU 16-0100 and MFLU 16-0097) grouped with isolates currently circumscribed as Microsphaeropsis olivacea and M. proteae (de Gruyter et al 2009, Aveskamp et al 2010, Crous et al 2011, Verkley et al 2014, Chen et al 2015. These taxa formed an isolated clade (Clade A , Fig 1) within Didymellaceae, but poorly supported in multi-gene analyses (69% in ML, <60 % in MP and <0.95 in BI).…”

Taxonomy and phylogeny of Laburnicola gen. nov. and Paramassariosphaeria gen. nov. (Didymosphaeriaceae, Massarineae, Pleosporales)

“…The ITS gene was amplified using the primers ITS5 and ITS4 (White et al 1990), the LSU region was amplified using the primer pair LROR and LR5 (Vilgalys and Hester 1990), SSU was amplified using the primers NS1 and NS4 (White et al 1990) and the tub2 region with the primers Btub2Fd and Btub4Rd (Woudenberg et al 2009) respectively. We did not use the tub2 region for our phylogenetic analyses because of the lack of sequences available in GenBank from this gene region in the family.…”