Novel Cryphonectriaceae from La Réunion and South Africa, and their pathogenicity on Eucalyptus
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Fungi in the Cryphonectriaceae are important canker pathogens of plants in the Melastomataceae and Myrtaceae (Myrtales). These fungi are known to undergo host jumps or shifts. In this study, fruiting structures resembling those of Cryphonectriaceae were collected and isolated from dying branches of Syzygium cordatum and root collars of Heteropyxis natalensis in South Africa, and from cankers on the bark of Tibouchina grandifolia in La Réunion. A phylogenetic species concept was used to identify the fungi using partial sequences of the large subunit and internal transcribed spacer regions of the nuclear ribosomal DNA, and two regions of the β-tubulin gene. The results revealed a new genus and species in the Cryphonectriaceae from South Africa that is provided with the name Myrtonectria myrtacearum gen. et sp. nov. Two new species of Celoporthe (Cel.) were recognised from La Réunion and these are described as Cel. borbonica sp. nov. and Cel. tibouchinae sp. nov. The new taxa were mildly pathogenic in pathogenicity tests on a clone of Eucalyptus grandis. Similar to other related taxa in the Cryphonectriaceae, they appear to be endophytes and latent pathogens that could threaten Eucalyptus forestry in the future.
KeywordsDiaporthales Die-back Myrtales New taxa Stem canker Tree disease Taxonomic novelties: Myrtonectria myrtacearum gen. et sp. nov., Celoporthe borbonica sp. nov., Celoporthe tibouchinae sp. nov.
We thank the members of the Tree Protection Co-operative Programme (TPCP), the THRIP initiative of the Department of Trade and Industry, and the Department of Science and Technology (DST)/National Research Foundation (NRF) Centre of Excellence in Tree Health Biotechnology (CTHB) for financial assistance that made this study possible.
- Conradie E, Swart WJ, Wingfield MJ (1990) Cryphonectria canker of Eucalyptus, an important disease in plantation forestry in South Africa. South Afr For J 152:43–49Google Scholar
- Gryzenhout M, Myburg H, van der Merwe NA, Wingfield BD, Wingfield MJ (2004) Chrysoporthe, a new genus to accommodate Cryphonectria cubensis. Stud Mycol 50:119–141Google Scholar
- Gryzenhout M, Myburg H, Wingfield BD, Montenegro F, Wingfield MJ (2005a) Chrysoporthe doradensis sp. nov. pathogenic to Eucalyptus in Ecuador. Fungal Divers 20:39–57Google Scholar
- Gryzenhout M, Wingfield BD, Wingfield MJ (2009) Taxonomy, phylogeny, and ecology of bark-inhabiting and tree-pathogenic fungi in the Cryphonectriaceae. American Phytopathological Society, MinnesotaGoogle Scholar
- Katoh K, Asimenos G, Toh H (2009) Multiple alignment of DNA sequences with MAFFT. Bioinformatics for DNA sequence analysis. Posada D, Humana Press 537:39–64Google Scholar
- Rayner RW (1970) A mycological colour chart. Commonwealth Mycological Institute, Kew, SurreyGoogle Scholar
- SAS_Institute_Inc (1999) SAS/STAT ® User’s Guide, Version 8. SAS Institute Inc, Cary, NCGoogle Scholar
- White TJ, Bruns TD, Lee S, Taylor JW (1990) Amplification and direct sequencing of fungal ribosomal RNA genes for phylogenetics. In: Innis MA, Gelfand DH, TJ SJJW (eds) PCR protocols: a guide to methods and applications. Academic Press Inc., San Diego, pp 315–322Google Scholar