Systematic reappraisal of Coniella and Pilidiella, with specific reference to species occurring on Eucalyptus and Vitis in South Africa

Date
2004
Authors
Van Niekerk J.M.
Groenewald J.Z.E.
Verkley G.J.M.
Fourie P.H.
Wingfield M.J.
Crous P.W.
Journal Title
Journal ISSN
Volume Title
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Abstract
The genus Pilidiella, including its teleomorphs in Schizoparme, has a cosmopolitan distribution and is associated with disease symptoms on many plants. In the past, conidial pigmentation has been used as a character to separate Pilidiella (hyaline to pale brown conidia) from Coniella (dark brown conidia). In recent years, however, the two genera have been regarded as synonymous, the older name Coniella having priority. To address the generic question, sequences of the internal transcribed spacer region (ITS1, ITS2), 5.8S gene, large subunit (LSU) and elongation factor 1-α gene (EF 1-α) were analysed to compare the type species of Pilidiella and Coniella. All three gene regions supported the separation of Coniella from Pilidiella, with the majority of taxa residing in Pilidiella. Pilidiella is characterised by having species with hyaline to pale brown conidia (avg. length:width >1.5), in contrast to the dark brown conidia of Coniella (avg. length:width ≤1.5). Pilidiella diplodiella, which is a pathogen associated with white rot of grapevines, was shown to be an older name for C. petrakii. To delineate species in the P. diplodiella species complex, isolates were also compared based on histone (H3) gene sequences. Analyses derived from these sequence data separated P. diplodiella from a newly described species, P. diplodiopsis. The new species P. eucalyptorum sp. nov. is proposed for isolates formerly treated as C. fragariae and associated with leaf spots of Eucalyptus spp. This species clustered basal to Pilidiella, and may represent yet a third genus within this complex. Pilidiella destruens sp. nov. is newly described as anamorph of Schizoparme destruens, which is associated with twig dieback of Eucalyptus spp. in Hawaii. A key based on morphological characteristics is provided to separate the taxa treated in this study.
Description
Keywords
elongation factor 1, fungal DNA, ribosomal spacer DNA, ribosome DNA, RNA 5.8S, fungus, new species, taxonomy, article, Ascomycetes, classification, DNA sequence, Eucalyptus, genetics, grape, microbiological examination, microbiology, molecular genetics, nucleotide sequence, phylogeny, plant disease, South Africa, Ascomycota, DNA, Fungal, DNA, Ribosomal, DNA, Ribosomal Spacer, Eucalyptus, Molecular Sequence Data, Mycological Typing Techniques, Peptide Elongation Factor 1, Phylogeny, Plant Diseases, RNA, Ribosomal, 5.8S, Sequence Analysis, DNA, South Africa, Vitis, Africa, South Africa, Southern Africa, Sub-Saharan Africa, Ascomycota, Coniella, Eucalyptus, Fungi, Pilidiella, Pilidiella eucalyptorum, Schizoparme, Vitis, Vitis sp.
Citation
Mycological Research
108
3