Submitted to: Canadian Journal of Botany
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: November 12, 2002
Publication Date: November 30, 2002
Citation: Rossman, A.Y., Farr, D.F., Castlebury, L.A., Shoemaker, R., Mengistu, A. 2002. Setomelanomma holmii (pleosporales, phaeosphaeriaceae) on living spruce twigs in europe and north america. Canadian Journal of Botany. Vol.80(11)pp.1209-1215,2002. Interpretive Summary: A very small fungus is killing spruce trees in Wisconsin. This fungus was examined carefully using a microscope and grown in the laboratory. It was compared to a fungus described on spruce trees in France and determined to be the same species. In searching among previously collected specimens, the fungus was also found to exist in Kansas and Ontario, Canada. In addition, isolates of this fungus from the United States and France were compared and characterized using molecular sequences. This fungal species on spruce trees was thoroughly described, illustrated and compared with related species. This research will allow plant pathologists to identify the fungus on spruce and distinguish it from similar looking fungi.
Technical Abstract: Setomelanomma holmii M. Morelet, previously known only from the type specimen in France, was discovered in the United States (Kansas and Wisconsin) and Canada (Ontario) on living twigs of spruce (Picea pungens and P. glauca). This fungus was grown from ascospores and compared with the ex-holotype culture. Morphology and ITS rDNA sequence similarities indicate that S. holmii belongs in the Pleosporales, Phaeosphaeriaceae. Sequence analysis of the small subunit nuclear ribosomal DNA places S. holmii in a clade containing members of the Leptosphaeriaceae and Phaeosphaeriaceae. Setomelanomma holmii is redescribed and illustrated based on the holotype and North American specimens.