Submitted to: Mycological Progress
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 4/8/2005
Publication Date: 8/1/2005
Citation: Glawe, D.A., Dugan, F.M., Liu, Y., Rogers, J.D. 2005. First record and characterization of a powdery mildew on a member of the juncaginaceae: leveillula taurica on triglochin maritima.. Mycological Progress. 4:291-298. Interpretive Summary: The broad host range powdery mildew fungus, Leveillula taurica, was reported from British Columbia and Washington State in 2003 (on greenhouse pepper) and 2004 (on onion and potato), respectively. It was not previously reported in this geographic area. With this manuscript, the fungus is also reported on greenhouse-grown seaside arrowgrass (Triglochin maritima, of the family Juncaginaceae) from Washington State. T. maritima is best known as a plant toxic to young livestock because it produces hydrogen cyanide. Leveillula taurica is recorded from numerous plant species, nearly all (except onion) dicots. Triglichin is a monocot. This represents the first report of a powdery mildew on a member of the Juncaginaceae. The recent cluster of report of L. taurica in the Pacific Northwest suggests the possibility that L. taurica is an emerging pathogen in this region. We used light microscopy, scanning electron microscopy and molecular-genetic data to establish the identity of the fungus.
Technical Abstract: The powdery mildew fungus Leveillula taurica (Erysiphales) is reported for the first time from Triglochin maritima (Jungacinaceae), a widespread salt marsh plant that causes economic losses because of its high toxicity to young livestock. This is the first report of a powdery mildew fungus on a member of the Jungacinaceae. Morphological data, obtained by light and scanning electron microscopy, and ITS sequence data provided evidence that this fungus is referable to L. taurica.The ITS sequence for this fungus was identical with those reported for L. taurica attaching Capsicum annuum in Australia and Elaeagnus angustifolia in Iran. This is the third host species, in addition to Allium cepa and Solanum tubersom, reported for Leveillula taurica from Washington State, where the fungus was unreported before 2004.