First Report of Marssonina brunnea f. sp. brunnea on Hybrid Poplar in the Pacific Northwest

Marssonina brunnea (Ellis and Everh.) Magnus f. sp. brunnea Spiers is the most damaging Marssonina sp. affecting Populus spp. in the world (1). First described from eastern North America at the turn of the century, it subsequently became a serious disease of hybrid poplar in Europe in the 1960s and...

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Veröffentlicht in:Plant disease. - 1997. - 81(1997), 2 vom: 30. Feb., Seite 231
1. Verfasser: Newcombe, G (VerfasserIn)
Weitere Verfasser: Callan, B E
Format: Online-Aufsatz
Sprache:English
Veröffentlicht: 1997
Zugriff auf das übergeordnete Werk:Plant disease
Schlagworte:Journal Article
Beschreibung
Zusammenfassung:Marssonina brunnea (Ellis and Everh.) Magnus f. sp. brunnea Spiers is the most damaging Marssonina sp. affecting Populus spp. in the world (1). First described from eastern North America at the turn of the century, it subsequently became a serious disease of hybrid poplar in Europe in the 1960s and in New Zealand in 1976 (1). It causes punctiform black spots on both leaf surfaces and lesions on petioles and young stems. Symptoms are typically most severe in the lower portion of the crown of trees. Not observed in the Pacific Northwest on hybrid poplar until recently, it is still only present in a few locations. Voucher specimens from near Ilwaco, WA, at the mouth of the Columbia River, and from near Har-rison Mills, British Columbia, were deposited in the Herbarium at the Pacific Forestry Centre (DAVFP 25202 and 24958, respectively). The fungus was identified as M. brunnea by its conidial morphology. Conidia were hyaline, uniseptate, mostly straight, and narrowly obovoid, and, when measured in lactoglycerol, averaged 16.1 μm × 5.0 μm (WA collection) and 15.7 μm × 5.6 μm (BC collection). The septum is located about 30% of the total conidium length from the conidium base. Inoculations of leaf disks (1) proved that the species was pathogenic to hybrids but not to local P. tremuloides Michx., and thus the fungus was identified as M. brunnea f. sp. brunnea. Variation in resistance, from light spotting to severe, was noted both among 12 P. trichocarpa Torr. & A. Gray × P. deltoides J. Bartram ex. Marsh. hybrid clones in the Ilwaco plantation and among 56 hybrid clones in the inoculation study. Reference: (1) A. G. Spiers. Eur. J. For. Pathol. 18:140, 1988
Beschreibung:Date Revised 20.11.2019
published: Print
Citation Status PubMed-not-MEDLINE
ISSN:0191-2917
DOI:10.1094/PDIS.1997.81.2.231B