Inoculation of Oak (Quercus robur and Q. rubra) with Collybia fusipes. Benoit Marcais, Laboratoire de Pathologie forestiere, Institut National de la Recherche Agronomique, F54280 Champenoux. Claude Delatour, Laboratoire de Pathologie forestiere, Institut National de la Recherche Agronomique, F54280 Champenoux. Plant Dis. 80:1391-1394. Accepted for publication 4 September 1996. This article is in the public domain and not copyrightable. It may be freely reprinted with customary crediting of the source. The American Phytopathological Society, 1996. DOI: 10.1094/PD-80-1391.

Collybia fusipes has been reported as the cause of a root rot disease of oak trees in Europe. The pathogenicity of this fungus has not yet been proven by inoculation. C. fusipes was able to survive for more than 1 year in hazel stem segments or on oak root segments buried in nonsterile soil, provided these wood segments were incubated with the fungus for as long as 10 months before burial. We conducted three inoculation trials with 2-year-old oak seedlings. Inoculation success was strongly linked to the ability of C. fusipes to survive in the inoculum. The fungus was able to induce substantial lesions (5 to 20 cm2) in two growing seasons on vigorous seedlings, but none of the inoculated seedlings died in the course of the experiments. Defoliating seedlings for 2 years in a row did not increase the susceptibility to C. fusipes.