Interaction between root rot basidiomycetes and Phytophthora species on pedunculate oak

Benoit Marçais (1) , O. Caël (1) , C. Delatour (2)

1 IAM - Interactions Arbres-Microorganismes
2 NANCY ECOSYST FOR - Ecosystèmes Forestiers : Microbiologie, Pathologie et Biogéochimie

Forest declines are usually complex multifactorial phenomena that involve interactions between different factors. While interactions between insects and pathogens have been shown to often be of primary importance, the possible interaction between different types of pathogens has not yet been investigated. Through artificial inoculation on oak seedlings, we studied the interaction between two root rot basidiomycetes, Collybia fusipes and Armillaria mellea and two Phytophthora species, P. cinnamomi and P. cambivora. These pathogens were inoculated onto young Quercus robur saplings in greenhouse conditions, either alone or combining a root rot basidiomycete with a Phytophthora species. Three out of the four Phytophthora * root rot basidiomycete combinations tested resulted in damages to oak host significantly larger than the sum of the damages induced by the pathogens on their own. This positive interaction could be significant in the oak decline syndrome.

Mots clés: forest tree; decline; oak; Key word: root rot basidiomycete; Phytophthora

Domaines: Phytopathologie et phytopharmacie; Mycologie; Interactions entre organismes

Benoit Marçais, O. Caël, C. Delatour. Interaction between root rot basidiomycetes and Phytophthora species on pedunculate oak. Plant Pathology, 2011, 60 (2), pp.296-303. ⟨10.1111/j.1365-3059.2010.02378.x⟩. ⟨hal-02068541⟩