A new wood-decaying basidiomycete species associated with esca of grapevine: Fomitiporia mediterranea (Hymenochaetales)

Abstract

Fomitiporia mediterranea is described as a new wood-decaying basidiomycete species associated with esca of grapevine in European wine-growing countries. Characters of the fruit body are essentially identical with those of the closely related species, Fomitiporia punctata. Fomitiporia mediterranea is distinct by the sequences of the ribosomal ITS1-5.8S-ITS2 region and by larger mycelial growth rates at temperatures between 15 °C and 35 °C. While F. punctata is confirmed as a homothallic species, F. mediterranea is shown to be outcrossing, exhibiting a unifactorial mating behaviour with a multiple allelism of the mating type factor, A; single spore isolates of F. mediterranea are intersterile in pairing tests with F. punctata. In southern Europe, F. mediterranea not only occurs on Vitis vinifera, but also on a number of other hardwood genera; it seems restricted to Vitis vinifera elsewhere in Europe.