First report of powdery mildew caused by Erysiphe platani in Ailanthus altissima , the tree-of-heaven, in the Mediterranean basin, Italy

In August 2018, a tree-of-heaven ( Ailanthus altissima ) showing symptoms of powdery mildew was found in Pisa, Italy. Morphological characteristics of the anamorph and molecular sequence analysis of the internal transcribed spacer region of rDNA verified the fungus as Erysiphe platani. In a pathogenicity test, powdery mildew patches were present on leaf surfaces 2 weeks after inoculation with the isolate. This is the first report of E. platani causing powdery mildew on ailanthus in the Mediterranean basin. The fungus, whose historical host range was confined to the genus Platanus, has expanded its host range to Ailanthus in Italy.