Phytopathological problems in Italy on high-value broadleaved trees.
The occurrence in Italy of the main widespread abiotic and biotic diseases of Acer, Alnus, Fraxinus, Juglans, Prunus and Quercus, in stands recently planted for high quality timber production, are reported. The severe attacks of anthracnosis (Gnomonia leptostyla) and black spots (Xanthomonas campestris pv. juglandis [Xanthomonas arboricola pv. juglandis]) on walnut; corineum blight (Sporocadus carpophilum [Blumeriella jaapii]) and, above all, leaf spot (Cylindrosporium padi) on wild cherry; powdery mildews (Uncinula aceris) on maple; Microsphaera alphitoides on oaks; and Phyllactinia guttata on ash, are briefly described. Stem and twig cankers by several pathogens are present in suffering plantations. Verticillium vascular wilts and Phytophthora root rots, particularly on walnut, cherry and alder, will increase in the future. Some control measures are briefly described.