Forsythia: A New Host of Phytophthora nicotianae in Italy. S. O. CACCIOLA, Institute of Plant Pathology, University of Catania, 95123 Catania, Italy. A. BELISARIO, Laboratory of Plant Pathology, Agricultural and Forest Research Centre S.A.F./E.N.C.C, Via Casalotti 300, 00166 Rome, Italy; and A. PANE and G. MAGNANO DI SAN LIO, Institute of Plant Pathology, University of Catania, 95123 Catania, Italy. Plant Dis. 78:525-528. Accepted for publication 16 November 1993. Copyright 1994 The American Phytopathological Society. DOI: 10.1094/PD-78-0525.

During the summer of 1990, seedlings of forsythia (Forsythia viridissima), grown in pots in a production nursery in Campania (Italy), showed symptoms of decline associated with root and crown rot. Phytophthora nicotianae of A2 mating type was isolated from decayed tissues. Identification of the isolate was based on both morphological and physiological characters, and on the electrophoretic pattern of total native mycelial proteins. P. nicotianae was confirmed as the causal agent of this decline by fulfilling Koch's postulates. Seedlings of forsythia inoculated with the P. nicotianae isolate developed symptoms identical to those observed in natural infec-lions. The species inoculated was reisolated from the basal stem and roots of symptomatic seedlings. This is the first report of P. nicotianae as a pathogen of forsythia.