Inonotus rickii (Pat.) D. Reid (Hymenochaetaceae), widespread in tropical and subtropical countries, produces cankers and decay in several hardwoods. In Italy, it was recorded for the first time approximately 20 years ago on Parkinsonia sp. and Schinus molle L. in Sicily (2) and more recently on Acer negundo L. and Celtis australis L. in Rome (1). During May 2004, a survey was performed in Sicily in public and botanical gardens where the fungus had been detected in the past. Although the previously attacked plants had been removed, more trees were showing decline symptoms, with sparse foliage and some dieback. Typical brown, powdery masses of chlamydospores of I. rickii were observed near wounds or pruning cuts on Quercus cerris L. in Palermo and Sambucus nigra L. and Aberia caffra Hook. F. & Harv. in Catania. From each fungal specimen, fragments were isolated and cultured on malt agar. Cultures produced acute, thick-walled, brown setae (as much as 250 µm long) and abundant chlamydospores that were yellowish brown, thick walled, irregularly shaped, and 10 to 12 × 8 to 12 µm. Each isolate conformed to I. rickii (3). Cultures and voucher specimens have been deposited in the ISPaVe collection (PF40, PF41, and PF42) and the ROPV herbarium (772, 773, and 774). To our knowledge, this is the first report of I. rickii in living Q. cerris and A. caffra. S. nigra is a new host in Italy. This record shows that the pathogen has fully established itself in southern Europe where it may expand its host range.
References: (1) T. Annesi et al. For. Pathol. 33:405, 2003. (2) M. Intini. Micol. Ital. 20:49, 1988. (3) J. A. Stalpers. Karstenia 40:167, 2000.
