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Widespread and locally severe foliar symptoms resembling Dothistroma Needle Blight (DNB), one of the most important infectious diseases of forest trees worldwide, were recently observed in La Sila Massif, a mountain plateau covered with native forests of Pinus nigra subsp. laricio in La Sila National Park, Southern Italy. At the same time, DNB symptoms were observed in Pinus cembra and Pinus mugo forests in the Paneveggio-Pale di San Martino Nature Park and in Val Sarentino, Northeastern Italy. Defoliation was extensive at all sites and severe on the majority of plants of affected species, both adult trees and renovation. In particular on Pinus cembra, the disease was so serious as to locally threaten the species' reproduction and survival, an unusually heavy damage on this host. Species-specific real time PCR diagnostics, recommended by EPPO, was applied to needle samples from these sites and the presence of Dothistroma septosporum was ascertained, while Dothistroma pini, the morphologically identical congeneric species causing the same disease, was not detected. The pathogen was isolated from conidiomata and species attribution was confirmed by sequencing of the ITS region. In addition, a culture independent survey based on the same molecular assays was carried out in other areas of Northern, Central and Southern Italy, where pines of various species were affected by similar symptoms, and gave negative results for both Dothistroma species. Results show that D. septosporum currently has in Italy a much larger distribution and host range than reported and is associated to life-threatening damage to native pine species growing in established populations for in situ conservation of genetic resources, which would require an update of specific conservation actions.

Wild herbaceous dicotyledonous plants (dicots) showing symptoms ascribable to phytoplasma disorders were found to be widely distributed in organic vineyards in central Tuscany (Italy) affected by bois noir, a grapevine yellows disease caused by “Candidatus Phytoplasma solani”. In 2010 symptomatic dicots were tentatively identified to species level and the incidence of symptoms estimated in two selected vineyards in the province of Florence. Incidence ranged from 2 to 77%, and was not related to the relative abundance of hosts since very common species as well as relatively rare ones were consistently found to be symptomatic. PCR indexing and 16S rRNA sequence analyses indicated that two phytoplasmas co-existed in the vineyards: “Ca. P. solani”, infecting the root systems of 17 taxa, and a phytoplasma closely related to “Ca. P. phoenicium”, infecting 11 taxa, and occasionally co-infecting the same plant. Regardless of the high frequency of both pathogens in the vineyards, only “Ca. P. solani” could be detected in the grapevines. Population screening by means of tuf sequence analyses revealed the presence of only the tuf-b “Ca. P. solani” type both in dicot hosts and grapevine. This supports current notions of bois noir epidemiology, indicating that some infected dicots act as sources of “Ca. P. solani” inoculum whereas others are dead-end hosts. When the same specimens were screened by sequence analysis of the vmp1 gene, evidence was found that different phytoplasma genotypes may be predominant in grapevines and dicots.