Cryptostroma corticale in Italy: new reports of sooty bark of Acer pseudoplatanus and first outbreak on Acer campestre

Monitoring of emerging plant diseases in the Apennine mountains (central Italy) identified Cryptostroma corticale as the cause of the disease sooty bark of maple trees. The identified sites were located in rural or forested areas, next to buildings, in villages or suburbs, and one site was in a forest. Samples of symptomatic tissues were taken from Acer pseudoplatanus and/or A. campestre, as well as asymptomatic samples from A. campestre and Aesculus hippocastanum. All samples tested positive to a species-specific qPCR assay for the presence of C. corticale, indicating wide incidence of the disease in the northern Apennines of Italy, after attempted eradication of the first small group of infected plants were found in 2012.