Esca in young and mature vineyards, and molecular diagnosis of the associated fungi G. Romanazzi & S. Murolo & L. Pizzichini & S. Nardi Received: 16 July 2008 / Accepted: 16 April 2009 / Published online: 7 May 2009 # KNPV 2009 Abstract Esca is one of the most important grape- vine trunk diseases, and it can induce severe decline. In the past, the disease occurred mostly on mature vines, but today it is also present in young vineyards. The aim of this study was to investigate the incidence of esca in young (< 7 years old) and mature (> 11 years old) vineyards on cvs Montepulciano, Sangiovese, Verdicchio and Passerina located in the main viticultural areas of the Marche Region, central- eastern Italy. The average incidence of diseased plants was higher in mature (32.6%) than young (5.2%) vineyards, and Verdicchio and Passerina appeared to be the most sensitive among the cultivars considered, followed by Sangiovese and Montepulciano. The analysis of the spatial spread of esca carried out in two mature vineyards on cv. Verdicchio and a young vineyard on cv. Sangiovese showed a fluctuation in the numbers of infected plants over the three years of observation. The fungi associated with symptomatic plants were detected by classical and molecular tools. Isolation on agar media yielded colonies of Phaeo- moniella chlamydospora (Pch), Botryosphaeria spp. (Bot), Fomitiporia mediterranea (Fomed) and, spo- radically, Phaeoacremonium aleophilum (Pal). In samples from young plants, Bot and Pch were recurrent, while Pch and Fomed were found in mature vines and old rootstocks. Molecular detection with specific primer pairs for Pch, Pal, Fomed, and B. dothidea confirmed the data obtained using classical tools, and in some cases it was more sensitive. This study thus provides a further contribution to the association between causal agents and esca symp- toms, and it confirms the importance of molecular tools for a sensitive detection of associated pathogens, which can also be present in propagative materials. Keywords Botryosphaeria spp. . Botryosphaeria dothidea . Fomitiporia mediterranea . Phaeoacremonium aleophilum . Phaeomoniella chlamydospora Introduction Esca is a complex disease that has been described as one of the most important grapevine trunk diseases, and can induce severe decline and dieback. Research on its etiology, which started at the end of the XIX century in France, continued from the beginning of 1900 in Italy and in California, USA, and was intensified further in Eur J Plant Pathol (2009) 125:277–290 DOI 10.1007/s10658-009-9481-8 G. Romanazzi (*) : S. Murolo Department of Environmental and Crop Science, Marche Polytechnic University, Via Brecce Bianche, 60131 Ancona, Italy e-mail: g.romanazzi@univpm.it L. Pizzichini : S. Nardi Servizio Fitosanitario – ASSAM, Regione Marche, Via Alpi, 21, 60131 Ancona, Italy