Compendium of pistachio diseases in Italy

Pistachio (Pistacia vera) is an important crop in Italy, especially in Sicily (southern Italy), due to the suitability of the crop to the agro-ecological conditions. However, the phytopathological situation has been poorly investigated and little information is available. My research has focused on the investigation of fungal diseases affecting pistachio in Italy. Field surveys were conducted in different geographic regions of Sicily. Symptomatic samples, including leaves, fruit panicles and shoots, were brought to the laboratory and fungal pathogens were isolated and stored in our laboratory fungal collection. Morphological and molecular characterization, based on the multilocus phylogenetic analyses, were conducted on representative isolates. Pathogenicity tests were performed to fulfill Koch’s postulates. Our results revealed that canopy diseases are the major issues for this crop, including Septoria leaf spot (Septoria pistaciarum), which is the most widespread disease, and Botryosphaeria panicle and shoot blight caused by Botryosphaeriaceae species, such as Botryosphaeria dothidea, Neofusicoccum hellenicum and N. mediterraneum. Canker pathogens were also identified including Leptosillia pistaciae (ex Liberomyces pistaciae), which causes pistachio dieback, and Cytospora pistaciae and Eutypa lata, which sporadically caused canker and gummosis. Moreover, the fungus Arthrinium xenocordella was reported, which is known to cause fruit blight, but this is only a minor disease. Further research will be needed to detect new diseases that may limit the cultivation of pistachio in Italy as well as in the Mediterranean basin.

Giorgio Gusella won the ISHS Young Minds Award for the best oral presentation at the VIII International Symposium on Almonds and Pistachios in USA in May 2023.

Giorgio Gusella, Dipartimento di Agricoltura, Alimentazione e Ambiente, University of Catania, Via Santa Sofia 100, 95123 Catania, Italy, e-mail: giorgio.gusella@unict.it

The article is available in Chronica Horticulturae