Pathogenicity, Molecular Characterization, and Mycotoxigenic Potential of spp. Agents of Black Spots on Fruit and Leaves of in Italy.

Brown and black spots, caused by and species, are important fungal diseases affecting European pear () in orchards. Both fungal genera cause similar symptoms, which could favor misidentification, but spp. are increasingly reported due to the changing climatic conditions. In this study, spp. were isolated from symptomatic leaves and fruits of European pear, and their pathogenicity was evaluated on pear fruits from cultivar Abate Fétel, and molecular and chemical characterization were performed. Based on maximum likelihood phylogenetic analysis, 15 of 46 isolates were identified as species complex (AASC), 27 as , and four as sp. Both species were isolated from mature fruits and leaves. In pathogenicity assays on pear fruits, all isolates reproduced the symptoms observed in the field, by both wound inoculation and direct penetration. All but one isolate produced toxins on European pears, including tenuazonic acid and alternariol (89.1% of the isolates), alternariol monomethyl ether (89.1%), altertoxin I (80.4%), altenuene (50.0%), and tentoxin (2.2%). These isolates also produced at least two mycotoxins, and 43.5% produced four mycotoxins, with an average total concentration of the toxins exceeding 7.58 × 10 ng/kg. Our data underline the potential risks for human health related to the high mycotoxin content found on fruits affected by black spot. This study also represents the first report of AASC as an agent of black spot on European pear in Italy.