Charcoal canker of pear, plum, and quince trees caused by Biscogniauxia rosacearum sp. Nov. in southern Italy

The genus Biscogniauxia is paraphyletic to Xylariaceae, and includes at least 52 species to date that are mainly pathogens of dicotyledonous angiosperm trees. Most of these are forest trees, such as Acacia, Acer, Alnus, Eucalyptus, Fraxinus, Populus, Quercus and other species of minor importance. Biscogniauxia species have been reported as endophytes or secondary invaders that attack only stressed plants. During a survey in Rosaceae orchards in southern Italy, several charcoal cankers were observed and stroma samples were collected. A collection of 31 Biscogniauxia isolates were analyzed. Their phylogenetic relationships were determined through study of internal transcribed spacer, β-tubulin and actin gene sequences. Combining morphological, culture and molecular data, a new species of Biscogniauxia is described here as B. rosacearum. This new species is isolated for the first time from Rosaceae hosts in Apulia. The pathogenicity tests show that it causes symptoms on stems when artificially inoculated, and produces stromata on the bark surface.