Neofabraea species associated with bull’s-eye rot and cankers of apple and pear in the Pacific Northwest

Species-specific primers for four species of Neofabraea associated with apple and pear fruit diseases were used in multiplex PCR assays to identify 29 putative Neofabraea isolates, primarily isolated from bull’s-eye rot on pears from packing houses in Washington and Oregon. Apples were inoculated with these isolates, and tentative identifications based on morphology of conidia forming on wound-inoculated fruits were compared with identifications made using species-specific primers for different Neofabraea species. PCR-based identifications were successful for 26 of 29 isolates, and in all cases were consistent with tentative identifications based on spore morphologies. The results revealed that in addition to the two species of Neofabraea already known to occur in the Pacific Northwest, N. malicorticis and N. perennans, a third species, N. alba, is also prevalent.