Parasitic fungi on leaves of black cherry: a contribution to biological plant protection.
Four fungus species occurring on Wild Black Cherry (Prunus serotina) are described, including their symptoms and taxonomic and infection biology characteristics. Asteroma padi is considered to be the causative agent of light-brown leaf spots. The fungus has an endophytic stage of development, which can change into a pathogenic phase caused be feeding of insect larvae. Paecilomyces crassipes sp. nov. is described here for the first time as a new species. Phoma pomorum is causing symptoms similar to Asteroma padi, but differentiated by smaller spores. Taphrina farlowii, known as "lost species", causes bubble-like, conspicuously coloured deformations on young leaves. This article raises the question whether one of the mentioned fungi can be applied as "mycoherbicide" against the spreading of Prunus serotina.