Taphrina deformans

A very aggressive fungus affecting living leaves of stone fruit trees, especially peach trees, causing conspicuous blisters and severe leaf curling and deformations of a striking intense red colour.

Mycelium developing within the leaf tissue, intercellular, filamentous and hyaline.

Few microscopic features to observe, only clavate asci arranged in a palisade, initially 8-spored; these 8 spores frequently begin to multiply by budding, leaving the ascus packed with small spherical spores 2 to 5 µm in diameter.

Mature ascospores ellipsoidal, smooth, hyaline, thin-walled, 6 to 10 µm long and 3 to 5 µm wide.