Erysiphe biuncinata

Erysiphe biuncinata is a species of powdery mildew in the family Erysiphaceae. It is found in North America, where it affects the genus Hamamelis.

Description

The fungus forms a patchy white coating on host leaves, often around main veins. E. biuncinata, like most Erysiphaceae, is highly host-specific and infects only the genus Hamamelis. Another species of powdery mildew also infects this genus: Phyllactinia hamamelidis, which has weak, very thin, often smooth growth, on the undersides of leaves.

Taxonomy

The fungus was formally described in 1872 by Cooke and Peck with the basionym Podosphaera biuncinata. The species was transferred to the genus Erysiphe by Bradshaw et al. in 2024.