Cercospora fragariae

Fungal Disease

Cercospora fragariae

Fungal Disease

Cercospora fragariae

Fungal Disease

Cercospora leaf spot, caused by the fungus Cercospora fragariae, is a fungal disease affecting strawberry leaves. Though it is considered a minor pathogen in strawberries, its symptoms can be easily confused with other leaf diseases like common leaf spot (caused by Mycosphaerella fragariae).

Symptoms:

• In the early stages, small, circular leaf spots with uniformly purplish/reddish outer edges and very light (almost white) centers appear on the upper leaf surface. These spots are smaller and more irregular than those of common leaf spot.
• As the disease progresses, the necrotic centers of the spots become brittle and may fall out, creating a "shot hole" appearance. The spots remain relatively small and irregular but are surrounded by a dark-purple outer zone, and may occasionally merge.
• On the lower leaf surface, the spots appear bluish to tan and are more diffuse in appearance.

Spore Production and Spread:

• Spores are produced on the upper leaf surface within the white centers, which become dotted with small, dark knots of fungal cells.
• Like many fungal pathogens, C. fragariae spreads through water splashes, but it does not infect strawberry fruit.

Although Cercospora fragariae is considered a minor pathogen and does not affect strawberry fruit, it can still cause noticeable damage to the leaves. Early identification and management of leaf spot diseases are essential to maintain healthy plants and optimal yields.