Strawberries: Leaf Spot | Berry Diagnostic Tool

Leaf spot

The fungus Mycosphaerella fragariae causes an infection which starts off as small purple spots on leaves. Later, spots have a narrow whitish to grayish margin. Sometimes lesions centers drop out, giving leaves a “shot-hole” appearance.

Strawberry leaf with irregularly distributed spots. Spots have brown border and white center that occasionally falls out to make holes.

Strawberry leaf with reddish discoloration in v-shape starting from outer margins. Brown-bordered spots with white center scattered across leaves.

Fruit infections may also occur with this fungus. They are called “black seed” as the infections center around individual seeds (achenes).

Ripe strawberry fruit with small, sunken, black tissue surrounding 1-3 seeds.

Stem lesions may also be evident on leaf petioles and runners.

Strawberry stem with black cankerous lesion spreading to immature rootlets. Leaves sprouting from stem have necrotic tissue in v-shape pattern starting at tips.

More information:

Reports on Plant Diseases – Strawberry Leaf Diseases – (University of Illinois)
Strawberry Leaf Spot (Ohio State)
Strawberry Leaf Spot (OMAFRA)

Use these resources if you need additional help with diagnosis and to find solutions to your problem.