Strawberries: Fruit show sunken black spots after warm, wet weather (Anthracnose)

Anthracnose fruit rot

Anthracnose fruit rot, caused by the fungus Colletotrichum acutatum, occurs on strawberries during periods of warm wet weather. It is particularly prevalent on late season June-bearing and day-neutral strawberry varieties. Anthracnose spreads very quickly, especially where plastic mulch is used.

The disease may occur on both green and ripe fruit.

Cluster of ripening strawberry fruit. Unripe berries have multiple small, brown spots. Spots cover achenes and achene in center of rotted region is brown.

Look for one or more circular spots on the fruit.

Ripe strawberry fruit marked with multiple sunken brown spots.

Spots originally are tan or light brown but become darker and sunken.

Ripe strawberry fruit half-covered in anthracnose rot. Rot begins at fruit tip and extends toward cap. Rot is dry and brown with black areas. Achenes in rotted region are brown and black.

Sunken spots are usually about one eighth to one quarter inch in diameter and may be covered with pink slimy spore masses during wet or very humid periods.

Heavily rotted ripe strawberry fruit with pinkish areas on black sections of rot.

More Anthracnose information:

Anthracnose of Strawberry – (Ohio State)
Anthracnose of Strawberry – (University of Alabama)