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Mycosphaerella leaf spot

Mycosphaerella pyri (Auersw.) Boerema

Lesions are primarily circular, 3–5 mm in diameter, and have a grayish white interior, with a distinct purple margin; small, black pycnidia develop in the interior of older lesions (A). The fungus occasionally attacks the fruit, producing small, dark lesions.


Widespread, although of minor economic importance in sprayed commercial orchards.

Similar Species

The disease can be confused with Fabraea leaf spot; Fabraea lesions tend to be darker.


Fungicide programs targeting Fabraea leaf spot will effectively control Mycosphaerella leaf spot.

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