Black Rot
A fungal disease of apple caused by Botryosphaeria obtusa, affecting leaves, fruit, and wood.
Affected Plant
Apple
Severity
Moderate
Symptoms
- Purple-bordered circular leaf spots ("frogeye leaf spot")
- Brown to black rotted areas on fruit with concentric rings
- Sunken cankers on branches and limbs
- Fruit may shrivel into hard "mummies"
Causes
- Fungal infection by Botryosphaeria obtusa
- Entry through wounds, dead wood, or old cankers
- Warm, humid weather favoring fungal spread
Prevention
- Prune out dead, diseased, or cankered wood
- Remove mummified fruit from the tree and ground
- Maintain overall tree vigor and good sanitation
Management
- Apply fungicide programs where warranted, per local extension guidance
- Promptly remove and destroy infected plant material
Related Apple Diseases
Think your plant might have Black Rot?
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Diagnose Your PlantDisclaimer: This is an AI-generated result and not a replacement for expert agronomic or plant-pathology diagnosis. Confidence scores reflect the model's certainty, not biological ground truth. The model was trained and evaluated on leaf photos captured under controlled, lab-like conditions, so accuracy on real-world field photos (cluttered backgrounds, variable lighting, multiple or overlapping leaves) may be lower than the reported evaluation metrics.