Video: How to Diagnose Onion Bacterial Bulb Rot

Bulb rot caused by bacterial pathogens can be confused with bulb rots caused by fungal pathogens as well as physiological disorders. It is important to accurately diagnose the cause of bulb rot/internal disorder in order to determine future effective preventative management strategies. In this simple 4 minute video, accurate identification of bulb rot caused by bacterial pathogens is distinguished from look-alikes caused by fungal pathogens Botrytis neck rot, Fusarium basal rot, black mold and blue mold and physiological disorders dry scale and translucent scale. It was produced by the CCE Cornell Vegetable Program for the Stop the Rot USDA-NIFA Project 2019-51181-30013. Available in both English and Spanish on the CCE Cornell Vegetable Program YouTube channel.
Video Transcript: How to Diagnose Bacterial Bulb Rot (pdf; 393KB)

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July 14, 2026
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A field walk will demonstrate pest management in fresh market vegetables in both field and greenhouse (high tunnel) vegetables, primarily for those growing for wholesale auction. CCE Cornell Vegetable Program Specialist Judson Reid will identify weeds, insects and diseases in vegetables and will go over management options such as inter-row cover crops, grafting, and where appropriate, spray options.
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Fillmore, NY
A field walk will demonstrate pest management in fresh market vegetables in both field and greenhouse (high tunnel) vegetables, primarily for those growing for wholesale auction. CCE Cornell Vegetable Program Specialist Judson Reid will identify weeds, insects and diseases in vegetables and will go over management options such as inter-row cover crops, grafting, and where appropriate, spray options.
DEC recertification credits available: 2.0 in categories 10, 1a, 23 and 24.
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