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)


Upcoming Events
Vegetable Pest and Cultural Management Field Meeting for Auction Growers -- Ontario Produce Auction

July 15, 2025
Stanley, NY
This evening meeting will demonstrate pest management in fresh market vegetables in both field and greenhouse (high tunnel) vegetables, primarily for those growing for wholesale auction. A hands-on demonstration of weed, insect and disease identification in vegetables including management options. Details on each topic will focus on field observations at the farm.
Orleans Summer Vegetable Meeting, 2025

July 16, 2025
Waterport, NY
Meeting themes are pest management in a wide array of produce and best practices for pesticide use. Professor Brian Nault will cover allium leaf miner and thrips in onions, garlic, and leeks, and discuss insect challenges in other crops. Bring your questions! We'll also have a field walk that includes high tunnel tomato and cucumber.
DEC credits available: 0.5 in CORE plus either 1.25 in 1a and 23, or 0.75 in 24.
Vegetable Pest and Cultural Management Field Meeting for Auction Growers -- Finger Lakes Produce Auction

July 18, 2025
Penn Yan, NY
This evening meeting will demonstrate pest management in fresh market vegetables in both field and greenhouse (high tunnel) vegetables, primarily for those growing for wholesale auction. A hands-on demonstration of weed, insect and disease identification in vegetables including management options. Details on each topic will focus on field observations at the farm.