2022 Cornell Onion Fungicide Cheat Sheets for Control of Leaf Diseases
Christy Hoepting, Extension Vegetable Specialist
Cornell Vegetable Program
This sheet provides relative performance rankings for Botrytis leaf blight and Stemphylium leaf blight of the main fungicide options that may be used in New York to control these diseases, based on recent on-farm fungicide trial results, which reflect reduced efficacy of SLB due to development of fungicide resistance.
The 2022 Onion Fungicide Cheat Sheet for Control of Leaf Diseases in New York includes active ingredients, FRAC codes, rating for risk of fungicide resistance, activity on downy mildew, and maximum use rates.
The 2022 Relative Performance of Fungicides Including Tank Mixes for Control of Botrytis Leaf Blight and Stemphylium Leaf Blight Cheat Sheet provides an easy-to-read ranking of the relative efficacy of the treatment options and their FRAC groups.
2022 Onion Fungicide Cheat Sheet for Control of Leaf Diseases in New York (pdf; 302KB)
2022 Performance of Fungicides Including Tank Mixes for Control of BLB and SLB (pdf; 276KB)


Upcoming Events
Vegetable Pest and Cultural Management Meeting for Auction Growers (Ontario)

June 27, 2023
Rushville, NY
This on-farm meeting will feature 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 such as inter-row cover crops, grafting and, where appropriate, spray options will be used to educate growers. Details on each topic will focus on field observations at the farm.
DEC recertification credits will be offered (1.75 credits in categories 10, 1a, 23, 24).
Vegetable Pest and Cultural Management Meeting for Auction Growers (FLPA)

July 12, 2023
Penn Yan, NY
This meeting will feature 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 such as inter-row cover crops, grafting and, where appropriate, spray options will be used to educate growers.
DEC recertification credits will be offered (1.75 credits in categories 10, 1a, 23, 24).
Vegetable Pest and Cultural Management Meeting for Auction Growers (Seneca)

August 2, 2023
Romulus, NY
This meeting will feature 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 such as inter-row cover crops, grafting and, where appropriate, spray options will be used to educate growers.
DEC recertification credits will be offered (1.75 credits in categories 10, 1a, 23, 24).