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Late Blight Information

The purpose of this site is to provide updates on managing late blight of potato and tomato in New York and the contiguous states and Canadian provinces.

Reports of where late blight has been found in the U.S. can be found at:  Links to resources on late blight identification and management are also provided.

To contact Abby:

Management Information

If You Think You’ve Found Late Blight

It’s important not to ignore infected plants! Confirm whether you have late blight and determine an appropriate management plan. If you think you’ve found late blight, and especially if it’s the first sighting in your area, please go to the USAblight web site and click on “Reporting Outbreaks” on the top dark green ribbon. Click on “registration,” enter your email address, click on “Go”, and then enter your name and contact information on the next page. Once you’ve registered, read the “How do I sample?” and “Where do I submit a sample?” information, then fill out the sample submission form. If you fill it out online you will get a sample tracking number and an APHIS permit will be emailed to you that you must include in the package with your sample if you’re sending it across state lines. USDA funding is supporting late blight diagnosis and identification of pathogen strains, so there is no fee for submitting a sample. Once submitted, you can track your sample and find out if the late blight diagnosis was confirmed as well as the strain of the pathogen by clicking on “Track your Sample” and entering your email address.

Characteristics of Late Blight (Phytophthora infestans) Isolates

Late Blight Isolates

Handouts and Posters