Research at Cornell University has uncovered a new apple disease.  Paecilomyces rot is caused by infection by the Paecilomyces niveus mold.  While it looks similar to other postharvest apple diseases (like blue rot, apple ring rot, bull’s-eye rot, black rot and bitter rot) and produces the same harmful patulin toxin, Paecilomyces rot is unique and especially pervasive for the fact it can survive high temperatures.  Therefore, human exposure to patulin can occur even from pasteurized apple products - like juices and syrups - made from Paecilomyces niveus-infected apples.

Paecilomyces rot expresses itself through brown lesions at least 1.5 inches in diameter, similar to other diseases.  However, it does have some distinguising features as Dr. Megan Biango-Daniels, who discovered the disease, describes.  "For one thing, it kind of looks like a deep bruise, and on the surface, and especially with yellow or lighter-skinned apples, you can see distinct rings inside the circular lesion."  The brown lesions are also firm rather than soft and the infected tissue is not easily separated from the rest of the apple.

At this point, no definitive test exists to identify Paecilomyces rot.  Growers instead are encouraged to ask extension agents to culture soil samples to check for the mold's spores.  "It does look quite different from similar molds when you grow it in the lab," says Biango-Daniels.

Croptracker users can now find Paecilomyces rot in the software system's disease and pest archive.  


If disease - like Paecilomyces rot - is found in a bin or lot, Croptracker can trace it back to the originating block so growers can isolate the affected trees and address the problem sooner.  Need a refresher on any of Croptracker's features? Head over to our Knowledge Base, where you'll find step-by-step tutorials as well as common troubleshooting tips and more.  And as always, if you're ever stuck, never hesitate to e-mail us at or Live Chat with us by clicking the green speech bubble helpicon in your bottom right-hand corner.  We're always happy to help you let Croptracker make your farm become more efficient, safe, and profitable!



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NZ's Largest Apple Exporter Implements Croptracker