Wednesday, July 3, 2013

Late Blight Has Arrived

Over the past 2 weeks, late blight, caused by Phytophthora infestans, has been knocking on the doors of our state. Aided by the monsoon-like weather we’ve been experiencing the past few weeks, our unwelcome guest has finally managed to get inside and start to wreak havoc. Late blight was officially confirmed on tomatoes from Guilford County on July 2nd. Today we diagnosed late blight on a tomato sample from Wake County and on a sample of tomatoes and potatoes from Watauga County.

Late blight can be a devastating disease on tomatoes and potatoes. Without proper preventative measures, late blight can completely defoliate and destroy a crop within one to two weeks.

The first symptoms of late blight on tomato leaves are irregularly shaped,
water-soaked lesions. (Photo: K. Ivors)
More information about tomato late blight and how to control it can be found in this tomato late blight factsheet produced by Dr. Kelly Ivors and in our earlier blog post

More information on potato late blight and how to control it can be found in this potato late blight factsheet produced by Dr. Lina Quesada-Ocampo.


Videos and additional management recommendations for tomato and potato are available in the USAblight website. Here you can track the late blight epidemic and register to receive text and/or email alerts when new disease outbreaks are reported.