Rust on Blueberries

Dr. Phil Brannen has found a small amount of rust on some blueberries. Read below for his comments.

Within the last few days, we have found at least one significant blueberry rust site in south Georgia. You might want to encourage your producers to scout for this disease at this time. The rust spores can be easily observed in spots on the underside of leaves, but in the early stages, the same spots on the upper leaf surface might possibly be confused with Septoria leaf spot or chemical damage. I have never personally observed rust this early in the season (normally found in late July or August), and this disease can defoliate plants, resulting in subsequent yield losses in the following year. Fungicides which are active against rust include chlorothalonil products (Bravo), DMI products (Indar, Orbit, Tilt), and strobilurin-containing products (Cabrio and Pristine); encourage producers to apply these according to the label, and rotation between classes of chemistry will help to prevent resistance development.

For more info on blueberry dieseases, check out UGA's publication here.