There is a new threat Florida blueberry growers should be wary of: bacterial wilt. In a memo sent to members of the Florida Blueberry Growers Association, President Dudley Calfee strongly advised growers to scout fields thoroughly for this “new and dangerous pathogen.”
The disease has initially been confirmed on three farms, two in Desoto County and one in Lake County. On all three farms, the variety ‘Arcadia’ was the most severely affected, according to Phil Harmon, UF/IFAS Plant Pathologist. Other varieties also may be susceptible, but additional research is needed before we will know for sure.
The following disease specs are courtesy of Harmon:
Plants with bacterial wilt will show signs of water stress such as wilting and marginal leaf burn. Symptoms can quickly become severe and can kill plants in as little as three weeks in inoculation trials. Plants also may be prone to develop severe symptoms of other stress diseases such as stem blight in the affected patches and may show symptoms of both diseases.
Crowns of blueberry plants with bacterial wilt have a mottled discoloration or light brown to silvery purple blotches with ill-defined borders. This discoloration is distinct from that which occurs with stem blight disease, because stem blight discoloration is typically pie-piece-shaped and pecan brown in color. Additionally, wood chips floated in water from crowns of plants with bacterial wilt will stream bacterial ooze. Stem blight infected wood chips do not.
