Bacterial leaf scorch on blueberry was reported for the first time in Kentucky in October 2015. This disease is common within the southeastern states, including Georgia, Alabama, and Mississippi. While little is known about the disease, insect management is critical for preventing spread. Once infected, plants often die within one to two growing seasons. There is no cure for bacterial leaf scorch.
Bacterial Leaf Scorch of Blueberry Facts
- Infected plants exhibit browning at the margins of leaves, and often a dark band develops between diseased and healthy tissue (Figure 1).
- Defoliation occurs and stems/twigs may appear yellow in color (Figure 2).
- Symptoms of bacterial leaf scorch can resemble abiotic/stress, so confirmation by a diagnostic lab is advised.
- Caused by the bacterium Xylella fastidiosa subsp multiplex. The same subspecies is also known to infect oak and other common landscape trees (Figure 3).
- Transmitted by leafhopper and treehopper insects.
- Highbush blueberry varieties are susceptible to bacterial leaf scorch.
There is no cure for bacterial leaf scorch, and blueberry plants will eventually die once infected. The following suggestions may help reduce the spread of the disease:
- Remove and burn, bury, or dispose of infected plants immediately
- Avoid propagating potentially infected blueberry plants
- Reduce plant stress and maintain plant vigor
- Manage insect vectors
- Plant Pathology Extension Publications (University of Kentucky)
- Bacterial Leaf Scorch of Blueberry (University of Georgia)
- Statement of EFSA on host plants, entry and spread pathways and risk reduction options for Xylella fastidiosa, Wells et al. (European Food Safety Authority Journal 2013
By Kimberly Leonberger, Extension Associate, and Nicole Ward Gauthier, Extension Plant Pathologist