Citrus canker has been confirmed within a commercial citrus grove in Bulloch County, Georgia – the second county in Georgia where citrus canker has been identified during 2022. This bacterial disease, which is subject to USDA-APHIS quarantine regulations, is widespread within Florida, and has also been found previously in Louisiana (2014), Texas (2016), Alabama (2021), a South Carolina nursery (2022), and in Decatur County, Georgia earlier this year.
Leaves with potential citrus canker symptoms (Figure 1) were first identified in Bulloch County in early September 2022, and leaf samples were initially tested by personnel at the University of Georgia – Tifton Campus. Positive samples were then forwarded to USDA-APHIS for official confirmation of the presence of the citrus canker bacterium in the symptomatic plant tissue.
As federal guidelines require surveys to determine the extent of citrus canker establishment in the state, GDA and USDA-APHIS PPQ personnel have been conducting a survey for citrus canker infected trees in Decatur County, Georgia since June 2022. Based upon the most recent find, survey efforts will now be expanded to include areas of Bulloch County adjacent to the commercial grove where citrus canker was identified.
More information about citrus canker symptoms, spread, diagnosis, and testing can be found here.
Figure 1. Citrus canker lesions within leafminer mine on citrus leaf from Bulloch County, Georgia (Photo by Mirza Beg – University of Georgia).
Dr. Jonathan Oliver is an Assistant Professor and Extension Specialist in the Department of Plant Pathology at the University of Georgia. He has a 70% research, 25% extension, and 5% service appointment. Dr. Oliver started in his current position at the University of Georgia in mid-2017 as an extension fruit pathologist at the Coastal Plains Experiment Station in Tifton, Georgia. His responsibilities include research and extension activities focused on pathogen biology and disease management in fruit crops grown primarily in the southern part of Georgia, including blueberries, blackberries, citrus, and other emerging fruit crops. Dr. Oliver obtained a BS degree in Plant Pathology and Microbiology & Cell Science from the University of Florida in 2005, and a PhD in Plant Microbe Biology from Cornell University, New York State Agricultural Experiment Station in Geneva, NY in 2011. In addition, he has also been postdoctoral researcher at Kansas State University and Auburn University. At Auburn, he characterized the interactions between the emerging bacterial pathogen, Xylella fastidiosa, and its blueberry plant hosts. He currently serves as a Plant Pathology Section editor for the Southeast Regional Blueberry Integrated Management Guide.
