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Should you be concerned about Ralstonia solanacearum race 3 biovar 2?

What is Ralstonia solanacerum?
It is a bacterial pathogen that can cause injury to different plants, including tomato, potato, vegetables, and some ornamentals.

Occurrence: This pathogen is grouped into five different races and biovars because of the large number of plants that it can attack/damage and the different tests necessary to identify them. In the southeastern United States, including Florida, the R. solanacearum race 1 biovar 1 is common and occurs naturally. 

The R. solanacearum race 3 biovar 2 (RsR3b2) was detected in a small number geranium-growing greenhouses in the United States.  Although RsR3b2 can cause similar damage to some crops as race 1, it is more worrying as as quarantine pathogen. 

Concerns and sample reporting: Because RsR3b2 is on the USDA-APHIS-PPQ ‘select agent and pathogen’ list, we are concerned about its potential movement around the U.S. Therefore, suspect samples should be submitted for identification to help mitigate its spread. Check out the following USDA guidance on reporting samples that test positive to Ralstonia solanacearum

Further reading: For more details about the symptoms, distribution, and management of RsR3b2, please visit the official report page. Also, check out our UF entomology and Nematology EDIS publications to learn about Ralstonia solanacearum on Blueberry and Geranium.

Acknowledgement: The Featured image, showing symptoms caused by bacterial wilt disease on ‘Arcadia’ blueberry, is credited to Dr. Philip Harmon (UF/IFAS).