Official Pest Report

Official Pest Reports are provided by National Plant Protection Organizations within the NAPPO region. These Pest Reports are intended to comply with the International Plant Protection Convention's Standard on Pest Reporting, endorsed by the Interim Commission on Phytosanitary Measures in March 2002.

Detections of Ralstonia solanacearum race 3 biovar 2 in U.S. Greenhouses

Country: United States

Title: Detections of Ralstonia solanacearum race 3 biovar 2 in U.S. Greenhouses

Not available


APHIS has confirmation of Ralstonia solanacearum race 3 biovar 2 in geraniums in four commercial greenhouses in Illinois, Indiana and Wisconsin. All greenhouses received infected propagative material from the Goldsmith Plants, Inc. facilities located in Kenya. This is a bacterial pathogen that causes wilt in geraniums (Pelargonium), is highly destructive to potatoes, and infects numerous other solanaceous plants (e.g. tomatoes, eggplant, and chile peppers). Confirmation testing was done by the Plant Protection and Quarantine (PPQ) Center for Plant Health Science and Technology laboratory in Beltsville, Maryland.

Goldsmith voluntarily quarantined two greenhouses in Kenya in January 2003 and suspended shipments of geranium cuttings from those greenhouses for the remainder of this season. They have also alerted customers that may have received cuttings infected with Ralstonia. It appears that several hundred customers may be impacted, and PPQ is currently conducting trace forward activities to determine the location of the shipments in the United States. APHIS has implemented a prohibition for all geranium nursery stock from Kenya effective February 14. APHIS has sent officials to investigate the source production site for the infection.

R. solanacearum race 3 biovar 2 is cited on USDA's Agricultural Bioterrorism Act of 2002 Select Agents and Toxins list because it is a serious pathogen of potatoes that is not present in the United States. PPQ has no information that indicates the introduction of this pathogen was deliberate but instead resulted from unintentional contamination in the routine importation of geraniums.

Shipments from the affected greenhouses will be suspended until PPQ ascertains that tests for the presence of the pathogen are negative. Contaminated U.S. greenhouses will not be allowed to move plants until PPQ-approved procedures are used both to destroy plants and decontaminate greenhouses. PPQ is in the process of evaluating protocols to screen geraniums for R. solanacearum race 3 biovar 2, so more information will be forthcoming on this issue.

The Ralstonia detections and subsequent APHIS action will coincide with key shipping times for geraniums for both Kenyan interests and the domestic greenhouse industry. APHIS will make every effort to implement its emergency response as soon as technically feasible to ensure that U.S. potatoes and other solanaceous plants are safeguarded, and to minimize adverse impact on the geranium industry. 

For more information about Ralstonia see the following: 

Posted Date: Feb. 18, 2003, 9 a.m.