A citrus tree at a private residence near San Diego, California, has been found to be infected by four Asian citrus psyllids (ACP). Upon testing, the ACP were found to be carriers of the bacterium that causes citrus greening, also known as huanglongbing (HLB).
The finding was announced by the California Department of Food and Agriculture’s Citrus Pest and Disease Prevention Program on Jan. 1.
According to the news release, an ACP sample – confirmed positive for Candidatus Liberibacter asiaticus (CLas), the bacterium that causes HLB – was collected from a residential property in the Fallbrook area. Confirmed by the Citrus Research Board’s Jerry Dimitman Laboratory, this adult psyllid sample is the first CLas-positive ACP found in San Diego County.
While the ACP find is concerning, HLB has not been detected yet in any San Diego County trees. Surveying and sampling of area trees is ongoing. This find signals a critical time for homeowners and growers alike to continue to control ACP populations to stop the potential spread of this deadly disease, as oftentimes a CLas-positive ACP precedes the detection of an HLB-positive tree.
The HLB quarantine zone will not be expanded as a result of this CLas-positive ACP detection. California Department of Food and Agriculture staff is swiftly conducting surveys and collecting samples from HLB host plants that are located within a 250-meter radius around the find, per the ACP/HLB Action Plan.
While treatment is not mandatory for area commercial growers as a result of the detection, San Diego County commercial growers who have additional questions can contact Sandra Zwaal, grower liaison, at szwaal2@gmail.com.
See more details on the CLas-positive ACP detection.
Source: Citrus Insider, California Department of Food and Agriculture