Update on citrus quarantine pests in the USA
- 'Candidatus Liberibacter asiaticus' (EPPO A1 List)
In the USA, 'Candidatus L. asiaticus' is currently found throughout Georgia, Florida, Puerto Rico, and the US Virgin Islands. It is also found in portions of the following states: Alabama, California, Louisiana, South Carolina, and Texas. Quarantined areas in California have recently been extended. It was recently reported from Arizona and Mississippi.
In Arizona 'Candidatus L. asiaticus' was detected during routine surveys in December 2024 in a residential citrus tree in Nogales (Santa Cruz county). Nogales is located close to the southern border with Mexico and over 280 km from any citrus production in Arizona. The local authorities consider that the sparse desert landscape between Nogales and any production citrus, limits the risk for spread to commercial citrus. Further surveys will be conducted in Santa Cruz county to determine the extent of the infestation and quarantine and mitigation measures that are appropriate for this situation.
In Mississippi, 'Candidatus L. asiaticus' was first detected in February 2025 in plant tissue samples collected from residential properties in Harrison County. Official measures are applied in the entire state.
The pest status of 'Candidatus Liberibacter asiaticus' in the USA is officially declared as: Present: not widely distributed and under official control.
- Diaphorina citri (Hemiptera: Psyllidae – EPPO A1 List)
This vector of 'Candidatus L. asiaticus' was reported in the USA in Arizona in 2017 and Nevada in 2019. Quarantine measures are now applied in the entire states of Alabama, Arizona, Georgia, Florida, Louisiana, Mississippi and Texas, as well as in portions of California, Nevada and South Carolina.
- Phyllosticta citricarpa (citrus black spot - EPPO A1 List)
In the USA P. citricarpa was first reported in 2010 in Florida (EPPO RS 2010/077). As of May 2024, the disease was confined to portions of seven counties in south-west Florida. Quarantine areas have been extended to additional sections in the following counties: Collier, Glades, Hendry, Lee, and Manatee.
The pest status of Phyllosticta citricarpa in the USA is officially declared as: Present: not widely distributed and under official control.
- Xanthomonas citri subsp. citri (EPPO A1 List)
In the USA citrus canker occurs in Florida (EPPO RS 2006/123), Louisiana (EPPO RS 2013/171), Texas (RS 2017/028), Alabama (RS 2021/146), as well as in a commercial citrus grove Decatur county in Georgia and in a nursery South Carolina in 2022 (RS 2022/096). According to the USDA-Aphis website as of March 2025, citrus canker occurs throughout Florida and in limited areas of Alabama, Louisiana, and Texas.
The pest status of Xanthomonas citri pv. citri in the USA is officially declared as: Present: not widely distributed and under official control.
Sources
Arizona department of Agriculture (2025-01-28) https://agriculture.az.gov/news/press-release-citrus-greening-disease-detection-nogales-az-01282025
NAPPO Pest Alert System Official Pest Reports - USA
- 2024-05-17: Phyllosticta citricarpa (Citrus Black Spot): APHIS updates the quarantine areas in Florida
-2025-02-24: APHIS establishes a citrus greening (Huanglongbing) quarantine in Mississippi
- 2025-03-14: APHIS expands the citrus greening (Huanglongbing) quarantined area in California https://www.pestalerts.org/nappo/official-pest-reports/1136/
USDA-APHIS Citrus Diseases
https://www.aphis.usda.gov/plant-pests-diseases/citrus-diseases
Interactive map of regulated areas for quarantine pests of citrus https://www.aphis.usda.gov/plant-pests-diseases/citrus-diseases/citrus-quarantine-map