An official website of the United States government.

The .gov means it’s official.
Federal government websites always use a .gov or .mil domain. Before sharing sensitive information online, make sure you’re on a .gov or .mil site by inspecting your browser’s address (or “location”) bar.

This site is also protected by an SSL (Secure Sockets Layer) certificate that’s been signed by the U.S. government. The https:// means all transmitted data is encrypted — in other words, any information or browsing history that you provide is transmitted securely.

Citrus Greening

View all resources
Citrus greening
Citrus greening symptoms (brown necrotic or aborted seeds in infected mandarin) - Photo by J.M. Bové; INRA Centre de Recherches de Bordeaux, France
Scientific Name: 
Candidatus Liberibacter asiaticus
Common Name: 
Citrus greening, Huanglongbing (HLB), yellow shoot disease, yellow dragon disease
Native To: 
Date of U.S. Introduction: 
The vector, Diaphorina citri, was first discovered in Florida in 1998; the disease was first discovered in Florida in 2005; Louisiana in 2008; South Carolina and Georgia in 2009; California and Texas in 2012 (Michaud 2004; Wang and Trivedi 2013)
Means of Introduction: 
Possibly through illegally imported plant material (Michaud 2004)
Impact: 
Bacterial disease that infects citrus trees, where it shortens the lifespan of trees and reduces fruit yield and quality (Wang and Trivedi 2013)

Spotlights

USDA. Agricultural Research Service.

Dogs specially trained by Agricultural Research Service (ARS) scientists have proven to be the most efficient way to detect huanglongbing—also known as citrus greening—according to a paper just published in the Proceedings of the National Academy of Sciences. Currently, the only solid hope of curtailing the spread of citrus greening is to eliminate trees with the disease as quickly as possible to prevent further spread. Early detection of the citrus greening pathogen is crucial because trees can be infected and act as a source to spread the disease months or years before showing symptoms that are detectable by the naked eye. ARS plant epidemiologist Timothy R. Gottwald with the U.S. Horticultural Research Laboratory in Fort Pierce, Florida, discovered that dogs can be trained to sniff out the presence of Candidatus Liberibacter asiaticus, the bacteria that causes citrus greening, with greater than 99 percent accuracy.

USDA. ARS. Tellus.

A unique program run by the Agricultural Research Service in Fort Pierce, FL, uses specially trained dogs to detect citrus greening in orchards. The canine-detection method has an accuracy rate of 99 percent.

USDA. ARS. Tellus.

Agricultural Research Service (ARS) researchers in Florida have developed “attract-and-kill” traps to control Asian citrus psyllids in the suburbs where citrus trees are popular landscape plantings.

Texas A&M University. AgriLife Extension Service.

USDA NIFA research investment in Texas A&M AgriLife leads to breakthrough in fighting agricultural plant diseases. Researchers have made a discovery that will help combat fastidious pathogens, which cost U.S. agriculture alone billions of dollars annually.

U.S. Department of Agriculture.

The U.S. Department of Agriculture's (USDA) National Institute of Food and Agriculture (NIFA) today announced four grants totaling more than $13.6 million to combat a scourge on the nation's citrus industry, citrus greening disease, aka Huanglongbing. The funding is made possible through NIFA's Specialty Crop Research Initiative (SCRI) Citrus Disease Research and Extension Program, authorized by the 2014 Farm Bill.

U.S. Department of Agriculture.

USDA established a unified emergency response framework to address Huanglongbing (HLB), a serious disease of citrus that affects several U.S. states and territories. This framework will allow USDA and its many partners to better coordinate HLB resources, share information and develop operational strategies to maximize effectiveness.

Distribution / Maps / Survey Status

USDA. APHIS. Cooperative Agricultural Pest Survey. National Agricultural Pest Information System.

Quarantine

Florida Department of Agriculture and Consumer Services.

Federally Regulated

USDA. APHIS. Plant Protection and Quarantine.

Contains the legal description of current federal quarantine areas for several citrus pests and diseases. Users can search by state and pest to determine the quarantine area(s) by state. An interactive map of quarantine areas is also available.

USDA. APHIS. Plant Protection and Quarantine.

Contains the requirements for moving fruit, nursery stock, or other regulated articles for several citrus pests and diseases.

U.S. Government Printing Office. Electronic Code of Federal Regulations.

USDA. APHIS. Plant Protection and Quarantine.

A Federal Order is a legal document issued in response to an emergency when the Administrator of APHIS considers it necessary to take regulatory action to protect agriculture or prevent the entry and establishment into the United States of a pest or disease. Federal Orders are effective immediately and contain the specific regulatory requirements.

USDA. Animal and Plant Health Inspection Service.

See what states have a federal quarantine for any of the targeted Hungry Pests, and identify which pests or diseases are at greatest risk due to a suitable habitat. In addition to federal quarantines, state-level quarantines might apply see State Summaries of Plant Protection Laws and Regulations (National Plant Board).

Images

University of Georgia. Center for Invasive Species and Ecosystem Health.

Videos

Google. YouTube; Texas A&M University. Texas AgriLife Extension Service.

Selected Resources

The section below contains highly relevant resources for this species, organized by source. Or, to display all related content view all resources for Citrus Greening.

Partnership

USDA. APHIS. PPQ. CPHST. Identification Technology Program.

See also: Citrus Resource

Citrus Greening Solutions.
European and Mediterranean Plant Protection Organization.

National Plant Diagnostic Network.

You can become a more effective First Detector by familiarizing yourself with invasive target pests and pathogens known to exist in the U.S. If you think you have encountered one of the species or disease complexes listed, report its presence.

Texas Citrus Pest and Disease Management Corporation.
Federal Government

USDA. Agricultural Research Service.

USDA. Animal and Plant Health Inspection Service.

USDA. APHIS. Plant Protection and Quarantine.

International Government

Secretariat of the Pacific Community. Plant Protection Service.

See also: Pest Advisory Leaflets for more resources

Business Queensland (Australia).

State and Local Government
California Department of Food and Agriculture. Plant Health Division.
California Department of Food and Agriculture. Citrus Pest and Disease Prevention Program.
The Citrus Pest & Disease Prevention Program is an initiative funded by California citrus growers and administered by the California Department of Food and Agriculture dedicated to combating serious pests and diseases that threaten the state's citrus trees.

Florida Department of Agriculture and Consumer Services. Plant Industry.

Academic

University of California. Agriculture and Natural Resources.

ANR Publication 8218

University of California. Agriculture and Natural Resources.
Provides information to both growers and home gardeners, in two distinct sub-sites -- to get the basics on the insect and the disease it can vector, how to inspect your trees, how to treat your tree if you find ACP, critical things to do to help contain the insect population and deal with Huanglongbing (HLB), as well as additional information more specific to California.
Louisiana State University. AgCenter Research and Extension.
See also: Plant Diagnostic Center - Publications for more resources
University of Florida. Institute of Food and Agricultural Sciences Extension.
Electronic Data Information Source - publication resources

University of California - Riverside. Center for Invasive Species Research.

University of California. Statewide Integrated Pest Management Program.
See also: Pest Notes are peer-reviewed scientific publications about specific pests or pest management topics, directed at California's home and landscape audiences.
University of Florida. IFAS. Citrus Research and Education Center.
University of Minnesota.
University of Minnesota's electronic textbook of Integrated Pest Management, Radcliffe's IPM World Textbook, features contributed chapters by internationally recognized experts.
Professional

Citations