Citrus greening is one of the most serious diseases of citrus worldwide. Citrus greening is spread by the Asian citrus psyllid, Diaphorina citri, a recently introduced pest in Florida and Hawaii. There are three strains that are commonly associated with it. The Asian strain was found in Florida in 2005. This disease also has been referred to as Huanglongbing or yellow dragon disease.

There is no effective control for the disease other than removing infected trees. Infected trees cannot be cured. They generally die within three years of becoming infected. The bitter-tasting, misshapen and underdeveloped fruit is unmarketable.

Citrus trees may not show signs of infection for several years. The initial signs may be misidentified as a zinc deficiency or another disease. DNA analysis is the only definitive method of diagnosis.

For additional information regarding citrus greening, program and regulatory updates, and related links and online resources, go to:

USDA APHIS Plant Protection and Quarantine

Southern Plant Diagnostic Network