Citrus greening, also known as yellow shoot disease or huanglongbing, is one of the most devastating diseases of citrus worldwide.
In the United States, citrus greening was positively identified first in south Florida in 2005. It appeared for the first time in Louisiana during 2008 in the Algiers neighborhood of New Orleans. Since that time, however, no new Louisiana cases were reported until recently. During March 2014 and 2016, the disease was again confirmed from several citrus varieties at multiple properties in the Gentilly area of New Orleans.
Citrus greening is a bacterial disease, and the bacterium resides in the phloem (food conducting tissues) of the tree. Three strains of citrus greening bacteria can cause the disease. The Asiatic form (Candidatus Liberibacter asiaticus) is the most widespread, while the African form (Candidatus Liberibacter africanus) is present in Africa and the Middle East. The American form (Candidatus Liberibacter americanus) so far is found only in Brazil.
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The LSU AgCenter and the LSU College of Agriculture