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ARS Home Northeast Area Beltsville, Maryland (BARC) Beltsville Agricultural Research Center Molecular Plant Pathology Laboratory People John Hartung





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**MPPL Home****Citrus Home****Canker****CVC****CTV****CYMV****Greening****Leprosis** **Greening Genes****Dodder****Greening & Seeds****Greening in plants****Citrus Facts****Collection** citrus pathogen logo Citrus Variegated Chlorosis Citrus Variegated Chlorosis or CVC is a disease of citrus caused by the xylem limited bacterial pathogen Xylella fastidiosa.  CVC is not present in the United States...yet.  The disease has caused considerable crop loss in Brazil and has also been found in Argentina.  Sweet oranges are more susceptible than grapefruit. image of a citrus tree with severe cvc infection leaves have a bright yellow mottlecvc symptom in grape also known as Pierce's disease  Xylella fastidiosa  CVC is spread by insects known as a sharpshooters or leafhoppers. The image of a sharpshootersharpshooters like to feed on a variety of plants, and the pathogen can also grow in a variety of plants, which is how the pathogen is spread from crop to crop.  phylogenetic tree showing cvc in citrus related to other cvc strains  image depicting feeding cycle of a sharpshooter moving from citrus to ornamental shrub The symptoms of CVC include a bright leaf mottle in citrus.  An infected citrus tree also produces fruit which are very small and because they contain very little juice they are very hard and can damage commercial juicing machinery  Fruit from cvc infected tree(photo courtesy R. Brlansky-UFL).  In the greenhouse we have observed if the plants are watered, fertilized and grown optimally the plants are healthy in appearance and symptomless. We do not grow our citrus plants large enough in our greenhouse to produce fruit.  Environmental stress may play a large role in symptom expression. Sharpshooters and Pierce's disease are found in Florida but so far no CVC disease has been found.  As with all other pathogens of citrus it will likely be introduced by someone carrying in budwood from an infected tree. orange line For more information about citrus pathogens please contact Dr. John Hartung For more information concerning growing citrus please contact Cristina Paul  Juicy links logo Florida Juice Commision* University of Florida* Sunkist kid's stuff* The Ultimate Citrus Page* California Citrus Research Board* Citrus from Down Under- Citrus Australia * Texas Citrus* * Goes to non-federal site


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