|Brlansky, R. - UNIV. OF FLORIDA|
Submitted to: Plant Disease
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: June 18, 2002
Publication Date: November 1, 2002
Citation: BRLANSKY, R.H., DAMSTEEGT, V.D., HARTUNG, J.S. TRANSMISSION OF THE CITRUS VARIEGATED CHLOROSIS BACTERIUM, XYLELLA FASTIDIOSA, WITH THE FLORIDA SHARPSHOOTER, ONCOMETOPIA NIGRICANS WLAKER. PLANT DISEASE 86:1237-1239. 2002. Interpretive Summary: Citrus variegated chlorosis (CVC)is a very destructive disease of citrus in Brazil but has not been found in the U.S. Forms of this bacteria cause diseases of grapes, almonds, oaks, etc., in the U.S. The bacteria that cause the disease grows in the water-transporting tissue of the tree. The disease causing bacteria are moved from tree to tree by large, soft-bodied insects called sharpshooters. A sharpshooter common in the citrus growing area of Florida was tested and found to be a potential transmitter of this bacterium. Insects from Florida were brought to the Quarantine Facility in Fort Detrick, MD, and found to be capable of acquiring and transmitting the bacteria as single insects or groups of insects. The presence of potential vectors in the citrus- producing areas of Florida increases the threat of establishment and spread of CVC in the U.S. should it be introduced by some means.
Technical Abstract: Citrus variegated chlorosis (CVC) is an economically destructive disease in Brazil and is caused by the bacterium, Xylella fastidiosa. The bacterium has been found to be transmitted in Brazil by sharpshooter leafhoppers (Cicadellidae).Sharpshooters are present in most citrus- growing areas of the U.S. The sharpshooter leafhopper, Oncometopia nigricans Walker, frequently is found feeding on citrus in Florida. This sharpshooter transmits the X. fastidiosa strains that cause Pierce's disease of grapes and ragweed stunt. Research was initiated to determine if O. nigricans were capable of vectoring the X. fastidiosa that causes CVC. In 59 different transmission tests, using 1 to 57 insects per test, transmission of the bacterium was observed 12 times (20.3%). Symptom development in the greenhouse was not a reliable indicator of transmission. Transmission was verified by specific PCR-based assays. Individual insects were able to transmit the bacterium. This information on sharpshooter transmission of CVC is needed to assess the threat posed by the CVC disease to the citrus industries in the U.S.