Citrus disease causing problem in some parishes

(10/04/16) BATON ROUGE, La. – Citrus canker, a highly contagious bacterial disease, is costing citrus growers their fruit and income in several parishes.

“The disease was first detected around 1914 in Louisiana and declared eradicated by 1940,”said LSU AgCenter “Plant Doctor” Raj Singh. “Citrus canker reappeared in the state in June of 2013.”

As a result, a quarantine zone was established in November 2013 to restrict the movement of citrus trees and other materials that might spread the disease.

Currently, the entire parishes of Orleans and St. Bernard and portions of Jefferson, St. Charles, Lafourche and Plaquemines parishes are quarantined for citrus canker.

About a month ago, the disease was found throughout Plaquemines Parish and in two locations in St. John the Baptist Parish.

“These new areas are in the process of being quarantined by the Louisiana Department of Agriculture and Forestry,” Singh said.

Federal and state quarantine regulations prevent the movement of citrus plants, any plant parts, clippings or fruit out of quarantined zone.

In addition, federal restrictions require that tools, equipment and personnel performing any service work on properties where a citrus tree is present must be disinfected with a bacterium-killing solution before leaving the property.

Citrus canker is a serious disease of citrus and directly threatens the survival of Louisiana’s citrus nursery stock and fruit industry. It causes defoliation, premature fruit drop, blemished fruit and tree decline. Severely infected trees ultimately may stop producing fruit.

Citrus canker may spread and develop rapidly in Louisiana’s favorable hot and humid climate, Singh said. No effective treatments can eliminate the disease after infection.

All citrus varieties are susceptible, although some varieties are less susceptible than others, Singh said.

Listed from the most susceptible to the least susceptible citrus fruits are: grapefruit, trifoliate oranges, Mexican or Key limes, navel oranges, sour oranges, sweet oranges, lemons, satsumas, tangerines, Mandarin oranges, king oranges and kumquats.

If you believe your citrus trees have citrus canker, contact the U.S. Department of Agriculture at 225-298-5410 or the Horticulture and Quarantine Division of the Louisiana Department of Agriculture and Forestry at 225-952-8100.

More information about citrus canker can be obtained by calling Singh at 225-578- 4562 or The Citrus Canker Factsheet LSU AgCenter Publication 3269 is available online at and typing “citrus canker” in the search box.

Meyer Lemon infected with Citrus Canker.JPG thumbnail

Meyer lemon fruit infected with citrus canker (Photo by Raj Singh, LSU AgCenter)

10/4/2016 7:38:17 PM
Rate This Article:

Have a question or comment about the information on this page?

Innovate . Educate . Improve Lives

The LSU AgCenter and the LSU College of Agriculture