Linda F. Benedict, Morgan, Johnny W.
The citrus canker disease has been detected in New Orleans by the U.S. Department of Agriculture’s Animal and Plant Health Inspection Service, Plant Protection and Quarantine division, according to LSU AgCenter plant scientist Raj Singh.
“It is a serious disease of citrus because it causes defoliation, premature fruit drop, blemished fruits and tree decline, and ultimately, the infected tree stops producing fruit,” Singh said.
Symptoms on leaves start as tiny raised blisters that may enlarge and become tan to brown as the disease develops.
“Lesions are visible on both sides of the leaves with water-soaked margins surrounded by a yellow halo,” Singh said. “As the lesion ages, the center becomes raised and corky and may fall out, giving it a shot- hole appearance.”
Citrus canker is a highly contagious disease, and all citrus – oranges, grapefruit, lemons, limes and satsumas – are susceptible but at different levels. The fruit infected with the disease is safe to eat but is too unsightly to be sold.
If people suspect this disease on a citrus tree, they are not to take samples from the tree, Singh said. Instead, they are to take a digital photo and send it to their local AgCenter office. AgCenter agents will then analyze the photo and report the incident to the USDA. Someone may follow up with a site visit.
(This article was published in the spring 2013 issue of Louisiana Agriculture magazine.)
The LSU AgCenter and the LSU College of Agriculture