Citrus canker was recently confirmed for the first time in southern Santa Rosa County in the Florida Panhandle.
Citrus canker has been a major pest of citrus in south and central Florida. It is economically damaging to the commercial industry and is problematic to homeowners because it causes premature fruit drop, discolored fruit and eventually causes the tree to become unproductive.
Caused by the bacterial pathogen Xanthomonas citri subsp. citri., the canker was first discovered in 1912 in Florida and was declared eradicated in 1933.
The disease was found again in the Tampa area on citrus in 1986. It was declared eradicated in 1994, but again was found in 1995 in Miami.
This time, the disease was not successfully eradicated in part because hurricanes made the disease too widespread to control.
Despite its prevalence in south and central Florida, this disease has not been known in the Panhandle. The University of Florida and the Florida Department of Agriculture and Consumer Services’ Division of Plant Industry will assess the extent of the disease in Santa Rosa County in the coming months.
One of the best indicators of canker is lesions, or diseased spots, on the upper and lower surfaces of the leaves. The lesions will be raised and have a rough surface and will be surrounded by yellow halos. Similar lesions may be present on the fruit and stems as well.
Do not move a plant infected with citrus canker. Call the local Extension office for help.
The disease is highly contagious to citrus only and spreads rapidly through wind, rain and by people. Do not transport any plant material that shows symptoms of canker.
Decontamination practices should be used when going from one citrus tree to the next.
Wash hands with soap and water for 20 seconds or more to eliminate bacterium as well as using alcohol-based hand sanitizers. Pruning tools or other tools that come into contact with citrus should be disinfected by a fresh solution of one ounce of household bleach to one gallon of water.
An old or dirty bleach solution is not able to disinfect because the chemical is no longer active.