Citrus canker, a fruit tree disease that appeared several years ago in the Houma-Thibodaux area, has been spreading in Louisiana. It was recently found in the East Baton Rouge and Livingston parishes.
Citrus canker is a highly contagious bacterial disease that was first detected around 1914 in Louisiana and declared eradicated by 1940. But the disease reappeared in the state in June 2013. It is known to cause defoliation, premature fruit drop, blemished fruit and tree decline. Severely infected trees ultimately may stop producing fruit.
Houmatoday.com quoted LSU AgCenter plant doctor Raj Singh as saying: “The pathogen produces raised, corky lesions on upper and lower surfaces of the leaves. Lesions on the upper surface are surrounded by a yellow halo, whereas older lesions on the lower surface tend to lose the yellow halo.”
The disease can spread rapidly in Louisiana’s hot and humid climate, he said. There are no effective treatments to eliminate the disease after the infection has occurred. The disease affects citrus only, and all citrus varieties are susceptible.
After the reappearance of the disease in the state in 2013, a quarantine zone was established. Federal and state quarantine regulations prohibit movement of citrus plants, any plant parts, clippings or fruit out of the quarantined zone.
The quarantine zone does not include East Baton Rouge and Livingston parishes. The affected plants have been removed from the two nurseries where the disease was found.