This week the USDA announced the discovery of Citrus Black Spot, the latest major disease to become a destructive pest to the citrus crop of Florida. Major diseases currently present are tristeza, blight, greasy spot, Alternaria brown spot, Phytophthora- induced diseases, melanose, scab, postbloom fruit drop, citrus canker and Huanglongbing (citrus greening).
A commercial grove in Collier County was the location of the recent discovery of Citrus Black Spot, a fungal disease that causes dark speckled spots or blotches on the rinds of fruit. Valencia orange and lemon are the most susceptible varieties of citrus for this fungus.
Before coming to Florida this disease has been a significant production problem in Southeast Asia, Africa, South America and Australia. It is spread in nursery stock and in dead leaves in the groves, and can be controlled by using protective fungicide treatments and inspecting nursery stock.
For more information see the University of Florida EDIS publication #PP213.
