As communicated in the July 27, 2007 U.S. Official Pest Report, the Animal and Plant Health Inspection Service (APHIS) confirmed the detection of orange rust of sugarcane, Puccinia kuehnii, in commercial sugarcane fields in Palm Beach County, Florida. Since the initial detection in Palm Beach County, additional detections of orange rust have been confirmed in fields located in at least three other Florida counties: Hendry, Glades, and Martin.
A team of subject mater experts from APHIS, the Florida Department of Agriculture and Consumer Services Department of Plant Industry, and the sugarcane industry have assessed the situation. Based upon survey results indicating a widespread distribution of orange rust throughout the sugarcane growing areas in Florida and because this rust is an airborne disease, the team of subject matter experts have determined that regulatory action will be ineffective in preventing the spread of the disease. Accordingly, APHIS and State Regulatory Officials have decided that no regulatory actions will be taken. APHIS and Federal and State cooperators plan to support the sugarcane industry in the development of short-term and long-term control strategies, including the planting of resistant varieties of sugarcane.
The initial symptoms of orange rust are minute, elongated yellow lesions, which take on a pale yellow-green halo as they increase in size. As the lesions grow, an orange to orange-brown color develops. Unlike common brown rust, orange rust lesions are never dark brown. Pustules of orange rust tend to occur in groups on the affected leaf surface with most pustules on the lower surface and more lesions toward the leaf base. Wind and large air masses can rapidly spread the pathogen.
Under IPPC standards, the status of Puccinia kuehnii in the United States has changed from transient, actionable, and under surveillance to present, only in some areas.