CONTROL OF ORANGE RUST IN SUGARCANE WITH FUNGICIDES

Orange rust, an important leaf disease, has caused significant yield losses of up to 40% in the highly susceptible variety Q124 over the past three years. The disease caused the greatest losses in the central and southern cane growing regions of Queensland. Fungicide experiments were conducted over a two-year period in the central district. Four fungicides were applied at six sites in varying combinations and schedules to provide a range of disease control strategies. Orange rust in susceptible varieties can be economically controlled if fungicide is applied when a high-yielding crop is expected, fungicide application occurs early in the infection cycle, a high percentage of the leaf area is affected, the correct fungicide is selected and sugar price is greater than $A300. The planting and cropping of resistant varieties will be the main disease control strategy for this disease.