THE EFFECT OF SOIL AND SEEDCANE APPLICATIONS OF TRlADlMEFON ON THE INCIDENCE OF SUGARCANE SMUT (USTILA

Different methods of applying triadimefon to sugarcane setts and to the soil at planting for the control of smut were tested in field trials. Immersing healthy setts in cold water containing 250 pglml triadimefon was beneficial when the setts were subsequently inoculated with smut before planting or grown under low levels of the disease, but was ineffective when smut was severe. Treating seedcane for two hours in hot water (50°C) containing 250 pg/ml triadimefon was more effective than a similar treatment in cold water when smut was. severe. The application of high rates of triadimefon to the soil at planting was beneficial under conditions of severe. smut. The fungicides furmecyclox and propiconazole were similar to triadimefon in efficacy in a test using inoculated seedcane. Benefits from applying fungicides at planting persisted into ratoon crops.