EFFICACY OF NEW CHEMICALS TO CONTROL PINEAPPLE SETT ROT OF SUGARCANE

PINEAPPLE SETT ROT, caused by Ceratocystis paradoxa, is an economically important disease of sugarcane worldwide. It causes germination failures of seedcane or setts leading to poor crop establishment. Among the registered fungicides in Australia, the organomercury fungicide Shirtan® (methoxy ethyl mercuric chloride) is the most popular because it may stimulate germination of setts in addition to controlling pineapple sett rot. However, the organomercury fungicides have greater health and environmental impacts than other fungicides in use due to the presence of mercury. Two glasshouse experiments and a field experiment were undertaken at Sugar Research Australia, Woodford, aiming to assess the efficacy of fungicides Vibrance®, Dynasty® and Mirador® against pineapple sett rot of sugarcane compared to two registered chemicals, Sinker® and Shirtan®, and to assess their ability to stimulate sett germination. The results of these experiments clearly indicate that Dynasty® and Vibrance® can be effectively used to control pineapple sett rot of sugarcane in glasshouse conditions with similar effectiveness to Sinker® and either better or similar effectiveness to Shirtan®. More research is needed to further evaluate the efficacy of fludioxonil (one of the component chemicals of Dynasty®) and Vibrance® in controlling pineapple sett rot under field conditions, and for the control of other important fungal diseases such as sugarcane smut.