Research has investigated field-applied fungicides and postharvest treatments for the management of asparagus rust (caused by Puccinia asparagi) and phomopsis stem blight (caused by Phomopsis asparagi) of asparagus in Queensland. Field trials were carried in grower's properties at Mundubbera (trial 1) and Warwick (trial 2), Queensland. Fungicides were applied to asparagus fern approximately 4 weeks after spear emergence and then again at 8 weeks after emergence using a petroldriven spray tank,

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... hrough an adjustable hollow cone nozzle at a rate of approximately 5 litres/plot. Four weeks after the second fungicide application the percentage of plants with disease symptoms was estimated. In trial 1, the fungicides difenoconazole and propiconazole were shown to reduce the incidence of asparagus rust. Difenoconazole and carbendazim reduced the severity of phomopsis stem blight in trial 2. In preliminary experiments some postharvest disinfestants (a mixture of chlorine + bromine, chlorine dioxide, peroxyacetic acid, sodium hypochlorite and chlorine) were highly effective at reducing pathogen spore germination in vitro. Integrated strategies based on field management and postharvest disinfection methods are suggested for use should these diseases spread to New Zealand.