Research to repel Queensland fruit fly

Homegrown strategies from the Department of Primary Industries (DPI) may soon answer growers’ needs to manage Queensland fruit fly (QFF) and maintain market access to domestic and export markets.

DPI research horticulturist, Jenny Ekman, said new repellents, combined with ongoing orchard management and post-harvest measures, could contribute to a systems approach aimed at maintaining access to QFF-free markets.

"Early this year we ran trails in Bathurst using kaolin clay and light spray oil on apple and peach crops," Dr Ekman said.

"The results were impressive - clay treatments reduced the amount of QFF sting marks on apples by 92 per cent and most importantly, there were no larvae or maggots in the fruit.

"Spray oil was most effective when used on peaches, reducing larvae numbers in fruit by up to 63 per cent."

Dr Ekman said the conditions under which the trial ran, with torrential rain and severe weather conditions, impacted on the effectiveness of the treatments.

"This season we will be increasing applications and fine-tuning spray timing to determine the most effective way to use the products," she said.

"Neither treatment is yet registered for fruit fly control, but both treatments are registered on fruit crops.

"Internationally-recognised research has shown that kaolin clay, an organically registered product commonly used to prevent sunburn in apple production, can also repel QFF.

"Light spray oil emulsions are registered as an insecticide for a variety of horticultural crops, including citrus, banana, pome and stone fruit.

"Mainly used for aphids and mites, we have evidence that spray oils have effectively managed QFF in tomato crops.

"We already know that both treatments are soft on beneficial insects and would fit into an integrated pest management system."

QFF cause havoc in crops when females lay eggs in fruit – the eggs hatch into maggots which feed on and destroy the fruit. http://www.dpi.nsw.gov.au/agriculture/pests-weeds/insects/qff

View the YouTube video: Search for Queensland fruit fly repellents

Photographs are available from bernadette.york@dpi.nsw.gov.au

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