Currant Lettuce Aphid can cause major losses to lettuce crops by feeding within the heart of the vegetable.

A response and surveillance program is underway for an insect called Currant Lettuce Aphid following the detection of the pest at a site in the Sydney Basin.

NSW DPI Executive Director, Biosecurity, Compliance and Mine Safety, Doug Hocking, said routine surveillance by the NSW DPI led to the detection of the insect in what is the first positive detection of Currant Lettuce Aphid in NSW.

'Currant Lettuce Aphid poses no threat to human health,' Mr Hocking said.

'However it is a threat to the State’s $25 million lettuce industry, as it can cause major losses to lettuce crops by feeding within the heart of the vegetable.

'Movement controls on lettuce from the affected site are in place to ensure lettuce only moves from the property to areas where possible spread of the insect is limited.

'Current Lettuce Aphid has not been detected in any other lettuce production region in NSW.

'A management group consisting of representatives from NSW Farmers’ Association, the lettuce industry, seedling propagation industry, processing industry and the NSW DPI has been formed to develop a strategy to manage the pest.

'The insect already exists in Victoria and Tasmania where it has been accepted that eradication is not possible. As a result, control and surveillance measures are in place to minimise the impact on lettuce industries.

'Lettuce moving from Victoria into NSW has to meet strict conditions of entry. These include inspection and treatment.

'At this stage it is unknown how Currant Lettuce Aphid made it to the Sydney Basin property.

'However it is widely known that the insect can spread two ways – by wind and as hitchhikers on produce, vehicles and people.'

NSW Department of Primary Industries researchers had been preparing for the discovery of Currant Lettuce Aphid in NSW for sometime and already have research projects underway to develop practical control measures.

'We have been working with the lettuce industry since the detection of Currant Lettuce Aphid in Tasmania in 2003 to prepare for the inevitable spread of the pest to other growing areas,' Mr Hocking said.

'Trials involving insecticideo ptions as well as Integrated Pest Management (IPM) are being conducted at the NSW DPI’s National Vegetable Industry Centre at the Yanco Agricultural Institute.

'The researchers have trial sites in Tasmania and have revealed that lady beetles and brownlacewings can control lettuce aphids.

'Sydney growers have been part of some of the research work.

'The way the insect gets into the heart of the lettuce, especially head lettuce, makes chemical treatment difficult.

Therefore an arsenal of effective insects that can get to the centre of the lettuce and attack the aphid has been identified and is being trialled.

'The department is also planning to establish a number of demonstration sites across the State showing the effectiveness and virtues of IPM.'

This story appears in Agriculture Today.