A possible incursion of the glassy-winged sharpshooter, an American leafhopper, and a pathogen it carries is likely to have severe and widespread impacts on citrus and wine and table grapes in Australia.A possible incursion of the glassy-winged sharpshooter, an American leafhopper, and a pathogen it carries is likely to have severe and widespread impacts on citrus and wine and table grapes in Australia.

Industry and Investment NSW researchers studying the pest insect believe it is highly likely it will reach Australia in the near future and there is a chance the bacterial pathogen which causes disease such as Pierces disease, Xylella fastidiosa, may already be here undetected.

"Climates in much of coastal Australia, particularly eastern and southern regions, suit the insect and the pathogen," said Leigh Pilkington, Industry and Investment NSW research scientist at the Gosford Primary Industries Institute.

"The southeastern American and northeastern Mexican native sharpshooter and pathogen are both highly mobile and have expanded their range through the South Pacific.

"People often inadvertently import the insect as eggs on the underside of leaves on nursery stock, while the pathogen arrives as symptomless infections within plants.

"The pathogen also causes a range of diseases in other important crop species including almond, coffee, plum, pear and avocado."

Dr Pilkington and Charles Sturt University PhD student, Anna Rathe, are conducting research supported by the Cooperative Research Centre for National Plant Biosecurity to help detect any incursion in Australia early, predict the behaviour of the pest and pathogen prior to their arrival and minimise their impact.

"Symptoms exhibited by infected plants tend to mimic those of water stress, such as leaf scald, necrosis and underdeveloped fruit," Dr Pilkington said.

"The diseases caused by the pathogen have no cure - the only available course of action is to halt the spread of the pathogen by managing the insect.

"We have examined a range of Australian native plants exposed to a high level of pest and pathogen pressure in California, where in just two years around $100 million damage was caused to grapes and ornamental plantings in Riverside and San Diego counties.

"There will also be ongoing surveys in Australia for the pathogen to reveal any current symptomless pathogen infections that might exist."

Further reading

Glassy-Winged Sharpshooter (www.invasivespeciesinfo.gov)

Media contact: Tom Braz 0428 256 596