Disease puts citrus industry on alert

Date: 28/11/2002

The Australian citrus industry is under serious threat from a crippling plant disease, warns a leading entomologist, Associate Professor Andrew Beattie, from the University of Western Sydney.

Sweeping across the entire Indonesia archipelago including East Timor and Papua New Guinea, 'Yellow Dragon Disease', ('Huanglongbing' - formerly called Citrus Greening), retards citrus production and severely shortens the average age of citrus trees.

Professor Beattie says the chances of Yellow Dragon Disease invading Australia is extremely high and currently the Australian citrus industry is unprepared for the risk.

"Yellow Dragon Disease has been confirmed in the northern Indonesia/Papua New Guinea border at Jayapura in Irian Jaya," Professor Beattie says.

"The proximity to Australia means this is one of the most serious threats to the sustainability of the Australian citrus industry we've ever seen.

"This disease is responsible for the drastic retardation of commercial citrus production across Asia, as trees on average fail to survive more than five years.

"There's no cure for the bacterial disease and it can only be eradicated by destroying infected trees and then replacing them," he explains.

"The bacterium that causes the disease, liberobacter asiaticum, is transmitted by the Asian citrus psyllid (jumping plant lice). Citrus cuttings or bud wood also transmit the disease.

"Eradication would be costly and the disease could have horrendous ramifications on the citrus industry because disease-free countries could ban Australian citrus imports if our citrus became infected."

According to Professor Beattie, Queensland and the major production areas of South Australia and Victoria are at risk due to climatic conditions which would allow the disease to flourish. Queensland faces the greatest threat, where production in 2000/2001 was worth $125 million with exports of $22 million, primarily to Asia.

"The entire Queensland citrus industry could be gravely affected should the disease become established," Professor Beattie says.

In a pre-emptive response to the possible invasion of Yellow Dragon Disease, Professor Beattie and his research team, including Dr Paul Holford from UWS and CSIRO entomologist Dr Paul De Barro, are examining the potential impact of the disease in Australia and possible measures to protect citrus crops through the application of mineral and plant oils and integrated pest management.

"Yellow Dragon Disease or the Asian citrus psyllid has not reached Australia yet, so it is critical that we act now to prevent it.

"We're anticipating a big fight on our hands to save the industry from this disease. Our research aims to identify the best management strategies to prevent Yellow Dragon Disease taking hold in Australia and also methods to control it throughout Asia."

This research is part of a $3 million project 'Huanglongbing Management in Indonesia, Vietnam and Australasia', funded by the Australian Centre for International Agricultural Research, Horticulture Australia, UWS, the French Centre of International Cooperation and Agronomic Research, Gadjah Mada University in Indonesia, the Southern Fruit Research Institute and National Institute of Plant Protection in Vietnam.


For more information or requests for interviews contact Suzie Vlaming, Senior Media Officer, 02 9852 5823, 0414 308 701, s.vlaming@uws.edu.au