Australian olive growers are stepping up preparations against the risk posed by the bacterium Xylella fastisiosa after its spread was confirmed in China.
“At the beginning of this year, the Australian government noticed a scientific paper reporting Xylella had been found in walnuts in China,” Michael Southan, the chief executive of the Australian Olive Association (AOA), told Olive Oil Times.
“As a result, they conducted further investigations and confirmed that Xylella is indeed present there,” he added.
The AOA notified its members that China had been officially regarded as a high-risk country for Xylella fastisiosa.
In response to the new situation, imported nursery stock from China that could potentially host Xylella fastidiosa will now undergo increased testing, treatment and pre-export certification.
“This means much stricter precautions around plant material entering Australia,” Southan said. “It’s now significantly harder to import plant material from China if identified as a significant or high-priority host for Xylella fastidiosa.”
Additionally, Australian authorities announced emergency measures to regulate host nursery stock at the genus level rather than the broader plant family level.
This update allows for more targeted inspections. Previously, controls were applied to all plants within an entire botanical family, including species not genuinely at risk.
Shifting to genus-level regulation enables inspections to focus exclusively on plants truly at risk.
Further measures implemented by local authorities will include revisions to trade permits.
According to Australia’s Department of Agriculture, Fisheries and Forestry (DAFF), Xylella fastidiosa “is Australia’s highest national priority plant pest. It’s an invasive bacterial pathogen causing devastating diseases in over 700 plant species.”
In a note, DAFF emphasized that “if Xylella fastidiosa were to enter Australia, eradication would be virtually impossible, as no treatment or cure exists.”
A team from Xinjiang Agricultural University in Urumqi conducted the research, which confirmed the presence of Xylella fastidiosa in several walnut tree leaves.
The scientists identified the multiplex subspecies of Xylella fastidiosa, which is considered low-risk for olive trees.
However, they did not exclude the presence of other subspecies, indicating a potential risk for various other plant species, including olives. More