25 June 2021
|Biosecurity Advice 2021-P10 - Final group pest risk analysis for soft and hard scale insects on fresh fruit, vegetable, cut flower and foliage imports PDF||2||187 KB|
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This Biosecurity Advice notifies stakeholders of the release of the Final group pest risk analysis for soft and hard scale insects on fresh fruit, vegetable, cut flower and foliage imports.
The final group pest risk analysis identifies 243 species of soft scale and 332 species of hard scale insects as quarantine pests for Australia.
The final group pest risk analysis recommends measures for scale insect quarantine pests, as well as alternative risk management options. These may be considered on a case-by-case basis when developing new import conditions for specific commodities or when reviewing existing import conditions for commodities that are currently traded.
The final group pest risk analysis considered all submissions received from stakeholders on the draft group pest risk analysis.
The Final group pest risk analysis for soft and hard scale insects on fresh fruit, vegetable, cut flower and foliage imports is the third group pest risk analysis (PRA) to be finalised. Group PRAs for thrips and orthotospoviruses, and for mealybugs and the viruses they transmit, were finalised in 2017 and 2019, respectively.
This group PRA considered the biosecurity risk posed by all members of the family Coccidae (soft scales) and the family Diaspididae (hard scales or armoured scales) in the insect order Hemiptera. There are more than 3,900 described species of scale insects. The group PRA also considered the potential for scale insects to act as vectors for plant viruses and whether these viruses are quarantine pests for Australia.
The group PRA identified 243 species of soft scales and 332 species of hard scales as quarantine pests for Australia. The pest risk assessment concluded that scale insect quarantine pests have an indicative unrestricted risk estimate (URE) of ‘Low’ which does not achieve the appropriate level of protection (ALOP) for Australia. This risk estimate is regarded as indicative because the likelihood of entry can be influenced by a range of pathway-specific factors (such as the commodity, seasonal considerations, the incidence of pests in specific export production areas, or host range), and must be verified on a case-by-case basis. In some cases, the likelihood of entry may need to be adjusted to take account of these factors.
This group PRA also assessed the potential for soft and hard scale insects to act as vectors of plant viruses. No species of hard scale was found to transmit plant viruses. Eight species of soft scales were identified as being able to transmit a total of 4 viruses associated with grapevines. However, these viruses are not quarantine pests because they are already present in Australia.
Phytosanitary measures are required for scale insect quarantine pests if the indicative unrestricted risk estimate of ‘Low’ is verified for a specific plant import pathway. Where measures are required, the following options are recommended:
- pre-export visual inspection and if quarantine scale insects are found, remedial action (e.g. suitable treatment) to manage the identified pest
- systems approach
- area freedom.
On-arrival verification will be undertaken to provide assurance that Australia's import conditions have been met. Imported goods that are frequently found to be infested with scale insects may be subject to mandatory pre-export treatment approved by Australia (e.g. methyl bromide fumigation).
The final report and more information about this risk analysis are available on our website. Printed copies of the report are available on request.
Dr Chris Parker
First Assistant Secretary
Biosecurity Plant Division
Telephone: 1800 900 090 (option 1, option 1)