Proposal to remove Grapevine pinot gris virus as a declared pest under Section 4 of the Plant Health Act 2009

June 30, 2021September 24, 2021

Purpose
To brief industry on the proposal to remove Grapevine Pinot Gris virus (GPGV) as a declared pest under Section 4 of the Plant Health Act 2009 in South Australia.

Summary
Grapevine Pinot Gris virus (GPGV) was gazetted as a declared pest under Section 4 of the Plant Health Act 2009 on 9 February 2017 by the Department of Primary Industries and Regions (PIRSA) as a means to manage response activities, following the detection of GPGV in New South Wales and then shortly thereafter in South Australia. These detections initiated a response under the Emergency Plant Pest Response Deed (EPPRD).

In early 2018, the Consultative Committee on Emergency Plant Pests (CCEPP), in consultation with industry, deemed that GPGV was not technically feasible to eradicate, and the virus was declared as established and present in New South Wales, South Australia and Victoria.

PIRSA no longer has grounds to continue to regulate grapevine material carrying this virus at the state border, given that:

South Australia cannot prove freedom from GPGV as testing indicates infection is relatively widespread;
GPGV was deemed not technically feasible to eradicate in Australia; and
GPGV is no longer regulated at the Australian border or any other state or territory borders.

Since 2018, GPGV, like other endemic grapevine viruses (e.g., Grapevine leafroll-associated viruses (GRLaV-1, GRLaV-3) and Grapevine virus A (GVA)), must now be managed by industry. This includes:

The propagation sector (nurseries and vine improvement associations) incorporating GPGV into their routine virus testing screen.
The South Australian Vine Improvement Association (SAVIA) in its endeavour to produce high health stock, actively managing the exclusion of GPGV from its source material, as with other endemic viruses.
Vineyard Owners, when top-working, including GPGV in their virus-testing suite.
Vineyard Owners requesting documented health status of planting material from nurseries and vine improvement associations prior to purchase.

Vinehealth is seeking industry feedback by 30 July 2021 on this proposal to remove GPGV as a declared pest under the SA Plant Health Act 2009.

Background
GPGV was first detected in New South Wales in late 2016, which initiated the Consultative Committee on Emergency Plant Pests (CCEPP – a committee established under the EPPRD), to determine if GPGV should be categorised as an Emergency Plant Pest and technically feasible to eradicate. Shortly after this initial detection, GPGV was also detected in South Australia.

At the time of detection in Australia, GPGV was a relatively new to science virus, first described internationally in 2012.

Routine screening for GPGV began in 2014 at post-entry quarantine, and then in 2015 at commercial laboratories – Crop Health Services (CHS), Agriculture Victoria and Waite Diagnostics, now part of the Australian Wine Research Institute (AWRI) Commercial Services.

On 9 February 2017, GPGV was gazetted as a declared pest under Section 4 of the Plant Health Act 2009 by PIRSA in response to the detections in New South Wales and South Australia, and pending surveillance to determine prevalence through the grapevine propagation sector and in commercial vineyards in Australia.

Targeted and general surveillance undertaken from 2017, demonstrated that GPGV is present in South Australia, Victoria and New South Wales in a range of locations and in multiple wine and table grape varieties. GPGV continues to be detected in commercial vineyard samples and in samples from the propagation sector sent to the two main diagnostic laboratories in Australia (CHS and AWRI).

In early 2018, the CCEPP in consultation with industry, deemed that GPGV was not technically feasible to eradicate and the virus was declared as established and present in New South Wales, South Australia and Victoria.

Given this, imported grapevine material positive to GPGV at the Australian border was no longer prohibited entry.

Since 2018, the propagation sector and broader industry has been responsible for managing GPGV. In particular, work to integrate the virus into Standards that govern the production of high-health status planting material and developing best practice management guidelines for grapevines infected with GPGV has been important. This management approach for GPGV is analogous to how the industry currently manages other endemic grapevine viruses such as GRLaV-1, GRLaV-3 and GVA.

Discussion
It is proposed that GPGV be revoked as a declared pest under the Plant Health Act 2009 given that it is categorised as established in South Australian vineyards, with industry now responsible for managing the presence and impact of GPGV through the propagation supply chain and best practice management of vineyards.

To what level has GPGV been detected at our commercial virus testing laboratories?
According to diagnostic testing performed at both the AWRI Commercial Services and CHS Agriculture Victoria on over 4,000 commercial vineyard and grapevine propagation sector samples submitted over the period between April 2018 to May 2021, 10% of all grapevine samples sourced from South Australia and 30% of all grapevine samples sourced from outside South Australia tested positive to GPGV. These positives occurred across a range of winegrape and table grape varieties as well as rootstocks.

We note that:

These testing results only pertain to a sub-sample of vines planted or propagated, rather than the entire population. The actual level of GPGV infection in commercial vineyards and the propagation sector is unknown, without significant traceability and modelling efforts on all positive samples sent for diagnostics post 2018. For commercial vineyards, the actual GPGV infection level could be lower in the general population than that reported above, given that often vines demonstrating some health issues are those preferentially sent for virus testing. On the other hand, the asymptomatic presentation of the virus in many varieties contributes to the difficulty in recognising potential infection in the field and therefore actual levels of infection in the general population could plausibly be higher than that detected through active testing.
For the propagation sector, these results reflect levels of infection at a point in time in the propagation process. They do not reflect movement of scion and rootstock material between states as part of the production supply chain and therefore the state in which the final material is planted.

With the current level of detection of GPGV in South Australia and interstate, breadth of infected varieties, and knowledge that interstate propagation material moves into South Australia routinely as part of the propagation material supply chain, the state is considered beyond a point at which eradication can be achieved. Consequently, South Australia cannot prove freedom from GPGV and therefore maintenance of GPGV as a regulated pest under Section 4 of the Plant Health Act 2009 is no longer warranted.

What does deregulating GPGV as a declared pest mean for industry in practice?
Once the South Australian Government Gazette is amended by PIRSA to remove GPGV as a declared pest under Section 4 of the Plant Health Act 2009, the following will apply:

The reporting to PIRSA of grapevine material suspected to be infected with GPGV will no longer be mandatory.
The reporting of positive detections of GPGV in South Australian grapevine material to PIRSA by commercial virus testing laboratories in Australia will no longer be mandatory.
Grapevine material (including propagation material and grapes) known to be infected with GPGV can no longer be prohibited by PIRSA from entering the state.
There will no longer be restrictions on the sale or supply in South Australia of grapevine material (including propagation material and grapes) known to be infected with GPGV.
Accountability by the propagation supply chain for minimising the presence of GPGV as part of production of high-health planting material should continue.
Accountability by the propagation supply chain and industry for best practice management of vineyards infected with GPGV should continue.

Does deregulating GPGV from the state border indicate that the level of risk to industry from GPGV is nil?
Given the recency of detection of GPGV in Australia, the impact of this virus on our grapevines is still being understood and currently we do not have a definitive answer. To date we have completed (co-funded by Wine Australia) two studies to assist this understanding:

We also stand to gain valuable knowledge from a PhD research project underway, measuring GPGV spread and diversity of this virus across Australia. We also continue to learn from international peer reviewed papers documenting impact of this virus on industry, as well as actively observing strategies being implemented by international propagation industries to address the presence of GPGV in their propagation supply chain.

Click here for a fact sheet about GPGV.

Process for deregulation
Pending the outcome of industry consultation, if there is support to change the status of GPGV under the Plant Health Act 2009, the following steps will be undertaken:

PIRSA will prepare the notice for the South Australian Government Gazette to revise the declared pest list pursuant to Section 4 of the Plant Health Act 2009, removing Grapevine pinot gris virus.
PIRSA will notify the Minister for Primary Industries and Regional Development of the impending gazettal.
Vinehealth will inform you and the broader South Australian wine industry of the gazettal once it has occurred.
PIRSA will advise the AWRI Commercial Services and CHS Agriculture Victoria virus testing laboratories that any GPGV detections in South Australian grapevine material are no longer reportable.

Seeking your feedback
Vinehealth has provided a high level briefing to the South Australian Wine Industry Association (SAWIA), Wine Grape Council of South Australia (WGCSA) and South Australian Vine Improvement Association (SAVIA) on this matter and we now wish to consult broadly with industry. We seek your support or comments directly on this proposal by 30 July 2021. Feedback can be submitted to Vinehealth Australia, SAWIA, WGCSA or SAVIA contacts below, noting that a lack of feedback will be considered as support for the deregulation.

All feedback provided will be collated by Vinehealth Australia into a deidentified and aggregated form and shared with SAWIA, WGCSA and SAVIA, prior to forming a briefing paper for PIRSA on overall industry sentiment.

We will keep industry informed of any progress in relation to this matter.

Please forward your feedback to any of the below contacts:

Suzanne McLoughlin
Technical Manager
Vinehealth Australia
suzanne@vinehealth.com.au
0412 859 882

Brian Smedley
Chief Executive
SAWIA
admin@winesa.asn.au
(08) 8222 9277

Lisa Bennier
Business Manager
WGCSA
lisa@wgcsa.com.au
0419 039 508

Chris Bennett
Chief Executive
SAVIA
candcbennett@bigpond.com
0419 982 128