The Australian Wine Research Institute

The Australian Wine Research Institute Blog

Bacterial inflorescence rot – one possible cause of inflorescence rot or necrosis

19 April 2023 >

19 April 2023

The AWRI helpdesk has received calls this season about necrosis and rot of inflorescences. These symptoms could be caused by a physiological disorder or fungal infection, but could also be the result of a bacterial infection. The purpose of this eBulletin is to raise awareness of the disease bacterial inflorescence rot (BIR), which is caused by the bacterium Pseudomonas syringae pv. syringae (PSS). Awareness of this disease may be relevant when planning pruning practices.

 

About this pathogen
Pseudomonas syringae pv. syringae is a low-risk pathogen in dry and warm seasons, but its development and spread is favoured by wet conditions. It can be particularly damaging in cool regions and humid conditions. Rainfall and the movement of water across leaf surfaces creates the ideal environment for PSS to spread across plant surfaces. The bacterium is understood to enter grapevine leaves through the stomata and spread via the xylem within the shoot. More information about PSS and BIR is available in the AWRI fact sheet: Recognising and understanding bacterial inflorescence rot.


Symptoms in grapevines

Symptoms of BIR (Whitelaw-Weckert et al. 2011) typically first appear at flowering, about 60 days after budburst. They include:

  • brown longitudinal striations on shoots, rachises, leaf petioles and veins
  • necrotic rachises and abscission of up to 60% of inflorescences
  • leaves covered in small dark spots with yellow halos, which enlarge, becoming irregular in shape and bounded by small leaf veins, eventually merging until much of the leaf is covered and the leaf senesces
  • affected tissue splitting due to becoming dry and brittle
  • drops of bacterial ooze near shoot lesions.

The AWRI fact sheet Recognising and understanding bacterial inflorescence rot includes a number of images of BIR symptoms.

 

     

Leaf and inflorescence symptoms caused by Pseudomonas syringae pv. syringae. Images courtesy of Adrian Utter.

 

Testing
If symptoms are observed, it is advised that samples are sent to a testing facility to confirm the cause. Testing is most effective on vines showing early symptoms (e.g. leaves showing small dark spots with yellow halos). Testing is available from:

 

Crop Health Services
Main Loading Dock
5 Ring Road
La Trobe University
Bundoora VIC 3083
Phone: 03 9032 7515
Email: chs.reception@agriculture.vic.gov.au

EMAI (Elizabeth Macarthur Agricultural Institute)
Private Bag 4008
Narellan NSW 2567
Phone: 02 4640 6333
Email: laboratory.services@dpi.nsw.gov.au

Plant Diagnostic Services
Department of Natural Resources and Environment Tasmania
13 St Johns Avenue
New Town, TAS 7008
Phone:  03 6165 3245
Email: plantdiagnosticservices@nre.tas.gov.au
Attention: Alison Dann

 

Management
Pseudomonas syringae pv. syringae is easily spread on pruning equipment. Where PSS has been identified or is suspected, growers should clean and disinfect vineyard equipment regularly, especially pruning equipment. Disinfecting snips and secateurs between plants is recommended to stop the spread.

There are no agrochemicals registered for control of PSS, but copper is thought to have some effect. The application of copper chelate as a soil drench is said to control the pathogen in the vine, but more research would be required to confirm this.

Anecdotal evidence suggests that conversion from spur pruning to cane pruning can reduce PSS pressure, perhaps because old wood harbouring inoculum is removed. Suckers located on the trunk are often found to be infected with PSS and should be removed. High humidity causes symptoms to be more severe, so actions to open the canopy and promote airflow are beneficial.


AWRI helpdesk
For assistance with grapevine diseases or any other technical viticulture or winemaking topic,contact the AWRI helpdesk on (08) 8313 6600 or helpdesk@awri.com.au.

 

Acknowledgement

Fiona Constable, David Lovelock, Cathy Todd, Barbara Hall and Melanie Whitelaw-Weckert are thanked for their contributions to the fact sheet.

This work is supported by Wine Australia, with levies from Australia’s grapegrowers and winemakers and matching funds from the Australian Government. The AWRI is a member of the Wine Innovation Cluster in Adelaide, SA.

Further information

Whitelaw-Weckert, M.A., Whitelaw, E.S., Rogiers, S.Y., Quirk, L., Clark, A.C., Huang, C.X. 2011. Bacterial inflorescence rot of grapevine caused by Pseudomonas syringae pv. syringae. Plant Pathol. 60: 325-337.

NSW DPI Agriculture. Bacterial rot of grapevine caused by Pseudomonas syringae. Video available from: https://www.youtube.com/watch?v=mCmOBuedd1U

For other enquiries
please contact
enquiries@awri.com.au
08 8313 6600

eNews – March 2023

30 March 2023 >

Characterising yeast strains with links to beverages produced by Australia’s Indigenous peoples

Life cycle analysis shows 10% reduction in carbon emissions for Australian wine since 2016

Use the AWRI winemaking calculators to avoid costly mistakes with additives

Affinity Labs launches new method for phos acid

Sustainable Winegrowing Australia impact report available

Register now for the Advanced Wine Technology Course

Save the dates for this year’s Advanced Viticulture Courses

Order the latest AWRI publications online

Acknowledgements

Characterising yeast strains with links to beverages produced by Australia’s Indigenous peoples
Over the course of human history and in societies across the world, fermented beverages have held both economic and cultural importance. In Australia, way-a-linah, an alcoholic beverage produced from the fermented sap of Eucalyptus gunnii, and tuba, a fermented drink made from the syrup of Cocos nucifera fructifying bud, are two of several fermented beverages produced by Australian Aboriginal and Torres Strait Islander people. AWRI researchers and collaborators from the University of Adelaide and ANU isolated yeast strains from two locations in Australia – the Central Plateau in Tasmania and Erub Island in the Torres Strait. Strains were identified using molecular methods and then eight isolates were evaluated for their volatile profile during the fermentation of wort, apple juice and grape must, with diverse volatile profiles observed in the beverages produced. This work was recently published in the journal Food Microbiology and presented by Dr Cristian Varela at the Asia Pacific Section Convention of the Institute of Brewing and Distilling in Adelaide, where attendees also had the chance to taste some of the beers made with these isolates. To find out more, contact the AWRI library to request a copy of the article or email Cristian.Varela@awri.com.au.

Life cycle analysis shows 10% reduction in carbon emissions for Australian wine since 2016

The AWRI recently updated its calculations of the carbon footprint for the production and distribution of Australian wine, in a project funded by Wine Australia. Overall emissions per litre of wine were 10% lower than the previous analysis conducted in 2016. The most important factor driving this drop was the increasing proportion of renewable energy generation in Australia. Increases in bulk wine export and improvements in glass recycling also contributed to emissions reductions. To delve into all the details, read the article summarising this work published in the most recent issue of Wine & Viticulture Journal or contact Kieran Hirlam (Kieran.Hirlam@affinitylabs.com.au).

Use the AWRI winemaking calculators to avoid costly mistakes with additives
The AWRI helpdesk has dealt with several queries this vintage from winemakers who have made errors when making additions, such as over-additions of copper sulfate or sulfur dioxide. This can end up requiring costly remediation steps and additional time and may also have impact on overall wine quality. The AWRI winemaking calculators make it easy to perform a wide range of calculations – minimising the risk of errors. The calculators are available online via the AWRI website or as an app from Google or Apple, which is free within Australia and available for purchase overseas. Download the app now to always have the calculators at your fingertips!

Affinity Labs launches new method for phos acid residue analysis

To support wine producers concerned about the potential for breaching residue limits in export markets, Affinity Labs has just launched a new method for analysing phosphorous acid in grapes and wine. Using the latest liquid chromatography/mass spectrometry techniques, the team can now deliver results within a turnaround time of 10 rather than 15 days. The price for phos acid analysis has also dropped significantly with the launch of the new method.

Phosphorous acid (commonly known as phos acid) is a fungicide registered for use in Australian vineyards, where it is used to treat outbreaks of downy mildew. It is important for wine exporters to understand if their wines have any residues of phos acid, because some export markets including China, Argentina and India, have very low or no tolerance for phos acid residues in wine. Information about residue limits in different markets is available from the AWRI’s agrochemicals online search function and agrochemicals app. To find out more about the new method, or to book in samples for analysis, contact Affinity Labs’ customer service team on 08 8313 0444 or customerservice@affinitylabs.com.au.

Sustainable Winegrowing Australia impact report available
Sustainable Winegrowing Australia has recently released its Impact Report for 2021/22. This is a summary of the national data set that demonstrates the commitment to sustainability of the Australian grape and wine community. The report reveals 48% growth in membership by Australian grapegrowers and winemakers, with the program now representing 40% of total wine production. It highlights the sustainable practices members are undertaking and displays the demand from consumers for sustainably made wine. For more information about Sustainable Winegrowing Australia, visit the program website or contact the AWRI helpdesk on helpdesk@awri.com.au.

Register now for the Advanced Wine Technology Course

The AWRI will present its first Advanced Wine Technology Course (AWTC) in June 2023. This hands-on, intensive, four-day course will cover the latest techniques and technologies in wine production. Participants will travel in a group across a number of South Australian wine regions to visit sites and meet producers at the cutting edge of Australian wine. The course is aimed at winery owners, winemakers, production managers and engineers with an interest in innovation and technology. Participation is limited to a maximum of 20 attendees to ensure an interactive learning experience. Program content includes demonstrations of technologies at small, medium and large wineries; no- and low-alcohol wine and spirits production; innovations in packaging, automation and sensors; structured themed tastings; and technologies from other food and beverage industries. For more information and a link to register, visit the AWTC webpage.

Save the dates for this year’s Advanced Viticulture Courses

Two Advanced Viticulture Courses (AVCs) will be presented in October and November, with the following dates now locked in:

  • AVC #5: 16 –19 October 2023
  • AVC #6: 30 October – 2 November 2023

To express interest in the course and make sure you don’t miss the chance to register, please complete this online form. The events team will contact you with more information prior to registrations opening.

Order the latest AWRI publications online

Accessing the latest AWRI publications is easy. Visit the AWRI Publications web page to:

  • View the 10 most recent AWRI staff publications and order the articles online from the AWRI Library
  • Search the staff publications database
  • Read the full-text of ‘Technical Notes’ from Technical Review (PDF format)
  • Read the full-text of ‘AWRI reports’ and ‘Vineyards of the world columns’ published in Wine & Viticulture Journal (PDF format)
  • Read the full text of ‘Ask the AWRI columns’ published in Australian & New Zealand Grapegrower & Winemaker

The AWRI’s most recent publications are listed below.

2327 Coulter, A. 2023. Ask the AWRI: Wine taints from oak. Aust. N.Z. Grapegrower Winemaker (709): 56-57. (Read online)

2328 Scrimgeour, N. 2023. Achieving success with canned wines. Aust. N.Z. Grapegrower Winemaker (709): 84-87.

2329 Godden, P., Wilkes, E. 2023. Trends in the composition of Australian wine 1990 to 2021. Part one: Introduction, titratable acidity and pH. Wine Vitic. J. 38(1): 20-24.

2330 Scrimgeour, N., Hirlam, K., Hsieh, D., Wilkes, E., Krstic, M. 2023. Canned wine: Looking for a silver lining. Wine Vitic. J. 38(1): 28-34. (Read online)

2331 Dry, P. 2023. Schioppettino. Wine Vitic. J. 38(1): p. 68.

2332 Mierczynska-Vasilev, A.M., Kulcsar, A.C., Dabare, P.R.L., Vasilev, K.A., Bekker, M. 2023. Surface nanoengineering technology for the removal of sulfur compounds associated with negative attributes in wines. npj Sci. Food 7: 5. (Read online)

2333 Bekker, M.Z., Cuijvers, K.M., Kulcsar, A.C., Sanders, R.D., Capone, D.L., Jeffery, D.W., Schmidt, S.A. 2023. Effects of yeast strain and juice nitrogen status on glutathione utilisation during fermentation of model media. Aust. J. Grape Wine Res. 2023: 8041096.

2334 Varela, C., Alperstein, L., Sundstrom, J., Solomon, M., Brady, M., Borneman, A., Jiranek, V. 2023. A special drop: Characterising yeast isolates associated with fermented beverages produced by Australia’s indigenous peoples. Food Microbiol. 112: 104216. (Read online)

2335 Payne, E.M., Taraji, M., Murray, B.E., Holland-Moritz, D.A., Moore, J.C., Haddad, P.R., Kennedy, R.T. 2023. Evaluation of analyte transfer between microfluidic droplets by mass spectrometry. Anal. Chem. 95(10): 4662-4670. (Read online)

2336 Longbottom, M. 2023. Ask the AWRI: Understanding Australian sustainability credentials. Aust. N.Z. Grapegrower Winemaker (710): 45-46.

2337 Mierczyński, P., Mierczyńska-Vasilev, A., Maniukiewicz, W., Vasilev, K., Szynkowska-Jozwik, M. 2023. Novel Cu and Pd-Cu catalysts supported on multi-walled carbon nanotubes for steam reforming and decomposition of methanol. Catalysts 13: 533. (Read online)

2338 Wu, Q., Habili, N., Kinoti, W.M., Tyerman, S.D., Rinaldo, A., Zheng, L., Constable, F.E. 2023. A metagenomic investigation of the viruses associated with Shiraz disease in Australia. Viruses 15: 774. (Read online)

2339 Mierczyński, P., Mierczyńska-Vasilev, A., Vasilev, K., Szynkowska-Jozwik, M.I. 2023. Fourier transform infrared spectroscopic studies of methane and liquefied natural gas reforming processes on Ni/CeO2 catalyst. React. Kinet. Mech. Cat. (Read online)

2340 Godden, P., Wilkes, E. 2023. Trends in the composition of Australian wine 1990-2021. Part two: Alcohol and glucose plus fructose. Wine Vitic. J. 38(2): 30-33.

2341 Hirlam, K., Longbottom, M., Wilkes, E., Krstic, M. 2023. Understanding the greenhouse gas emissions of Australian wine production. Wine Vitic. J. 38(2): 34-36. (Read online)

2342 Dry, P. 2023. Grillo. Wine Vitic. J. 38(2): p. 59.

Acknowledgements

The AWRI acknowledges support from Wine Australia, with levies from Australia’s grapegrowers and winemakers and matching funds from the Australian Government. The AWRI is a member of the Wine Innovation Cluster in Adelaide, South Australia.

New international partnership to benefit food and beverage producers

>

30 March 2023

The Australian Wine Research Institute (AWRI) and leading UK food and beverage services organisation Campden BRI this week announced the signing of a new strategic partnership agreement. Drawing on each other’s significant beverage and food testing capabilities, the AWRI’s commercial arm, Affinity Labs, and Campden BRI will collaborate on new, world-leading services and solutions for customers and members in Australia and the UK. Both organisations are known for taking a science-driven approach to helping their customers and members succeed.

AWRI Managing Director, Dr Mark Krstic, welcomed the alliance, saying “Campden BRI and Affinity Labs have many complementary strengths and experiences providing valuable services to the food and beverage sectors. Our two organisations share similar history, values and culture and can learn a lot from each other. We look forward to expanding the capabilities we provide to Australian food and beverage producers through this strategic partnership.”

Campden BRI Chief Executive, Peter Headridge, said “This new collaboration will provide synergies across a range of sectors and services. We anticipate working closely together on compositional and integrity testing, as well as developing new services for the benefit of food and beverage producers in both the UK and Australia.”

For Affinity Labs, the first activities supported by the partnership will include new options for shelf life testing of foods and beverages that comply with EU and US standards. For Campden BRI, the partnership will initially support the introduction of new wine testing services in the UK, similar to those already offered by Affinity Labs in Australia.

Media contact: Ella Robinson, AWRI Communication Manager – 0402 402 121 or ella.robinson@awri.com.au

About the organisations:

Campden BRI has over 3,000 member companies in 80 countries. We are the trusted, premier, independent technical partner of choice for the food and drink industry and provide a wide range of services and products, all underpinned by investment in meaningful reearch and science. We enable our members in particular to stay ahead of the curve and make the best decisions for their businesses and consumers. Website: campdenbri.co.uk

The Australian Wine Research Institute is the Australian grape and wine industry’s own research organisation. It supports a sustainable and successful grape and wine industry through world-class research, practical solutions and knowledge transfer. Website: awri.com.au

Affinity Labs works with producers and suppliers, from farm to table, providing specialised scientific, testing and quality assurance services. Powered by 60+ years of AWRI research, Affinity Labs is a key food and beverage industry partner, enhancing Australia’s reputation as a world-class primary producer. Website: affinitylabs.com.au

February 2023 Technical Review available now

28 February 2023 >

The February 2023 issue of Technical Review is now available online.

This issue is packed with over 100 current literature articles including ‘Ask the AWRI’ on pinking and wine taints, research into using glycosides extracted from grape marc to boost flavours in NOLO wines, barrel sanitation, wine packaging, sustainable viticulture practices, Graciano, and use of cover crops for weed management.

Australian winemakers and grapegrowers who pay the Wine Grapes or Grape Research levies can log in to read abstracts and order the latest non-open access journal articles from the AWRI Library, free of charge. Register a new login or use the forgotten password link to reset your password.

We welcome your feedback on the new Technical Review and you can reach us at infoservices@awri.com.au.

 

Tips on assessing fruit condition in a season with high disease pressure

22 February 2023 >

22 February 2023 

This season, conditions have been conducive to the development of fungal diseases. As harvest approaches, grapegrowers and winemakers across the country are under pressure to meet quality targets by managing the level of disease-affected fruit entering the winery. This eBulletin provides a reminder of the resources that are available for winemakers and grapegrowers to meet wine quality targets in a fair, equitable and mutually beneficial manner.

Disease assessment
Information about monitoring for key grapevine pest and diseases found in Australia can be found on the pests, diseases and viruses page of the AWRI website. Grape Assess is a digital monitoring tool developed by the University of Adelaide, with funding from Wine Australia, that uses visual techniques to assess diseases and disorders on grapes. Grape Assess can be downloaded for free from the Android and Apple app stores.


The Code of Conduct for Winegrape Purchases
The Code of Conduct for Winegrape Purchases was developed for the Australian wine sector by Australian Grape & Wine (AGW) and its Code Management Committee (a committee with equal representation of winemakers and grapegrowers). The Code sets minimum standards relating to grape purchasing, including mechanisms for determining price; quality assessment for the purpose of affecting price; and payment terms.

The Code is a non-prescribed voluntary industry code. Winemakers who elect to become signatories are governed by this Code in their commercial dealings with growers. Where the Code is incorporated into a contract by reference, it has contractual force. There are currently 72 signatories of the Code, representing 60-70% of the Australian winegrape crush. A list of signatories can be found here.

Grapegrowers and winemakers are encouraged to familiarise themselves with the Code to ensure they know their obligations and rights.


Fruit condition assessment
Key points from The Code related to fruit condition assessment are summarised below.

  • A grower should always have the right to be present during a vineyard inspection and this should be encouraged.
  • When assessing grapes against MP&C standards (mature, pure and in good condition) or grading them or otherwise making assessments of grapes, signatories must:
    1. (1) avoid the use of subjective measures to determine price, in circumstances where there are credible objective measures readily available to measure the same or similar characteristics;
    2. (2) where available, use Industry Endorsed Standard Procedures; and (3) clearly document their methodology and results, and retain that documentation.
  • Notification of possible downgrading, penalties or rejection will be in accordance with timeframes laid out in the Code (for Code signatories) and in any case as early as possible with consideration to the fact that the grower may wish to seek alternative arrangements to prevent further loss. Furthermore, identifying problems as early as possible allows the grower the opportunity to take action that might avoid grapes being downgraded or rejected.
  • The timing and methodology of these assessments should be specified in the grower supply agreement and, where an adverse assessment decision is made, evidence to justify the decision should be documented and be accessible to each party in the event of a dispute (this is a requirement of signatories to the Code).

Industry endorsed standard procedures
Australian Grape & Wine has produced an industry endorsed standard procedure for testing winegrapes for Brix or colour and has also produced sampling guidelines for collecting grape samples in the vineyard for Brix and colour assessment.

Although there is currently no industry-endorsed standard procedure for pest and disease assessment in the vineyard, the recently updated booklet on winegrape assessment (Hooper and Wilkes 2022) provides the following useful guidelines:

  • Use the disease assessment key from Emmett et al. (2015) to quantify the percentage incidence and severity rating of disease in the vineyard.
  • Commence assessment of disease in the vineyard by veraison at the latest, or earlier if resources allow.
  • Conduct assessments of disease in association with the winemaker/grape purchaser.
  • Ensure assessors are trained in the technical assessment of pests and diseases that can affect wine quality.
  • Use an assessment method that produces results that are statistically valid, taking account of vineyard variability. Retain accurate and consistent documentation to support this.
  • To ensure thorough monitoring, conduct 200 observations per ‘hot spot’ or block, stopping to assess 20 sites and assessing 10 bunches or leaves at each location by choosing one to five vines. Growers are advised, however, to consult purchasing wineries regarding their disease assessment protocols.

Dispute resolution
Information about dispute resolution can be found on the Dispute resolution page of the AGW website or by contacting the Code Secretariat on codesecretariat@accordgroup.com.au or (02) 9264 9506.


AWRI helpdesk
For assistance with grape assessment or any other technical viticulture or winemaking topic, contact the AWRI helpdesk on (08) 8313 6600 or helpdesk@awri.com.au


References and further reading
ACCC. 2019. Wine grape market study – final report.
Australian Grape & Wine Inc. 2021. Code of Conduct for Australian Winegrape Purchases.
Hooper, A., Wilkes, E. 2022. Winegrape assessment in the vineyard and at the winery.

eNews – January 2023

25 January 2023 >

AWRI Annual Report available

Update on Wine Australia-funded impact project development

First look at Practices Survey results

Affinity Labs sample pick-up service launching in Murray Darling

Wine Australia sustainability survey now open

Non-chemical weed control: history and current resources

Sustainable Winegrowing Australia, FY22 Impact Report – coming soon!

Free access to eBooks

Order the latest AWRI publications online

Acknowledgements

AWRI Annual Report available
The 2022 AWRI Annual Report was sent out to levy payers in December and is also now available from the AWRI website. This year’s report includes updates on research, development and extension projects; highlights from the year; financial statements; and summaries of a wide range of activities. Visit our Annual Reports page to access the latest report and find previous years’ reports, dating back to 1999!

Update on Wine Australia-funded impact project development

Over recent months the AWRI and Wine Australia have been working together closely on a process for co-designing ‘impact’ projects under three themes:

  • No- and low-alcohol (NOLO) wines
  • Wine production and quality
  • Sustainability

This has involved facilitated workshops and detailed conversations with industry members in roles across the value chain. A range of initiatives are now being developed for assessment and prioritisation. This new process will deliver outcomes for which the target audience for innovation is clearer and the associated opportunities and barriers are better understood, all of which will translate into a greater direct impact on our industry’s sustainability and profitability. The impact project teams at the AWRI would like to thank all industry members who have taken part in conversations supporting this process, and are excited about continuing to work closely with industry partners in the future. Updates on the initiatives under development will be provided in future issues of AWRI eNews.

First look at Practices Survey results
Late last year Simon Nordestgaard presented a webinar with some early results from the AWRI Vineyard & Winery Practices Survey. Drawing on responses from one of the key questions in the survey, the webinar discussed the products and equipment nominated by Australian grapegrowers and winemakers as having had the biggest positive impact on their operations over the last six years. If you missed it in the December rush, you can watch the recording now. More results from the survey will be released later in the year.

Affinity Labs sample pick-up service launching in Murray Darling

Affinity Labs is offering a new flow cytometry-based method known as BrettCount for detecting viable Brettanomyces cells in wine. This method uses a mixture of fluorescent gene probes targeting different regions of the 16s ribosomal RNA of Brettanomyces cells to rapidly detect and quantify them in wine. The method has high specificity and does not cross react with other species that may be present in wine. The limit of detection is 100 cells/mL. Only viable cells are detected, although some cells that are not culturable under laboratory conditions can also be detected. BrettCount is rapid, with results obtained within one day. A recent comparative study showed that BrettCount correlates better with the ‘gold standard’ selective plating method than other rapid methods. For more information or to submit samples for BrettCount analysis, contact customerservice@affinitylabs.com.au.

Wine Australia sustainability survey now open

Wine Australia is currently seeking input to assist with the development of an Environmental, Social and Governance (ESG) Business Plan for the Australian grape and wine sector via a short survey. While the terminology of ‘ESG’ may be new to some, it relates to the sustainability of the planet, people and profit (or prosperity). Globally, there are increasing market pressures to provide sustainability credentials or increased reporting and proof of business processes relating to environmental, social and governance measures. To ensure that Australian grape and wine businesses of all sizes are well positioned to respond to this fast-evolving landscape, you are encouraged to participate in the survey to share the challenges and opportunities your business is facing. The survey is open until 3 February 2023 and can be accessed here.

Non-chemical weed control: history and current resources

In recent years Australian grapegrowers have shown increasing interest in trialling and adopting non-chemical techniques for controlling weeds in vineyards. The AWRI’s non-chemical weed management webpage contains a range of resources relevant to this topic, including an online tool to help growers choose the best option(s) for their situation and a recently published article on the development of undervine weeding equipment. To discuss weed control options or any other technical viticulture or winemaking topic, contact the AWRI helpdesk on helpdesk@awri.com.au.

Sustainable Winegrowing Australia, FY22 Impact Report – coming soon!
Keep your eyes out for the upcoming Sustainable Winegrowing Australia Impact Report which will be released in late February, supported by a media campaign from March. This report presents the national sustainability data of members from financial year 2022. It highlights the actions members are taking to reduce water and use alternative energy sources, decrease waste, improve soils, increase biodiversity and contribute to their communities. It also features several certified members and the difference they are making. The report will be made available on the Sustainable Winegrowing website by the end of February. In the meantime you can access the previous year’s Impact Report.

Free access to eBooks

Did you know that Australian grapegrowers and winemakers have free access to 250 viticulture and oenology eBooks from the AWRI library?

eBooks can be read online or downloaded to your device to read offline. You can also print or save up to one chapter or 10% of the book. To explore the wide range of eBooks available, log into the library database using your AWRI website login.

The AWRI Library adds new eBooks regularly and new purchase suggestions are welcome. Contact the library team on infoservices@awri.com.au to suggest a book or if you need any assistance with accessing the library database.

Recently added eBooks on topics including flavour, soil, marketing, sustainability, pests, wine quality and analysis are listed below.

Order the latest AWRI publications online

Accessing the latest AWRI publications is easy. Visit the AWRI Publications web page to:

  • View the 10 most recent AWRI staff publications and order the articles online from the AWRI Library
  • Search the staff publications database
  • Read the full-text of ‘Technical Notes’ from Technical Review (PDF format)
  • Read the full-text of ‘AWRI reports’ and ‘Vineyards of the world columns’ published in Wine & Viticulture Journal (PDF format)
  • Read the full text of ‘Ask the AWRI columns’ published in Australian & New Zealand Grapegrower & Winemaker

The AWRI’s most recent publications are listed below.

2312 Cordingley, B., Coulter, A., Cowey, G., Dixon, R., Essling, M., Holdstock, M., Longbottom, M., Penfold, C., Pitcher, L., Schwarz, C., Simos, C., Krstic, M. 2022. Vintage 2022 – observations from the AWRI helpdesk. Wine Vitic. J. 37(4): 36-38.

2313 Corsi, A.M., Dolan, R., Goodman, S., Pearson, W. 2022. Exploring the attitudes and expectations of Australian drinkers and non-drinkers towards low and no-alcohol wines. Wine Vitic. J. 37(4): 70-72.

2314 Dry, P., Smart, R. 2022. Varietal choice for a warmer future. Wine Vitic. J. 37(4): 54-61.

2315 Dry, P. 2022. Pecorino. Wine Vitic. J. 37(4): p. 67.

2316 Ismail, I., McKay, S., van den Heuvel, S., Borneman, A., Sosnowski, M. 2022. Evaluation of spore collection methods for detection and quantification of fungicide resistance in powdery mildew. Wine Vitic. J. 37(4): 46-52.

2317 Nordestgaard, S. 2022. History and recent developments in under-vine weeding equipment. Aust. N.Z. Grapegrower Winemaker (705): 50-61.

2318 Schwarz, C. 2022. Ask the AWRI: How’s the weather? Aust. N.Z. Grapegrower Winemaker (705): 50-61.

2319 Dixon, R., Cowey, G. 2022. Vineyard nitrogen management in a urea-limited world. Aust. N.Z. Grapegrower Winemaker (706): 54-55.

2320 Ntuli, R.G., Saltman, Y., Ponangi, R., Jeffery, D.W., Bindon, K., Wilkinson, K.L. 2022. Impact of skin contact time, oak and tannin addition on the chemical composition, color stability and sensory profile of Merlot wines made from flash détente treatment. Food Chem. 405: 134849.

2321 Mierczyński, P., Dawid, B., Mierczynska-Vasilev, A., Maniukiewicz, W., Witońska, I., Vasilev, K., Szynkowska-Jóźwik, M.I. 2022. Novel bimetallic 1%M-Fe/Al2O3-Cr2O3 (2:1) (M = Ru, Au, Pt, Pd) catalysts for Fischer-Tropsch synthesis. Catal. Commun. 172: 106559. https://doi.org/10.1016/j.catcom.2022.106559

2322 Jiang, W.W., Bilogrevic, E., Parker, M., Francis, I.L., Leske, P., Hayasaka, Y., Barter, S., Herderich, M. 2022. The effect of pre-veraison smoke exposure of grapes on phenolic compounds and smoky flavour in wine. Aust. J. Grape Wine Res. DOI: 10.1155/2022/9820204.

2323 Henschke, P., Borneman, A. 2022. Clonal mapping of Pinot Noir: Loss of source blocks in Adelaide Hills bushfires leads to clonal identification for Pinot Noir. Aust. N.Z. Grapegrower Winemaker (707): 35-37.

2324 Cowey, G., Schmidt, S. 2022. Ask the AWRI: Winery nutrient management in a DAP-limited world. Aust. N.Z. Grapegrower Winemaker (707): 46-47.

2325 Krstic, M. 2022. Australian Wine Research Institute: Annual Report 2022. Aust. N.Z. Grapegrower Winemaker (707): 76-79.

2326 Cordingley, B. 2023. Ask the AWRI: Thinking about pinking. Aust. N.Z. Grapegrower Winemaker (708): 46-47.

Acknowledgements

The AWRI acknowledges support from Wine Australia, with levies from Australia’s grapegrowers and winemakers and matching funds from the Australian Government. The AWRI is a member of the Wine Innovation Cluster in Adelaide, South Australia.

AWRI and Affinity Labs Christmas closure

21 December 2022 >

21 December 2022

Christmas closure and support during the break

The AWRI will be closed over the Christmas/New Year period from midday on Friday, 23 December and will re-open at 8:30am on Tuesday, 3 January 2023.

Affinity Labs
Affinity Labs will be closed from midday on Friday, 23 December and will re-open at 9:00am on Monday, 9 January 2023.

Helpdesk support
Telephone support will be available for urgent or emergency assistance while the AWRI is closed. If you require urgent assistance, please contact:

  • Geoff Cowey on 0448 736 145 for winemaking issues.
  • Marcel Essling on 0418 816 311 for viticulture issues.

For less urgent queries, please email helpdesk@awri.com.au and the team will get back to you when the AWRI re-opens.

Sustainable Winegrowing Australia support
For any enquiries about Sustainable Winegrowing Australia, please email helpdesk@awri.com.au and the team will get back to you when the AWRI re-opens.

Library
The John Fornachon Memorial Library will be closed from midday on Friday, 23 December and will re-open at 9:00am on Monday, 9 January 2023. Access to the library’s online database will continue to be available 24 hours a day, 7 days a week via the AWRI website.

December 2022 Technical Review available now

20 December 2022 >

20 December 2022

The December 2022 issue of Technical Review is now available online.

The new format offers a more convenient and seamless experience. Articles available online are linked directly to publishers’ websites where you can read full-text articles. Australian winemakers and grapegrowers who pay the Wine Grapes or Grape Research levies can log in to read abstracts and order the latest non-open access journal articles from the AWRI Library, free of charge. Register a new login or use the forgotten password link to reset your password.

We welcome your feedback on the new Technical Review and you can reach us at infoservices@awri.com.au.

 

Agrochemical update: emergency use permit for Nufarm Amishield Fungicide

12 December 2022 >

7 December 2022

The APVMA has issued an off-label permit (PER93023) enabling the use of Nufarm Amishield Fungicide (APVMA No. 88958) on grapevines. It is essential that growers read the permit prior to use and comply with all the conditions. The permit has been issued due to possible shortages of the products registered for grapes. The permit is available from the APVMA website.

Products:

NUFARM AMISHIELD FUNGICIDE (APVMA Approval No. 88958)

Directions for use:

Crop

Disease

Rate

Grapevines

Downy mildew
(Plasmopara viticola)

16 g/100 L

PLUS

125-350 mL/100 L
Nufarm Tri-Base Blue
Fungicide (APVMA No. 53568)

OR

The registered rate for
downy mildew in
grapevines for a product
with an alternative mode
of action to Group 21

 

Important things to note:

The permit is valid for a limited period (2 December 2022 to 31 May 2023). Growers should not buy more than is needed for this season, because excess stock will not be permitted for use in subsequent seasons.

It is a condition of the permit that any Nufarm Amisulbrom Fungicide spray includes another registered downy mildew protectant fungicide.
Critical use comments:

  • Apply as a protectant spray to grapevines commencing after shoots are 10 cm long.
  • DO NOT use later than E-L 31, berries pea size (not > 7 mm diameter) on grapes grown for export wine production.
  • DO NOT apply more than two consecutive applications and do not apply more than four applications per season. If consecutive applications are made, they should be 7 to 10 days apart and followed by two applications with an alternative mode of action before resuming applications of tank mixtures containing amisulbrom.
  • Refer to the restraints and critical comments on the tank mix partner label before use.
  • Apply as a foliar spray by air-blast sprayer. Apply sufficient volume to wet all leaf surfaces up to the point of run-off.

Additional comments:

To avoid crop damage
The sensitivity of the crop to be treated under this permit has not been fully evaluated. The APVMA advises to only treat a small area to ascertain the reaction before treating the whole crop. Nufarm Australia does not consider crop sensitivity to be a risk when the conditions of the permit are followed. For more information, contact the AWRI, your Nufarm representative or your chemical on-seller.

Withholding period:

Harvest: DO NOT harvest for 4 weeks after last application

Note: DO NOT use later than E-L 31, berries pea size (not > 7 mm diameter) on grapes grown for export wine production.

Note: With the use of this permit in a tank mix with another product, the longest of the products’ withholding periods would apply.

For grapes destined for export wine users should refer to recommendations as included in the AWRI publication Agrochemicals registered for use in Australian viticulture 2022/2023.

Growers with any concerns regarding use should contact their grape purchaser or winery.

Jurisdiction:

ALL States and Territories.

For more information or to request a copy of the ‘Dog book’, please contact the AWRI helpdesk on (08) 8313 6600 or email helpdesk@awri.com.au.

This information is provided to inform the Australian grape and wine sector and should not be interpreted as an endorsement of any product.

For assistance with any technical grapegrowing or winemaking questions, contact the AWRI helpdesk on helpdesk@awri.com.au or 08 8313 6600.

Warning about disease pressure

25 November 2022 >

25 November 2022

Following an eBulletin on 27 October 2022, which focused on downy mildew, this is a reminder that weather conditions in some regions this season are also likely to be highly conducive to the development of powdery mildew and botrytis bunch rot. These diseases have a habit of ‘flying under the radar’ and then emerging just before Christmas or harvest at levels that are very difficult to control. Growers are encouraged to take steps now to avoid disease problems closer to harvest.

Powdery mildew
Powdery mildew in grapevines is caused by the fungus Erysiphe necator. The distinctive grey-white powdery growth affects green tissue, including leaves, shoots and fruit, and has negative impacts on both grape yield and quality. All grapevines are susceptible to powdery mildew, but the risk is greatest in vineyards that were affected by an outbreak in the previous season. Some varieties are particularly susceptible, namely Chardonnay, Semillon and Verdelho. Powdery mildew can develop and progress independently of free moisture. The conditions that favour the development and spread of the disease are mild weather (20 – 30°C), low light levels and relative humidity greater than 40%.

Controlling powdery mildew
The ideal spray program for powdery mildew involves regular applications of protectant chemicals early in the season, effectively protecting all growth from the disease. Stopping the disease from getting established early in the season is critical in reducing the disease load later in the season. Unfortunately, this season has not allowed for early-season sprays to be applied in many vineyards, or the sprays that have been applied have been hit with periods of heavy rain which may have diluted them. These circumstances have created a high level of risk for powdery outbreaks. Where this is the case, action to prevent an epidemic of powdery disease is paramount.

Elemental sulfur is a multi-site fungicide which is not susceptible to resistance and has some curative activity. To gain control of an existing infection using sulfur, good spray coverage is essential. This can be confirmed using wettable paper or a short run with a kaolin clay tank mix. If there are gaps in coverage, it is advisable to adjust one setting on your tractor or spray unit at a time and re-test until good coverage is achieved.

An active powdery mildew infection can be water repellent, so it is important to check that enough spray is reaching all targets. Growers should consider using an adjuvant to improve coverage on what is a hard to wet surface. Some sulfur products such as Thiovit Jet and Microthiol Disperss have an adjuvant built into the formulation, which improves spread on the plant surfaces. Many other sulfur products may require some assistance with spread, so check with your chemical on-seller if an adjuvant is required.

Some single site chemicals are known to have curative activity against powdery mildew but their use against active infection is not recommended due to the increased risk of resistance development. The CropLife Australia recommendation for single site fungicides is that they should be applied before colony formation (preventatively) for powdery mildew control.

Elemental sulfur is in short supply so it’s important to plan how you will use the chemical stock you can access. It is recommended to allocate sulfur to those blocks where a powdery curative is required and use other agrochemicals where powdery mildew has been contained and prevention is still an option. Monitoring is important and instructions on how to recognise powdery mildew are provided in the resources linked below. Consult with your grape purchaser or the AWRI if you are considering chemical options that do not follow the ‘Dog Book’ recommendations for export wine.

Operating a spray unit in the same direction for every spray runs the risk of missing the same hard-to-reach parts of the canopy each time, potentially creating a powdery mildew hotspot. Spraying in a different pattern so that the opposite direction is travelled up the row has the potential to improve overall coverage.

Canopy management practices are an essential part of managing disease risk, especially in challenging seasons. Manipulation of canopy conditions to allow light, air and agrochemical sprays to reach the ‘inside’ foliage helps create a more challenging environment for fungal diseases, including powdery mildew, downy mildew and botrytis bunch rot.

Botrytis bunch rot
Botrytis bunch rot is caused by the pathogen Botrytis cinerea, which is a common environmental fungus that enters grapevine tissue through wounds (including scarring from powdery mildew infection and natural openings) and takes hold once the right conditions are met. Effective Botrytis management requires an integrated approach using both chemical and cultural control measures.

Flowering (E-L 25) and pre-bunch closure (E-L 31) are recognised as the critical growth stages for Botrytis sprays; however, rain and/or high humidity at or around harvest can cause devastating losses in a short period of time. Getting good coverage of the bunch zone is critical with any Botrytis spray, so take the time to check that you are hitting the intended target. Consider the potential entry points for Botrytis infection from initiation of flowering onwards, factoring how growing conditions could affect the risk of Botrytis infection. Also consider previous disease load in your vineyard and the susceptibility of your variety mix when designing control strategies.

New Zealand research investigating various cultural practices to reduce Botrytis risk in high pressure years found that leaf plucking to maintain 70-90% bunch exposure from late flowering to pre-harvest was the most effective treatment (Andrew and Lupton 2013). However, leaf plucking should be applied with care, since excessive leaf removal may result in sunburn, especially if applied later in summer in hot regions. Removing the trash from inside and around developing bunches post-flowering, using a harvester or pulsed air leaf plucker, can also reduce Botrytis risk by taking away a source of Botrytis inoculum and altering the bunch environment for improved airflow and bunch drying.

Reference
Andrew, R., Lupton, T. 2013. Understanding Botrytis in New Zealand vineyards, Auckland, New Zealand: New Zealand Winegrowers: 215 p.

Additional resources
· The AWRI’s resources on powdery mildew
· The AWRI’s resources on Botrytis
· Ask the AWRI publication – Spray application
· Wine Australia’s resources on powdery mildew
· Wine Australia’s resources on Botrytis

AWRI webinars
· Getting the most out of ‘biological’ sprays for Botrytis control (October 2021)
· Late season Botrytis: the disease and options to control it (February 2021)
· Fungicide resistance in Australian viticulture (January 2022)

Acknowledgements
Liz Riley (Vitibit), Kerry DeGaris (Treasury Wine Estates), Warren Birchmore (Accolade Wines), Philip Deverell (Pernod Ricard Winemakers), Scott Paton (Nutrien Ag Solutions) and Scott Mathew (Syngenta Australia) are thanked for their contributions to this eBulletin.

For more information or assistance, please contact the AWRI helpdesk on
08 8313 6600 or helpdesk@awri.com.au.