Virus-Free Vineyards – The Blog

August workshop line-up

New Zealand Winegrowers’ Virus Elimination Project will once again be hosting workshops in Marlborough and Hawke’s Bay in August.

Nick Hoskins, Project Manager, and Vaughn Bell, Plant & Food Research Scientist, will review:

  • Virus mapping results in your region
  • Regional trends, research and monitoring
  • How to improve mealybug control in your vineyard

The best time to get on top of mealybug control is early in the season, starting just before budburst, so don’t miss the team’s new tips on how to get the best results from your control applications.

If you want more information on this topic, start by downloading our revised fact sheet, ‘NZVE 104 Mealybug control for cropping vines.’ This fact sheet and others related to the management of Leafroll 3 can be accessed from the table found at the bottom right of this page simply by clicking on the links provided.

 

Workshop Schedule

Virus Elimination Project Workshop – Marlborough

  • Tuesday, 5th August 2014
  • 1:30 – 3:30 pm at the Marlborough Convention Centre Hall
  • 42A Alfred Street, Blenheim

Virus Elimination Project Workshop – Hawke’s Bay

  • Wednesday, 20th August 2014
  • 2:00 – 4:00 pm at EIT Lecture Room 2
  • EIT Campus, 501 Gloucester Street, Taradale, Napier 

In appreciation of excellence

Vaughn Bell, a scientist with The New Zealand Institute for Plant & Food Research Ltd, is a key member of the Virus Elimination project and a familiar speaker at our workshops on the North and South Islands. Each year, he reviews selected trial blocks for infection incidence and mealybug populations, reporting back to participants and the wider industry on his findings, which provide valuable insights on vine removal and effective vector control.

In addition, Vaughn is also a PhD candidate with Victoria University of Wellington. For several years, he has been pursuing academic research on the complex interrelationships between Leafroll 3 Virus and its main vector – mealybugs.

Last month, Vaughn submitted his PhD thesis for marking, and Victoria University promptly issued a media release highlighting his valuable contribution to viticultural knowledge benefiting the wine industry.

We’d like to add our own note of appreciation. The Virus Elimination project has benefited from Vaughn’s participation in many ways. In addition to his trial work and related presentations and technical reports, Vaughn also provides thoughtful input to project strategy and is always eager to interact with growers and share knowledge.

To read the media release describing Vaughn’s academic achievement, follow this link while it lasts:

http://www.victoria.ac.nz/news/2014/research-targets-costly-grapevine-disease

Post-harvest wrap up

New Zealand Winegrowers’ Virus Elimination Project has just completed another season of trials, workshops and related activities. This post will provide an update on work leading up to the 2014 harvest, but first, we once again want to acknowledge the efforts of all the growers and viticulturists who are participating in the research and following our protocols for the management of Leafroll Virus 3 and its main vector – mealybugs.

2014 season – what we did

Numbers were up at our most recent series of workshops in Hawke’s Bay and Marlborough in February, with 135 participants in attendance. To help growers with pre-harvest mealybug monitoring and symptom recognition, we literally brought the vineyard into the lecture theatre. On hand were living mealybug samples under microscope, showing the position of the insects in various life stages, plus samples of infected leaves. Excerpts from our video series were also shown, with the emphasis on symptom monitoring for red varieties.

Some attendees from both Hawke’s Bay and Marlborough observed that mealybug populations in some vineyards in 2014 appeared to be higher than in the previous year. As harvest got under way, we once again fielded phone calls and emails from individual growers who had discovered the presence of the vector in their vineyards, along with questions relating to the ‘allowability’ of applying post-harvest mealybug controls.

It’s worth remembering that such applications are not recommended, although a few growers sought and obtained special permission from SWNZ for applying a post-harvest control in problem spots within their vineyards. Rather, the focus should remain firmly on early-season controls starting just before budburst – the time when controls are most effective.

In Marlborough, Leafroll 3 infections were mapped on the four existing trial blocks of Pinot Noir plus another nine trial blocks that have been added since 2013. Pheremone traps for Citrophilus and Longtailed mealybug were distributed to all 13 Pinot blocks and to the four Sauvignon Blanc trial blocks. Once all traps have been returned, our partners at Plant & Food Reseach will assess the results, which should provide useful information regarding the presence of mealybugs in the region’s vineyards.

Yield assessments were completed on two Marlborough Sauvignon Blanc blocks. A total of 85 ELISA-positive (infected) and 85 ELISA-negative vines were harvested and weighed separately. Brix, PH and TA were also assessed. Early indications are that results this year may have been hampered by the extensive crop thinning that was seen over much of the region.

The ongoing tagging of Leafroll 3 infections across the Gimblett Gravels started in March, and, with an early harvest for many growers, was all but completed by the last week of April. Approximately 80% of tagged vines have now been mapped. Once complete, this data will be collated and maps created for individual growers and the area as a whole.

A new fact sheet, ‘Testing white varieties for Leafroll 3,’ was presented to workshop participants and distributed via the March 2014 issue of NZ Winegrower magazine. Other fact sheets have been revised and new PDFs for NZVE 101, NZVE 108 and NZVE 109 can be downloaded from this page (see the box on the lower right).

All in all, it’s been another busy – and gratifying – year for the Virus Elimination Project team, and we’re looking forward to analysing and then sharing all the information with the wine industry. And there’s more to come, so watch this space for news in the near future.

About

Welcome! This blog is maintained by members of the Virus Elimination Project, a New Zealand Winegrowers' Research Project that is co-funded by the Ministry for Primary Industries (Sustainable Farming Fund).

The Virus Elimination Project has three main objectives:

  1. Identify and map the presence and/or spread of Grapevine Leafroll-associated Virus 3 (Leafroll 3) in participating vineyards in New Zealand.
  2. Contain and control Leafroll 3 virus and the main vector – mealybugs – through a programme that comprises vine removal/replants, hygiene practices and insect control.
  3. Develop “best practice” guidelines for New Zealand Winegrowers, with the long-term goal of maintaining virus-free vineyards.

Control and management of Leafroll 3 is a community issue. That’s why the project trains growers to identify leafroll virus, map, treat, and remove infected vines on an area-wide basis in tandem with effective control of mealybugs. We welcome your comments and questions on this blog.

Click here to read disclaimer.

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