Fight against grapevine trunk diseases intensifies

Researchers from South Australia and New South Wales are taking the battle to prevent and protect vines against grapevine trunk diseases to a new level, with a new project seeking to give growers more targeted and timely management options.

The three-year collaborative research is being led by the South Australian Research and Development Institution (SARDI) in collaboration with the National Wine and Grape Industry Centre (NWGIC) and is funded by the Australian Grape and Wine Authority.

SARDI research scientist Dr Mark Sosnowski, who is leading the national project, said the research project, which has just entered its second year, would focus on both Eutypa and Botryosphaeria dieback, the two grapevine trunk diseases most prevalent in Australia – and will investigate the diseases from a number of fronts.

The SARDI-based research is being undertaken by Matthew Ayres, with the NWGIC work being led by Dr Sandra Savocchia with the support of Dr Regina Billones Baaijens.

“It takes the extensive work we’ve done in the past on Eutypa, particularly the most recent work that identified effective pruning wound treatments and demonstrated efficient spray application techniques, and moves it to the next level as well as incorporating Botryosphaeria,” Dr Sosnowski said.

“We’re going to look at the timing of application of the fungicides we’ve identified as successful in controlling the grapevine trunk diseases to see when application is most effective, for how long those treatments are effective, and when or if reapplication is needed.

“We are also seeking to identify when the vine is most susceptible during the winter pruning months – and how long that susceptibility might last.”

At the same time, we will undertake spore trapping in four climatically diverse wine regions, to identify when those grapevine trunk disease inoculum are floating around in the vineyards infecting vines and at their most prevalent.

“This particular work is still in development, with the NWGIC team currently designing quantitative DNA primers specific for Eutypa and Botryosphaeria dieback pathogens. These will enable efficient assessment of spore trap tape being collected and stored over the life of the project” he said.

“Ultimately, this will give us some localised condition-based data around the spread and prevalence of grapevine trunk disease.

“Added to the research on timing and susceptibility, it will significantly improve the management and protection package growers can use against grapevine trunk diseases.”

Dr Sosnowski said the research is currently very localised, but it has scope to be broadened to other regions in the future.

“There’s a long way to go, before we have the full story – with highly localised, region-specific tools and management practices, but it will still be a giant step forward in Australian knowledge around grapevine trunk diseases,” he said.

“At the moment, a lot of our current knowledge and practice is based on advice and research undertaken on apricots 40 years ago or on grapes in California – so this will go a long way to providing targeted advice for Australian conditions.”

The SARDI team will also look at resistance potential, with a germplasm trial at its Nuriootpa site investigating what varieties and rootstocks offer greatest resistance against grapevine trunk diseases.

“On top of all that, we are looking at the effect that water deficit irrigation practice might have in disease susceptibility.

“Finally, we are continuing the remedial surgery control work we’ve done with Eutypa dieback and applying it to Botryosphaeria-affected vines, to demonstrate it as a useful control method for both trunk diseases.”

In amongst all this research, Dr Sosnowski and his team will continue to present at research extension workshops and play host to the 9th International Workshop on Grapevine Trunk Diseases, which is sponsored by AGWA and will be held in Adelaide at the National Wine Centre of Australia on 18-20 November 2014.

“The International Workshop is held every two years, and this is the first time it will be held in Australia. It’s a fantastic opportunity to hear and share ideas from leaders in their respective research from around the world and to showcase the work we’re doing here in Australia,” he said.

“I’ve lost count of all the regional trunk disease workshops we’ve held in the past six months, we started in Queensland in November last year, and since then have taken in many of the South Australian and Tasmanian regions.

“The next lot of regional workshops is being planned for Victoria this December,” he said.

A pruning wound trial site in McLaren Vale, which is part of the national grapevine trunk diseases research project led by the South Australian Research and Development Institution (SARDI) in collaboration with the National Wine and Grape Industry Centre (NWGIC).
A pruning wound trial site in McLaren Vale, which is part of the national grapevine trunk diseases research project led by the South Australian Research and Development Institution (SARDI) in collaboration with the National Wine and Grape Industry Centre (NWGIC).