The grapevine trunk diseases Eutypa (ED) and Botryosphaeria (BD) dieback are a threat to the economic sustainability of the New Zealand wine industry. The diseases not only cause significant yield and quality reductions but also shorten the lifespan of vineyards. The risk of grapevine trunk disease increases in vineyards 15 years of age or more.

Reliance on remedial surgery to ‘renew’ infected vines by removing diseased wood and reworking vines to improve productivity is set to increase as vineyards in New Zealand are reaching the age that production is likely to be significantly affected by trunk disease. Because the established root system is retained, remediation is usually more cost-effective for growers than replacement. Anecdotal evidence suggests that yield and fruit quality are restored within several years following treatment but this needs to be substantiated to enable growers to make informed decisions.

The project aims to establish the optimal stage of disease progression and season to conduct remedial surgery; to diagnose the main causal agent of trunk disease and to evaluate vine health and productivity of Sauvignon Blanc, Cabernet Sauvignon and Merlot vines up to four growing seasons following remedial surgery.

Resources available from this project

Video demonstration: How to perform remedial surgery on a grapevine

Article: Management of grapevine trunk disease using remedial surgery

Fact sheet: Grapevine trunk diseases

Project summary

Researchers: Mark Sosnowski, South Australian Research & Development Institute, and Dr Eline van Zijll de Jong, Linnaeus limited

Years: 2019-2023

Funding: Bragato Research Institute

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