Understanding and managing Early Bunch Stem Necrosis (EBSN) in the Tumbarumba wine grape growing region

Abstract

Understanding and managing Early Bunch Stem Necrosis (EBSN) in the Tumbarumba wine grape growing region

Summary

This Wine Australia funded project allowed a scoping study and workshop to be conducted on Early Bunch Stem Necrosis (EBSN), a phenomenon which was leading to significant yield losses in the Tumbarumba region of NSW. The aims of the project were to:

1. Conduct a workshop for affected grape growers in the region that addressed possible causes of EBSN and increased grower’s understanding of EBSN and possible causes;

2. Conduct a survey of growers to identify the extent of the problem and quantify the economic losses being incurred;

3. Determine most likely causes of EBSN and develop a research proposal to investigate the problem.

The Tumbarumba Vignerons’ Association in conjunction with the NWGIC developed a workshop seminar program to address the issue of Early Bunch Stem Necrosis (EBSN) and possible causes.

Topics addressed by the workshop seminar included, Managing fruit-set in vineyards, Relationship between carbohydrate dynamics and reproductive development, Physiological disorders of Grape: Bunch Stem Necrosis and Early Bunch Stem Necrosis and Infection of grapevines with Pseudomonas syringe in frost prone region. Tumbarumba growers found the workshop seminar program to be very informative, enabled constructive discussion of the topic, and provided future directions for research into management of the problem. The consensus from the workshop is that Pseudomonas syringae appears to be the most likely cause of EBSN in the Tumbarumba region. Growers also wished to pursue research investigations into P. syringae and its role in EBSN in Tumbarumba wine grapes.