Diagnosis and management of Eutypa dieback

Abstract

The objectives of this project were to study the epidemiology, management and diagnosis of eutypa dieback to develop integrated management strategies for industry. Growth rate of Eutypa lata varied significantly among cultivars. Foliar symptoms of eutypa dieback varied annually and were not a reliable indicator of infection. A strong correlation was observed between symptom severity and yield loss. Analysis of climate data indicated that rainfall and temperature influenced severity and incidence of foliar symptoms. Numerous treatments were evaluated as pruning wound protectants to prevent eutypa dieback. Bavistin was the most suitable replacement for Benlate, which has been withdrawn from the market. Preliminary studies showed that application using commercial spray equipment may be as effective as applying with a paint brush. Acrylic paints or pastes, with or without fungicides, were also effective wound protectants. Remedial surgery to eliminate E. lata from infected vines was effective in the short– term, however, further research is required to assess the long–term success of this technique. Rapid identification and detection methods for E. lata were developed using polymerase chain reaction and Southern hybridisation techniques to generate specific DNA markers. These markers were used to detect the pathogen in infected wood. Specific biochemical markers for E. lata were identified, however, these could not be detected in the foliage of infected vines.

Summary

Obtain enhanced understanding of the interactions between the vine, pathogen and environment to increase knowledge of the epidemiology of eutypa dieback. Develop improved disease management strategies. Develop a rapid means of diagnosis of eutypa dieback, based on the identification and detection of chemical markers in vinefoliage.