Australian grapevine yellows – Source, spread and control

Abstract

In investigating the source and spread of AGY, none of more than 12,000 cuttings tested, transmitted disease. Surveys of >130 Chardonnay and Riesling vineyards and 50,000 Riverland, Riverina and Sunraysia vines showed levels of AGY ranged from 1-88% incidence with disease gradients found across vineyards near AGY-hot spots and wasteland vegetation where a native bluebush, ruby saltbush and climbing saltbush, tested PCR-positive for AGY. These are probably the primary hosts of disease. Intensive leafhopper trapping studies indicated that the green jassid and the common-brown leafhopper are prime candidate vectors. The prospects for further investigation are good.

Summary

None of more than 12,000 cuttings tested transmitted the disease. AGY occurs in wild vegetation. Vector still unclear.