Have you seen grapevine leaf rust symptoms?
Grapevine leaf rust is prohibited matter under the Biosecurity Act 2014. This means that it is an offence to deal with disease.
Be on the lookout for grapevine leaf rust symptoms and report them to Biosecurity Queensland.
Early detection and reporting of symptoms are the key elements in controlling the disease.
Grapevine leaf rust (GLR) is a widely distributed disease of grapevines caused by the wind-borne fungus, Phakopsora euvitis. GLR is common throughout South-East Asia (India to Indonesia) and parts of North America (Florida) and Central America (Jamaica, Columbia and Venezuela).
In 2001, the disease was detected in Australia for the first time in backyard vines in Darwin, the Northern Territory. In 2003, the National Grapevine Leaf Rust Eradication Program began, involving the implementation of a quarantine zone, extensive surveys, removal of diseased vines and monitoring of healthy plants.
The Northern Territory was declared free of GLR on 1 July 2007. Following the Northern Territory detection, surveys were conducted throughout Australia in at-risk rural and urban areas but GLR was not found outside the Darwin area. Biosecurity Queensland continues to perform early detection surveys for GLR in at-risk areas of Queensland.
|What does it look like?||Small, dark spots appear on the upper surface of grapevine leaves (see Figure 1). This is followed by the formation of clumps of small, yellow, powdery spores on the underside of mature leaves (see Figure 2). Infestation may eventually lead to weakening of the vine and leaves dropping off.|
|Symptoms and damage|
As well as spores on leaves, the GLR causes premature defoliation during the growing season. This results in poor shoot growth and a reduction in the quantity and quality of fruit. Its movement into production areas could greatly increase the cost of grape production due to the need to apply fungicides during the growing season.
|Hosts||GLR affects Vitis spp., including commercial and some ornamental grape varieties. It has also been found to infect native Ampelocissus species in the Northern Territory under experimental conditions.|
|Spread||GLR spreads easily through wind-borne spores and the movement of infested plant material.|