Most viticulturists and vineyard managers are well aware of the problems caused by fungi or moulds such as the mildews and botrytis on the vine canopy but may be less familiar with diseases caused by wood invading fungi. At ground level the collar and root rots caused by Phytophthora and Armillaria may have been experienced, with the former more than likely confined to poorly drained areas in the vineyard, but there is another group of fungi which can cause vine decline in established vineyards.
Damage caused by injury from breakage or pruning, especially after major restructuring procedures in older vines, allows fungi such as Eutypa lata and Botryosphaeria stevensii to enter the woody tissues. It may be two or three seasons later before symptoms appear but usually the early symptoms of stunting, wilting and die back in the cane caused by these organisms progress into the main structure of the vine resulting in the condition known as dead or dying arm disease.
Although horticulture has at its disposal a wide range of chemical fungicides, very few, if any, have proven successful in eliminating fungal pathogens once they have become well established within the woody tissue of roots or vines. Many fungi have suppressive or antagonistic properties towards other fungi and harnessing this bio-activity can offer a solution for the problems of protection and control of this type of disease.
Scientists studying Trichoderma fungi, after the initial 1950’s discovery that it attacked and killed other fungi, have identified strains with activity against the wood-disease causing fungi Phytophthora, Armillaria, Eutypa and Botryosphaeria, as well as root disease pathogens Cylindrocarpon, Rhizoctonia, Pythium and Fusarium.
Vinevax, registered in Australia, harnesses bio-protective properties of Trichoderma into practical products to help the vineyard manager contain and control these economically damaging vine diseases. Vinevax pruning wound dressing can help maintain vine health during vine pruning when wounds are at high risk of pathogen invasion. Vinevax bio-dowel implants can be used to help control woody tissue disease in whole and re-constructed vines aiding faster return of vines to high health and productivity.
Bio-dowels being placed - Henschke vineyard manager Travis Coombe installing a Vinevax Bio-inoculate dowel into the base of a vine.
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