The unusually wet season across south-eastern Australia in 2010–2011 saw grapegrowers exhausted after endless hours of spraying, often in vain, to control the dreaded trifecta of downy mildew, powdery mildew and botrytis bunch rot (botrytis). Mildew infection during flowering and fruit set damaged grape berries providing infection sites for the opportunistic ‘wound’ fungi that cause bunch rot. However, the interaction between the diseases was not always detrimental. There were reports that defoliation caused by downy mildew increased air circulation in the canopy which, in turn, reduced the severity of bunch rot. Nevertheless, the pressure on vineyard managers to act in controlling these diseases was relentless, even when certain actions, with hindsight, proved fruitless.
History
Publication title
Proceedings ASVO Seminar - Making the Best Out of Difficult Vintages: Managing Sub-optimal Fruit in the Winery
Editors
Paul R Petrie
Pagination
11-19
ISBN
0 9775256 9 4
Department/School
Tasmanian Institute of Agriculture (TIA)
Publisher
Australian Society of Viticulture and Oenology
Place of publication
Adelaide, South Australia
Event title
Making the Best Out of Difficult Vintages: Managing Sub-optimal Fruit in the Winery