An economic assessment of the impact on the Western Australian viticulture industry from the incursion of grapevine downy mildew

Grapevine downy mildew (Plasmopara viticola) was first detected in commercial vineyards in the Swan Valley region of Western Australia (WA) in 1998 and has now spread to all grape-growing regions of the state. This paper uses a bioeconomic model linking weather, spread, infection development, variable production costs and revenue to estimate the costs of P. viticola over time. Results indicate mean annual costs of AUD $7.3 million per year, equivalent to a 1% drop in the gross value of WA grape-growing industries. Cumulative losses since the disease became established are estimated to be AUD $140 million.