Australia's wine industry needs to show a more united front to defend market share and create opportunities in emerging markets, South Australia's Agriculture Minister Michael O'Brien says. The nation also needs to learn lessons from past experiences in order to reposition itself as a quality wine producer, the minister told a wine industry day in Adelaide. "I think we have debased and debauched the Australian brand in the UK market - with the two-for-one offers and all the rest of it. We don't want to make that mistake in the rest of the world."