Up to one-third of Muscadet's wine growers are facing financial ruin thanks to a 'meltdown' in export markets amid unsustainable pricing levels.According to Loire Valley wine broker Charles Sydney, around 60 Muscadet vignerons have filed for bankruptcy since this year’s harvest. A total of 150-200 vignerons are expected to go out of business in the next few months. Growers have been hit by a number of factors, including the after-effects of 2008’s devastating spring frost, which destroyed up to two-thirds of the crop - and now vineyards are being abandoned or neglected.