Argentine wheat gets frost, adding to supply jitters

Frosts struck wheat fields in grains giant Argentina this week, unsettling growers who already expect a meager harvest this season due to a 20 percent decline in plantings.

It will take several days to judge the impact of the Monday-Wednesday cold snap, however. Exporters are eager to know about Argentina's 2012/13 crop, after droughts in the United States and Russia and dry weather in Australia's western wheat region have squeezed global supply.