From the Wall Street Journal:

Evidence of tightening global food supplies grew as the U.S. Agriculture Department cut its estimates for global harvests of key crops and raised some demand forecasts, adding to worries about rising food prices.

Prices of corn and soybeans leapt 4% Wednesday and wheat gained 1%, continuing the broad rally in commodity prices that began in June.

The USDA's revisions reflect the impact of dry weather in South America and floods in Australia, which have compounded supply constraints that first started to emerge in the middle of last year, when a drought in Russia ravaged that country's wheat fields.

Prices Soar on Crop Woes