Corn prices are sharply lower after the U.S. government reported a surprisingly large increase in ethanol supplies.
The actively traded March contract for corn fell 9 cents, or 2.1 percent, to $4.17 a bushel on Wednesday.
Besides higher ethanol supplies, which suggests that demand could be weakening for the fuel, traders are also worried that the U.S. Department of Agriculture could raise its production estimate for last fall's crop on Friday and report higher corn stockpiles.
Wheat also fell sharply. The March contract lost 13.75 cents, or 2.3 percent, to $5.8875 a bushel.
March soybeans edged down 6.75 cents, or 0.5 percent, to $12.6925 a bushel.
Other commodities also fell. Crude oil fell $1.34 to $92.33 a barrel and gold edged down $4.10 to $1,225.50 an ounce.