Prices slumped to session lows ahead of the US Federal Reserve statement that was released just before the close of corn trading. The Fed announced it was leaving the target interest rate unchanged, a move that weighed on the dollar and helped lift corn from their earlier lows.
Corn finished about 0.6 percent lower and declined to the lowest level since Oct. 13.
Investment funds were buying back short positions and liquidating longs amid uncertainty ahead of the Tuesday's US presidential election and the US Department of Agriculture's monthly supply and demand report due in a week.
Commodity brokerage INTL FCStone late on Tuesday raised its forecast of the US 2016 corn yield to 175.3 bushels per acre, from 175.2 in October. The firm forecast US corn production at 15.226 billion bushels, up from 15.163 billion last month.