Corn futures at the Chicago Board of Trade were lower early Tuesday on spill-over weakness from soybeans and prospects for a huge 2004 US corn crop, traders said.
Traders have been talking about the possibility of US farmers harvesting 11 billion bushels of corn, which would smash all previous records.
But the market opened firm on a surprising decline, rather than an increase, in condition ratings for the corn crop.
CBOT corn futures were 1/2 cent to 1-1/4 cent per bushel lower by 9:50 am CDT (1450 GMT). September was down 1 cent at $2.17-1/4 and new-crop December was 1-1/4 cent lower at $2.26-1/2.
Volume was thin early in the session. Fimat Futures was noted selling 100 December, floor traders said.
The US Department of Agriculture said late Monday 76 percent of the corn crop was in good to excellent shape, down from 77 percent last week. Traders expected condition ratings to be steady or increase by 1 percentage point.