Corn prices are lower as traders expect the government raise its crop production estimate next month.
Corn futures were also falling after China held up some U.S. corn shipments after saying unapproved genetic strains were found.
The actively traded March contract for corn slumped 8.75 cents, or 2 percent, to settle at $4.255 a bushel Friday.
Wheat fell slightly, and soybean futures edged higher.
Energy contracts fell broadly. Benchmark U.S. crude oil for January delivery fell 90 cents, or 0.1 percent, to $96.60 a barrel.
Metals prices were mixed.
Gold rose $9.70, or 0.8 percent, to $1,234.60 an ounce. Silver and copper also edged higher, but platinum and palladium futures fell slightly.