NEW YORK—Corn futures fell for a fourth day Wednesday on expectations that record-high prices for the grain will cut into demand for animal feed and ethanol. Soybeans rose sharply.

Other futures traded mostly higher, with gold, silver and copper all rebounding after a big two-day sell-off in commodities. Crude oil inched higher by a penny.

Corn prices rose to a record near $8 a bushel last month as severe flooding swallowed huge swaths of farmland in the Midwest. A dose of warm, dry weather has helped dry out waterlogged crops in recent days, sending prices sharply lowe...