Chicago Board of Trade corn futures ended lower on Wednesday on spillover weakness from wheat and soyabeans, and an active US planting pace that has bolstered forecasts for a record-large US corn harvest in 2020, traders said.

Benchmark CBOT July corn settled down 4 cents at $3.18-1/4 per bushel but stayed inside of Tuesday's trading range.

Underlying support noted from traders unwinding long soybean/short corn spread positions.

Futures were also underpinned by supportive weekly data for corn-based ethanol. The US Energy Information Administration said weekly ethanol output rose for a second week, to 617,000 barrels per day, while stockpiles fell for a third week to 24.190 million barrels.