Chicago Board of Trade corn futures ended modestly higher on Wednesday on signs of fresh export demand for US supplies and bargain buying after last week's multi-year lows, traders said.
CBOT May corn settled up 1-1/4 cents at $3.48-1/2 per bushel.
The US Department of Agriculture said private exporters sold 138,000 tonnes of US corn to unknown destinations.
Ahead of Thursday's weekly USDA export sales report, analysts expected the government to report export sales of US corn in the week to March 19 at 900,000 to 1,900,000 tonnes.
The US Energy Information Administration said weekly US output of corn-based ethanol fell for a third week, to 1.005 million barrels per day, while stockpiles fell to 24.140 million barrels.
The Trump administration has decided not to appeal a court ruling that would sharply reduce its use of waivers exempting refineries from the nation's biofuels regulation, cheering the corn lobby but drawing anger from oil refiners.