Soyabeans gained ground on optimism over US-China trade talks, while wheat slid, with both markets set to register monthly declines.
The most active corn contract on the Chicago Board of Trade
was up 0.7% at $3.73-3/4 a bushel by 1047 GMT.
Corn prices were on track for an 8.8% fall in August, the largest monthly loss since July 2015. "Bigger days lie ahead as analysts continue to debate the shape of the US corn crop," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia.
The corn market dropped to its lowest in more than three months on Wednesday, pressured by good progress for the US crop after spring floods.
Mild and mostly dry weather is now favouring crop development, agricultural meteorologists said.
The International Grains Council on Thursday raised its forecast for the US corn crop to 341.5 million tonnes, up from a previous projection of 333.5 million but still well below the previous season's 366.3 million tonnes. Global supplies, however, are still expected to tighten, with the year-on-year decline in US production contributing to a deficit of 39 million tonnes for the 2019/20 season.
The most active CBOT soyabean contract rose 0.8% to $8.75-1/2 a bushel but was on track for a monthly loss of 0.7%. Traders were keeping a close watch on the continuing trade conflict between the United States and China.
China, the world's biggest soyabean importer, drastically reduced purchases from the United States after imposing retaliatory tariffs on imports of American soya last year.
The countries are discussing the next round of face-to-face trade talks scheduled for September.
CBOT's most active wheat contract was down 1.3% at $4.66-1/2 a bushel and on track for a monthly loss of 4.2%.