U.S. corn rose for the first time in three sessions on Monday, rebounding off a six-week low, though gains were checked by the U.S Department of Agriculture forecasting stocks at the end of next season at a 12-year high.
Soybeans were little changed, having earlier hit their lowest in nearly three weeks, while wheat rose 0.5 percent.
The Chicago Board of Trade's most-active corn contract climbed 0.5 percent to $3.61-1/4 a bushel by 1213 GMT, having closed down 0.3 percent in the previous session when prices marked a six-week low of $3.52-1/2 a bushel.
Analysts said despite the rise, ample global supplies were capping the contract's gains.
The U.S. Department of Agriculture (USDA) projected U.S. corn supplies would rise to 12-year highs during the 2016-17 crop year as output gains outstrip demand increases.
The USDA last week predicted that U.S. farmers would plant more corn than expected by analysts.
Bumper South American production has also increased supply expectations for the current season, while stagnant demand will see large stocks remaining in silos at the end of the 2016-17 season, analysts say.
The most-active soybeans contract was down 0.1 percent at $8.62-1/2 a bushel, near the session-low of $8.60-1/4 a bushel, which is the weakest since Feb 9.
Soybeans closed down 0.2 percent on Friday. U.S. soybean stocks are expected to fall slightly, but traders said large harvests in South America will maintain significant world supplies.
The most-active wheat contract rose 0.8 percent to $4.56 a bushel, having closed down 0.4 percent on Friday.
The USDA expects the U.S. wheat crop to shed 3 percent to 1.991 billion bushels as the result of a 6.5 percent drop in acreage but this would not be sufficient to prevent a rise in stocks linked to poor demand.
"U.S. wheat is still not competitive on the international market, which will lead to higher stocks next year despite a sharp decline ... in area," consultancy Agritel said.