U.S. corn futures were slightly lower on Monday as the market gave up some of last session's gains due to easing concerns over adverse crop weather in Brazil and the United States.
Soybeans edged up, snapping a three-session losing streak as strong demand from top importer China underpinned the market while wheat was little changed.
The Chicago Board of Trade most-active corn contract fell 0.8 percent to $3.87-3/4 a bushel by 1054 GMT.
"U.S. and South American weather looks largely helpful for corn so the worry level has receded," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia.
A lack of rain has hit Brazil's corn production, while wet weather forced U.S. farmers earlier this month to delay planting that has otherwise been running ahead of the average pace.
Dealers said overall corn supplies remain ample with stocks set to be around record high levels at the end of the current 2015/16 season.
"Corn prices remain dominated by physical surpluses in the major exporting countries, and it is believed that any sustainable rally will have to be driven by a northern hemisphere weather issue," UK merchant Gleadell said in a market note on Monday.
Wheat prices were little changed with Chicago's most active contract up 0.05 percent at $4.75 a bushel, while September wheat in Paris was off 0.3 percent at 163.75 euros a tonne.
Dealers said Chicago wheat prices had been boosted recently by the strong recent pace of U.S. exports although the market remains well supplied after a record global crop in 2015/16.
"More U.S. exports would alleviate the coming harvest indigestion to some degree but it does need to continue," Gorey of Commonwealth Bank of Australia said.
Dealers said European grain markets were thinly traded due to a public holiday in several countries including top EU producers France and Germany.
Chicago's most active soybean contract was up a marginal 0.1 percent at $10.66-1/4 a bushel.
Dealers noted the soybean market had come under pressure during the past few sessions as expectations that farmers are switching planting intentions to the oilseed and away from corn weighed on prices.
There are expectations the USDA's June 30 acreage report could show a shift of 1-2 million acres from corn into soybeans, compared with the government's March 31 planting intentions report.