The most active corn contract for July delivery fell 5.5 cents, or 1.43 percent to settle at 3.7825 dollars per bushel. July wheat delivery went up 9.75 cents, or 1.91 percent to close at 5.1975 dollars per bushel. July soybeans were down 7 cents, or 0.7 percent to settle at 9.9425 dollars per bushel.
Concerns over unfavorable crop weather in some key wheat growing regions have sent its futures higher. The dryness in eastern Australia, China's north plains and some Black Sea areas may pose threat to wheat production there.
Normal to above-normal rainfall for the majority of the Midwest in the next two weeks, which will provide favorable crop weather for the corn and soybeans, pressured their prices.
Moreover, the uncertainty of U.S.- China trade talks and NAFTA negotiations remains a main concern among farmers and traders, said analysts.