The most active corn contract for May delivery fell 3.75 cents, or 0.97 percent to settle at 3.825 dollars per bushel. May wheat delivery went down 10.25 cents, or 2.17 percent to close at 4.6225 dollars per bushel. May soybeans lost 12.25 cents, or 1.16 percent to settle at 10.42 dollars per bushel.
CBOT floor brokers reported that funds sold 5,300 contracts of corn, 6,400 contracts of Chicago wheat and 2,400 contracts of soybeans.
Dryness in Kansas, Oklahoma and Texas has led to bad ratings of wheat crops there. The three wheat growing states have seen little rain for months.
According to forecasts, as much as four centimeters of rain would fall in the region later this week, which would give thirsty winter wheat crops much-needed water.
As a result, wheat prices continued to fall for the fourth consecutive session as weather conditions improved.
Market observers said that weak demand for U.S. wheat put additional pressure on the CBOT market.
CBOT soybeans, which had posted gains of more than 20 cents last week, fell sharply on Monday due to profit-taking.