Corn and soybeans declined on concern that drier weather will drain fields in the U.S. Midwest, enabling farmers increase planting of crops.
Corn futures for July delivery dropped by 4.9 percent or 30 cents to $5.83 a bushel on the Chicago Board of Trade.
Corn prices increased by 63 percent last year reaching the highest record of $6.23 a bushel on April 17.
Soybean futures for July delivery declined by 4.3 percent or 59.75 cents to $13.1725 a bushel on the Chicago Board of Trade.
Soybeans surged 92 percent last year posting the highest record of $15.8625 on March 3.
Conditions for plant growth were forecasted to improve in the coming two weeks to allow planting of corn and soybeans.
The U.S. Department of Agriculture basing on a survey of farmers early last month forecasted corn planting to decline by 8.1 percent this year to 86 million acres as farmers plant more soybeans due to high costs for fertilizers and fuel that increased costs for corn production compared to other crops.
Soybean planting was forecasted to increase by 1.8 percent to 74.79 million acres higher than 63.63 million acres in 2007.