CBOT农产品期货主力合约收盘全线下跌，玉米期货跌0.86%

Group 1 - The core viewpoint of the article highlights a decline in agricultural futures at the Chicago Board of Trade (CBOT) on August 19, with all major contracts closing lower [1] Group 2 - Soybean futures fell by 0.77%, closing at 1033.25 cents per bushel [1] - Corn futures decreased by 0.86%, ending at 403.00 cents per bushel [1] - Wheat futures dropped by 0.81%, closing at 520.75 cents per bushel [1]