Chicago Board of Trade corn and soybean futures prices should stay historically high this year due to strong demand for food, exports and biofuel production, senior executives from Informa Economics said Monday.Scott Richman, senior vice president with Memphis-based Informa, told the Reuters Global Agricultural and Biofuel Summit from Chicago that new-crop December corn could climb to $5.50 to $6 this spring due to strong demand for exports, livestock feed and corn-based ethanol production....MORE