 December corn futures opened slightly lower and then fell to spike support at Monday's low of 405.75, then recovered to settle just above that level. Much of the price pressure is tied to this week's rains in the eastern Corn Belt, which are expected to improve yield prospects. September corn futures were 1.75 higher, 395.75. December corn down 1.25 cents, 407.25. March corn futures closed at 421, down 2.25 cents.