After a slightly lower start, grain prices slid further in afternoon trading, mostly on the backs of  export weakness and strength in the U.S. Dollar index.

At the close,  December 2010 corn futures were 9 1/4 cents lower at $5.64 1/4 per bushel, while November soybeans were 10 1/2 lower at $12.01 1/2 and December wheat was 14 1/4 lower at $6.68 3/4, according to Barchart.com.

Much of the late weakness, especially in the corn pit, came from both retreating export demand and a bounceback in the U.S. Dollar index, according to a report from Dow Jones Newswires.

The Dollar's resurgence Thursday sent all commodities sprawling, including crude oil, which traded down 2%.

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