It was a big day for the bulls in the CME Group grain pits Wednesday, with corn, soybeans and wheat closing sharply higher.

At the close, the December 2010 corn futures contract ended 27 1/2 cents higher at $5.73 1/2 per bushel, while November soybeans were 32 cents higher at $12.12. December wheat ended 11 1/2 cents higher at $6.83 per bushel.

Many anaylsts say a reversal of the U.S. Dollar index -- which had been showing signs of major strength in the past few days -- is largely behind Wednesday's rally in the grains. There was also more commercial and speculative buying as prices broke, as well as some growing speculation about the 2010 crops as harvest winds down, both of which helped buoy the grains.

• See more on Wednesday's corn trade
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