The uptrend in soybeans didn't last long Wednesday, and the January contract ended an up-and-down day in the red.

At the close, March corn was 9 1/4 cents higher at $6.42 1/2 per bushel, March wheat was 6 1/2 cents higher at $6.51 1/4 and January soybeans ended 1 1/2 cents lower at $11.98 1/4, according to Barchart.com.

• Chat more about the markets in Wednesday's Floor Talk
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The lower close for beans capped off a day that saw the nearby contract start out lower, then surge higher around mid-day. As has been the case the last few days, the South American weather situation drove much of Wednesday's price action. How that price action continues in the near and distant future is the subject of some disagreement among analysts and traders.

"IF (and it is a big 'if') weather remains inflammatory into January and February for South America, I can make a case for the 'highs' to be in for '2012,' as sharply higher prices now will only encourage even more production and in some cases reduced demand in the Northern Hemisphere," said Jim Bower of Bower Trading, Inc., in Chicago in a newsletter to his customers on Wednesday morning.

But, don't count out higher prices just yet, based simply on the progress of the South American crops and how their development may unfold as a result of the hot, dry La Nina weather conditions.

""It's the realization that corn is hurting a lot worse in South America right now than soybeans," says AgTraderTalk.com market analyst and trader Kevin Penner. "Corn is pollinating and there's still really another month before heat will jack up the beans."