By Jesse Newman

CHICAGO--Soybean futures sank Thursday to a fresh one-month low as good weather in South America assuaged fears over crop shortfalls there. Wheat also fell while corn was mixed.

Soybean prices fell below the psychologically significant $10 a bushel mark, as rainfall in Argentina assuaged fears that dryness would hamper output in that country. Traders have been eyeing growing conditions in South America for signs that adverse weather there would take a toll on crop production, but rains overnight as well as forecasts for showers over the weekend lessened concerns that harvests would reduce by dry weather.

Solid export sales of the oilseeds failed to keep the market afloat, in part due to speculation over stiff export competition in the offing from Brazil. Karl Setzer of brokerage MaxYield Cooperative said Brazilian soybean exports in January could hit a record two million metric tons.

The U.S. Department of Agriculture said net soybean sales for the week ended Dec. 15 totaled about 1.8 million metric tons, toward the high end of analyst expectations.

Soybean futures for January dropped 12 1/4 cents, or 1.2%, to $9.94 1/2 a bushel at the Chicago Board of Trade, the lowest closing price since Nov. 18.

Wheat prices closed lower for the fifth out of six sessions, buffeted by abundant U.S. and global supplies of the crop. The world has the most wheat on hand ever, and domestic stockpiles are projected at a 29-year high next year. That is spurring concerns over U.S. export demand at the same time that weather improves in the U.S. wheat belt.

Weaker-than-expected export sales also pressured prices for the grain.

CBOT March wheat futures declined 2 1/2 cents, or 0.6%, to $3.97 a bushel.

CBOT March corn futures were flat. July-dated futures slipped 1/4 cent, or 0.1%, to $3.61 1/4 a bushel.

Write to Jesse Newman at jesse.newman@wsj.com

(END) Dow Jones Newswires

December 22, 2016 15:24 ET (20:24 GMT)

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