By Jesse Newman

CHICAGO--Soybean futures rose Tuesday, bolstered in part by continued uncertainty over growing conditions in South America, a key U.S. rival.

Meanwhile, corn fell while wheat was mixed.

Soybean prices advanced for a second consecutive session amid forecasts for additional rainfall in Argentina, which traders fear will inhibit late planting of the crop in that country. Argentina is a major producer and exporter of the oilseeds, and crop shortfalls there can send foreign buyers in search of U.S. supplies instead, increasing demand and boosting the market.

Still, one analyst argued that while excess precipitation may prevent planting in some areas of the country, it could benefit crop yields in others, potentially mitigating the impact of adverse weather on harvests.

Soybean futures for January gained 9 cents, or 0.9%, to $10.05 1/2 a bushel at the Chicago Board of Trade.

Higher prices for soybean meal and soyoil, both products derived from soybeans, also supported prices for the oilseeds on Tuesday.

Corn prices eased after trading in a narrow range for much of the session. Grain traders are waiting for direction from a closely-watched crop report due out from the government on Thursday, in which the U.S. Department of Agriculture is likely to reduce its estimates for U.S. 2016 corn output as well as stockpiles next year.

"All these markets are still trading within fairly well-defined ranges that have been in place now for months," said Dave Marshall, farm-marketing adviser at TCFG LLC in Nashville, Ill.

CBOT March corn slid 1 3/4 cents, or 0.5%, to $3.58 1/4 a bushel.

Wheat prices closed both higher and lower, with nearby contracts weighed down by profit-taking after price for the grain hit a more than five-month high in the previous session. Analysts said buying by index funds propped up later-dated contracts, as funds this week are rebalancing their investment portfolios and bailing out of some bearish bets, which lifts the market.

CBOT March wheat futures shed 1/2 cent, or 0.1%, to $4.26 3/4 a bushel. July-dated futures ticked higher.

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

(END) Dow Jones Newswires

January 10, 2017 15:33 ET (20:33 GMT)

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