Soybeans rose the most in more than a week and corn gained for the first time in three sessions as adverse weather threatens to reduce crop yields in South America. Dry weather in the next 10 days will reduce soil moisture and increase stress on crops in parts of Argentina, Paraguay and Brazil, T-Storm Weather LLC said in a report. About 40 percent of the growing area has been drier than normal since Nov. 15 in Brazil, which the U.S. government ranks as the biggest global shipper of soybeans this year. “After a fast start to planting crops in the last two months, the drier weather is becoming a concern,� Greg Grow, the director of agribusiness for Archer Financial Services Inc. in Chicago, said in a telephone interview. “People have been betting on record or near-record production in South America, and that is now coming into question.� Soybean futures for January delivery gained 0.6 percent to close at $11.185 a bushel at 1:15 p.m. on the Chicago Board of Trade, the biggest gain since Dec. 2. Yesterday, the price touched $10.95, the lowest for a most-active contract since October 2010. The oilseed has dropped 20 percent this year on rising world production and U.S. inventories. Corn futures for March delivery rose 0.1 percent to $5.945 a bushel. The grain has slumped 5.5 percent this year as rising global output reduced demand for U.S. supplies. Corn is the biggest U.S. crop, valued at $66.7 billion in 2010, followed by soybeans at $38.9 billion, government data show. To contact the reporter on this story: Jeff Wilson in Chicago at jwilson29@bloomberg.net To contact the editor responsible for this story: Patrick McKiernan at pmckiernan@bloomberg.net

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