CBOT soybeans end lower for third straight session

CHICAGO, March 11 (Reuters) - Chicago Board of Trade soybean futures ended lower on Tuesday for a third straight session, coming under pressure from hefty South American supplies hitting the global market, weakness in the soyoil market and uncertainty over how U.S. tariffs will impact domestic demand, traders said.

• In its monthly supply-and-demand report Tuesday, USDA kept its estimate for U.S. soy stocks unchanged at 380 million bushels, compared to analysts' expectations of 379 million bushels.

• CBOT May soybeans SK25 settled down 2-3/4 cents at $10.11-1/4 per bushel.

• CBOT May soymeal SMK25 ended the day down 50 cents at $301.80 per short ton.

• CBOT May soyoil BOK25 fell 0.33-cent to finish at 41.93 cents per pound.

• Weakness in the canola market RSK5 weighed on soyoil prices, traders said.

• Early in the session, and prior to the USDA release of World Agricultural Supply and Demand Estimates, CBOT's most-active soybean futures on a continuous chart Sv1 were up.

• USDA's monthly supply and demand data will not incorporate tariffs on Canada and Mexico until they take effect, the agency said. But Tuesday's data accounted for impacts of retaliatory tariffs imposed on the U.S. by Canada and China.

• China, the biggest soybean importer, retaliated against U.S. tariffs last week with hikes to import levies covering $21 billion worth of American agricultural and food products.

• Brazil soy exports in March are forecast to be far higher than previously predicted, ANEC reported Tuesday.

• In Brazil, the world's top soybean supplier, drought lowered production forecasts in Rio Grande do Sul state, local crop agency Emater said.