GRAINS-Soy, corn futures rise on weak dollar, South America crop concerns

Adds U.S. market activity

By Tom Polansek

CHICAGO, Feb 20 (Reuters) - Chicago Board of Trade corn and soybeans rose on Thursday, recouping losses from the previous session with support from a weaker dollar and lingering concerns about poor crop weather in South America.

A fall in the dollar index =USD underscored favourable export prospects for U.S. corn, which fuelled a recent rally along with doubts over South America's harvest outlook.

A shortfall in South American crop production in the coming months could reinforce export demand for U.S. corn, analysts said.

The International Grains Council cut its forecast for 2024-25 global corn production , largely reflecting a diminished outlook for crops in Brazil and Argentina.

Heat is returning to Argentina's grains belt , according to the Buenos Aires Grains Exchange, after hot and dry conditions hurt crops in January.

"We still have some concerns about Argentina," said Ted Seifreid, chief market strategist for Zaner Ag Hedge.

CBOT March corn futures CH25 were up 1-1/4 cents at $4.98-3/4 a bushel by 12:55 p.m. CST (1855 GMT). The market on Wednesday hit 16-month peak of $5.04-1/2 in the most-active contract Cv1, before prices retreated.

CBOT March soybeans SH25 rose 9-3/4 cents to $10.41-1/2 a bushel, while March wheat WH25 fell 7-1/4 cents to $5.84-3/4 a bushel.

Traders on Friday will review weekly U.S. grain and soy export sales data for signs that corn demand remains strong.

Analysts expect weekly 2024-25 U.S. export sales of 900,000 to 1.6 million metric tons for corn and 100,000 to 500,000 metric tons for soybeans, according to a Reuters poll.

U.S. President Donald Trump said on Wednesday that a trade deal with China, the world's biggest soybean importer, was possible, easing concerns among some grain traders worried about the risk for tit-for-tat tariffs to disrupt agricultural shipments.

Wall Street's main indexes fell , with the S&P 500 off record highs as the market assessed the latest tariff threats from Trump.