GRAINS-Corn and soy retreat from rally on profit-taking, US tariff fears

Updates for market open, adds bullets, changes byline; previous dateline CANBERRA/PARIS

By Heather Schlitz

CHICAGO, Jan 30 (Reuters) - Chicago Board of Trade corn and soy futures fell on Thursday as traders booked profits following recent rallies and ahead of the weekend, when U.S. President Donald Trump says he will impose tariffs on imports from Canada and Mexico, traders said.

Corn touched a 15-month high and soy hovered near a six-month high during the previous session, when hot, dry weather in Argentina's corn and soy belts rekindled global supply concerns.

"We've had a really big run up, and it's end-of-month profit taking going into the weekend," said Sherman Newlin, broker at Risk Management Commodities.

Most-active Chicago Board of Trade corn futures Cv1 were down 6 cents at $4.91 a bushel as of 1715 GMT (11:15 am CST), while CBOT soybeans Sv1 fell 17-3/4 cents to $10.43 a bushel.

Disappointing rainfall in Argentina and a dry outlook for the following weeks in Argentina are likely to continue supporting corn and soy futures.

"The picture is quite dire for corn and soybean development," said Isaac Hankes, research specialist at LSEG Data and Analytics.

Traders are waiting to see whether Trump will follow through on threats to impose tariffs against Mexico and Canada, which would likely spark retaliation from two of the largest U.S. crop importers.

"We're getting close to the Saturday tariff implementation with Mexico and Canada, and that's bringing uncertainty into the market," said Jim Gerlach, president of A/C Trading. "People are getting out ahead of that and seeing where the dust settles."

Weekly U.S. soybean export sales came below analysts' expectations.

In wheat, futures rose on reduced forecasts for Russian exports and fears that frigid weather may have damaged the U.S. winter wheat crop.

Consultancy Sovecon said on Thursday it had revised down its Russian wheat export forecast for 2024/2025 to 42.8 million tons from 43.7 million.

The most-active CBOT wheat contract Wv1 was up 3-3/4 cents to $5.66-1/2 a bushel.