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Corn curbed by expected higher planting estimate in USDA report

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Weak exports, rain relief pressure wheat prices

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Soybeans ease after gains fuelled by soy oil rally

(Updates throughout for changes in U.S. trading, adds closing prices, adds analyst quote)

By P.J. Huffstutter

CHICAGO, March 28 (Reuters) -

Chicago Board of Trade corn futures on Friday slumped to the lowest price in more than three months on expectations of increased U.S. planting this year, before rebounding on a spate of fundamental trading and bargain-buying, market analysts said.

Soybeans also fell for most of the session under pressured from a bumper Brazilian soybean crop, before ending higher on potential domestic demand after the Trump administration asked

oil and biofuels producers

to hash out a deal on the next phase of the nation's biofuels.

"When you see these prices hit low enough, you'll see people value buying," said Angie Setzer, partner at Consus Ag Consulting.

Meanwhile, wheat futures hit a nearly eight-month low as traders focused on sluggish exports and rain relief in parts of the U.S. Plains.

Like other commodities, grain markets for much of the day were subdued ahead of broad tariffs promised by U.S. President Donald Trump from April 2, as well as proposed U.S. port fees on Chinese-built vessels.

But traders also spent much of the day adjusting their positions ahead of Monday's U.S. Department of Agriculture's planting report. It will be issued with quarterly estimates of U.S. grain stocks, in one of the most closely watched data releases of the year for grain markets.

U.S. farmers will plant 94.361 million acres with corn this year, up from 90.594 million in 2024, according to an average of analysts polled by Reuters before the USDA publication.

The most-active CBOT corn contract settled up 3-1/4 cents at $4.53-1/4 a bushel, after earlier reaching its lowest since December 20 at $4.42 a bushel.

CBOT soybeans ended 6-1/4 cents higher at $10.23 per bushel. Wheat closed down 3-3/4 cents at $5.28-1/4 a bushel, after earlier touching the lowest price since July 31.

Forecast rain for U.S. and Russian wheat belts and a low volume of U.S. wheat export sales reported on Thursday also pushed wheat futures lower.

And a U.S.-backed deal this week aimed at a ceasefire in the Black Sea has also weighed on wheat markets, increasing the prospects of smoother exports from Russia and Ukraine. (Additional reporting by Gus Trompiz in Paris and Naveen Thukral in Singapore; Editing by Rashmi Aich, David Evans and Aurora Ellis)