GRAINS-Corn and soy ease on crop progress, wheat steadies after slide

By Gus Trompiz, Naveen Thukral

PARIS/SINGAPORE, April 29 (Reuters) - Chicago corn and soybeans eased on Tuesday, with both markets facing pressure from advancing U.S. planting and favourable crop weather in South America.

Chicago wheat steadied after a sharp fall on Monday fuelled by beneficial rain for U.S. crops.

Grain traders were continuing to monitor developments in U.S. tariff policy. Investors took some comfort from news that U.S. President Donald Trump's administration said it planned to reduce the impact of auto tariffs, though a trade stand-off with top soybean importer China continued to cloud U.S. export prospects.

The most-active corn contract on the Chicago Board of Trade (CBOT) Cv1 was down 0.3% at $4.82 a bushel at 1120 GMT but it held above a 2/1/2 week low touched on Monday. CBOT soybeans Sv1 gave up 0.2% to $10.60-1/2 a bushel.

U.S. farmers had planted 24% of the corn crop as of Sunday, the U.S. Department of Agriculture (USDA) said, one percentage point behind analysts' average estimate but ahead of the five-year average of 22%.

In a weekly report released after Monday's market close, the USDA said soybean crop was 18% planted, ahead of both the five-year average of 12% and analysts' average estimate of 17%.

In South America, regular showers have eased drought that had threatened to hurt Brazil's main corn crop, known as safrinha, while in Argentina a dry spell is set to help corn and soybean harvesting after heavy rain.

"The safrinha crop is looking very good and that is reassuring the market," Maxence Devillers, analyst with Argus Media, said.

While there was ongoing uncertainty over U.S. trade with China, expectations that Washington and Beijing will eventually lower tariffs through negotiations was helping underpin soybean prices, he added.

CBOT wheat Wv1 added 0.7% to $5.34-1/2 a bushel. The benchmark had dropped about 2.5% on Monday when it hit a three-week low, while individual delivery months sank to contract lows.

In its crop progress report, the USDA rated 49% on the nation's winter wheat crop as being in good or excellent condition, up from 45% a week ago and above expectations of 47%.

More rain is expected in the southern U.S. Plains in the week ahead, which could further ease drought and help crops in important growth stages.

Traders were monitoring a cold spell in Russia, though a recovery in Russian export volumes this month and U.S.-led efforts to end Russia's war with Ukraine were tempering supply concerns, traders said.