GRAINS-Soybeans ease before USDA data, canola slides on China anti-dumping duty

By Gus Trompiz and Naveen Thukral

PARIS/SINGAPORE, Aug 12 (Reuters) - Chicago soybeans eased on Tuesday, giving up some of their gains from the previous session as hopes of renewed demand from China cooled and the run-up to a U.S. government crop report put the focus back on large expected harvest.

In other oilseed markets, Canadian canola fell as much as 4% to a three-month low after China announced a steep import duty following an anti-dumping probe.

Corn and wheat also eased as traders adjusted positions before the monthly U.S. Department of Agriculture supply and demand report at 1600 GMT, expected to show plentiful U.S. and global supplies.

The most-active soybean contract on the Chicago Board of Trade (CBOT) Sv1 was down 1.3% at $9.98-1/2 a bushel to edge back below the $10 threshold crossed during Monday's 2.4% rally.

The day-earlier gains came after U.S. President Donald Trump urged China, the world's biggest soybean importer, to quadruple its purchases ahead of U.S. beans.

Washington and China later announced they were extending a tariff truce for a further 90 days but there no immediate agreements on agricultural trade.

"Trump's statement supported prices in the last session but reality is that U.S. is losing market share in China," said one oilseed trader in Singapore.

China has refrained from forward purchases of the upcoming U.S. crop, reinforcing Brazil's position as the main soybean supplier to China.

Heavy buying of Brazilian beans and tepid domestic demand have also led to hefty stocks of soymeal for livestock feed.

"There is no shortage of soybeans in China that would necessitate significantly higher purchases from the U.S.," Commerzbank said.

November canola futures RSX5 on ICE were down 3.9% at C$654.20 ($474.50) a metric ton, after falling to their lowest since May 7.

China on Tuesday announced a preliminary anti-dumping duty of 75.8% on Canadian canola imports, a fresh escalation in a year-long trade dispute that began with Ottawa's imposition of tariffs on Chinese electric vehicle imports.

Traders are watching to see if China opens its market to Australian canola, previously banned due to crop disease concerns, though they said it may be difficult to replace entirely Canadian crop, which dominates China's canola imports.

CBOT corn Cv1 lost 1.0% to $4.03-3/4 a bushel and wheat Wv1 shed 1.1% to $5.09-1/4 a bushel.

Condition ratings for U.S. corn and soybean crops eased in a weekly USDA report on Monday, in line with market expectations, but the corn score remained at a nine-year high.

($1 = 1.3787 Canadian dollars)