GRAINS-Soybeans slide to over 6-week low, face 3rd weekly fall

* Crude oil decline, ample supplies weigh on soybeans

* China's soy crush margins drop to weakest since Sept 2014

* Corn, wheat set to end the week lower

(Adds details, quotes) SINGAPORE, May 26 (Reuters) - Chicago soybean futures dropped to a more than six-week low on Friday and were poised for a third weekly fall as a deep fall in crude oil prices and plentiful world supplies put pressure on the oilseed. Corn and wheat were also set for weekly drop after rising marginally last week. The Chicago Board Of Trade most-active soybean contract has declined 1.8 percent so far this week, the biggest weekly loss in two months. Soybeans hit a low of $9.36 a bushel on Friday, the weakest since April 11. Corn has shed about 1 percent this week, the biggest weekly fall since April 21, and wheat has lost 1 percent for the week after closing 0.6 percent higher last week. Soyoil made from soybeans is a feedstock for making biodiesel and demand for the alternative fuel eases when oil prices decline. Oil markets remained weak on Friday after tumbling in the previous session when OPEC and allied producers extended output cuts but disappointed investors betting on longer or larger supply curbs. A record large output in South America is adding pressure on prices. "For many players the breakdown looks like the market finally succumbing to the addition of huge South American soybean crops to the market," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia. "Only persistently strong U.S. exports, which now look to be slowing, had forestalled the decline." There could be a slowdown in soybean imports by China, the world's biggest buyer, as crushing margins fall. China's crushing margins for soybeans fell to the weakest since September 2014 this week as soymeal stocks rose to their highest since mid-2012 amid sluggish end-user demand, pulling down prices for the livestock feed. Soybean processors in the Shandong province, a key crushing hub in the country's east, are losing 292 yuan a tonne <JCI-SBMG-SHDNI>. The U.S. Agriculture Department reported weekly export sales of U.S. corn at 457,700 tonnes (old and new crop years combined), below a range of trade expectations. Still, the International Grains Council raised its forecast for global grains consumption for 2017/18 on Thursday, signaling a bigger drawdown of world stocks than previously expected. The IGC, in its monthly report, revised its global grains consumption estimate for 2017/18 up by 7 million tonnes to 2.086 billion tonnes, just below the 2.087 billion forecast for 2016/17.

Grains prices at 0304 GMT

Contract Last Change Pct chg Two-day chg MA 30 RSI CBOT wheat 430.75 0.00 +0.00% -0.40% 433.08 55 CBOT corn 369.00 -0.25 -0.07% -0.61% 369.45 53 CBOT soy 936.50 -3.00 -0.32% -1.24% 961.68 33 CBOT rice 10.86 -$0.07 -0.64% -1.76% $10.26 60 WTI crude 48.77 -$0.13 -0.27% -5.04% $49.03 42


Euro/dlr $1.120 -$0.001 -0.10% -0.17% USD/AUD 0.7429 -0.002 -0.31% -0.97%

Most active contracts Wheat, corn and soy US cents/bushel. Rice: USD per hundredweight RSI 14, exponential

(Reporting by Naveen Thukral; Editing by Subhranshu Sahu)