GRAINS-Wheat up for 3rd day on short-covering, USDA supply forecast

* USDA trims world wheat ending stocks forecast for 2017/18

* Chicago soybean, corn futures rise on bargain-buying

(Adds comment, detail) SINGAPORE, Sept 14 (Reuters) - Chicago wheat futures rose for a third consecutive session on Thursday, with prices underpinned by short-covering and U.S. government forecasts of slightly lower global supplies. Soybeans edged higher, although gains were checked by the U.S. Department of Agriculture's (USDA) outlook for record-sized North American production. The Chicago Board of Trade most-active wheat contract had added 0.3 percent to $4.44-1/2 a bushel by 0322 GMT, having closed up 0.3 percent on Wednesday. Soybean prices were up 0.5 percent at $9.65 a bushel, after firming 1.1 percent in the last session. Corn gained 0.6 percent to $3.53-1/2 a bushel, having closed unchanged on Wednesday. "When you look at wheat prices, we have to see what funds are doing," said a Singapore-based trader. "The USDA has reduced its supply estimate, but there is still plenty of wheat around, we don't see this price move as very significant." Commodity funds were net buyers of CBOT wheat for a second day in a row on Wednesday. They were net buyers in soybean futures and net sellers of corn contracts, traders said.

The USDA in its monthly supply-demand report trimmed world wheat ending stocks forecast for 2017/18 to 263.14 million tonnes, from 264.69 million in August. In signs of abundant supplies, French soft wheat exports outside the European Union could more than double in 2017/18 from last season when they plunged after a poor harvest in the EU's largest wheat producer, farm office FranceAgriMer said.

Soybeans were under pressure from the USDA's forecast on Tuesday for a record-large U.S. 2017 soybean harvest totalling 4.431 billion bushels, with an average yield of 49.9 bushels per acre (bpa). The USDA said private exporters sold 167,370 tonnes of U.S. soybeans to Mexico for delivery in the 2017/18 marketing year that began Sept. 1. For corn, the farm department pegged U.S. yields at 169.9 bpa. The government's yield estimates for both crops were above most analyst estimates. The spotlight is now turning to South America where farmers will start planting corn and soybeans. Dry conditions could slow seeding in parts of Brazil, while excessive rains are threatening seedings in parts of Argentina.

Grains prices at 0322 GMT

Contract Last Change Pct chg Two-day chg MA 30 RSI CBOT wheat 444.50 1.25 +0.28% +0.57% 448.83 53 CBOT corn 353.50 2.00 +0.57% +0.57% 363.16 40 CBOT soy 965.00 4.50 +0.47% +1.53% 949.76 54 CBOT rice 12.85 -$0.06 -0.50% -0.81% $12.65 62 WTI crude 49.22 -$0.08 -0.16% +2.05% $48.10 61


Euro/dlr $1.188 -$0.001 -0.07% -0.74% USD/AUD 0.8005 0.002 +0.26% -0.16%

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

(Reporting by Naveen Thukral; Editing by Joseph Radford)