GRAINS-Soybeans hit 1-week low as market readies for USDA report

* Soybeans extend losses into third straight session

* USDA expected to cut estimate for soybeans from Argentina

* Corn falls, wheat firms

SYDNEY, March 8 (Reuters) - U.S. soybeans edged lower on Thursday to hit a one-week low, as traders readied for a widely watched U.S. Department of Agriculture report that is expected to confirm lower production from Argentina, one of the world's largest exporters. Wheat edged higher, rebounding from losses of 2 percent in the previous session, while corn fell. The most active soybean futures on the Chicago Board of Trade were down 0.3 percent at $10.62-3/4 a bushel by 0310 GMT. They earlier fell to their weakest since March 1 at $10.62-1/4 a bushel, after closing down 0.9 percent on Wednesday. Analysts attributed the loss to a degree of caution ahead of the latest USDA supply and demand report later in the session. "The market's main focus will be on how much the USDA cuts the estimate of Argentina's soybean crop," said Tobin Gorey, director of agricultural strategy at Commonwealth Bank of Australia. The market expects the USDA to cut its estimate for Argentina soybean production to 48.36 million tonnes, a Reuters poll showed. The loss to world supply is likely to be partially offset by higher production in Brazil. The USDA forecast comes as rains are forecast across Argentina, though traders said the moisture is likely too late to save yields. The most active corn futures were down 0.3 percent at $3.86-1/4 a bushel, having ended the last session 0.3 percent lower. The most active wheat futures were up 0.2 percent at $4.98-1/4 a bushel, after closing Wednesday down nearly 2 percent. The USDA is expected to forecast larger U.S. wheat ending stocks, due in part to weak export demand, and slightly smaller domestic stockpiles of corn, according to analyst polls by Reuters.

Grains prices at 0310 GMT

Contract Last Change Pct chg Two-day chg MA 30 RSI CBOT wheat 498.25 1.00 +0.20% -1.73% 474.47 63 CBOT corn 386.25 -1.00 -0.26% -0.52% 374.88 71 CBOT soy 1062.75 -2.50 -0.23% -1.12% 1028.3 61


CBOT rice 12.49 $0.00 +0.00% +0.12% $12.45 61 WTI crude 61.29 $0.14 +0.23% -2.09% $62.59 40


Euro/dlr $1.240 -$0.001 -0.09% -0.01% USD/AUD 0.7827 0.000 +0.05% +0.00%

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

(Reporting by Colin Packham; Editing by Biju Dwarakanath)