GRAINS-Soybeans edge lower, set for biggest weekly rally in 5 weeks

* Soybeans draw support from strong U.S. exports

* Corn on course for fifth straight weekly slide

* Wheat set for sixth weekly fall in seven weeks

SYDNEY, Aug 25 (Reuters) - U.S. soybeans edged lower on Friday, although the oilseed was poised to record its first weekly gain in more than a month as strong export demand provided support. Corn eased, with the grain on course to finish the week down 3 percent, its fifth consecutive weekly decline, while wheat was on track for a weekly fall. The most active soybean futures on the Chicago Board Of Trade were down 0.2 percent at $9.44-1/2 a bushel at 0351 GMT after closing up 0.9 percent in the previous session. Buoyed by strong export demand, soybeans were up more than 0.5 percent for the week, the first weekly gain since July 21. "The export demand has provided some support but I think without some weather concerns potentially damaging the crop, it is hard to see this rally being extended," said Phin Ziebell, agribusiness economist, National Australia Bank. Weekly U.S. soybean export sales of more than 2 million tonnes for the shipping season that starts on Sept. 1 topped analyst estimates of 400,000 to 600,000 tonnes, U.S. Department of Agriculture (USDA) data showed. More than half of the sales were bound for China., Analysts also noted the threat of Hurricane Harvey rainfall that could hamper vessel loadings at the Gulf. The most active wheat futures were up 0.4 percent to $4.36 a bushel after closing up 0.7 percent in the previous session. Wheat is down nearly 1.5 percent for the week after closing up 0.7 percent last week. The most active corn futures were down 0.4 percent to $3.55 a bushel after closing down 0.1 percent on Thursday. Corn is down nearly 3 percent for the week, the fifth consecutive weekly fall as ample global supplies pushed prices to a near five-month low on Thursday. Iowa corn yields are projected to fall about 4.5 percent from last year's bumper crop, scouts on an annual tour said on Thursday after surveying 452 fields across the top U.S. corn-producing state.

Grains prices at 0351 GMT

Contract Last Change Pct chg Two-day chg MA 30 RSI CBOT wheat 436.00 1.50 +0.35% +1.40% 481.22 27 CBOT corn 355.00 -1.25 -0.35% -0.21% 378.03 20 CBOT soy 944.50 -2.00 -0.21% +0.69% 970.70 48 CBOT rice 12.65 -$0.03 -0.20% +0.40% $12.51 65 WTI crude 47.77 $0.34 +0.72% -1.32% $48.10 49


Euro/dlr $1.180 $0.000 +0.00% -0.07% USD/AUD 0.7899 0.000 -0.01% -0.04%

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

(Reporting by Colin Packham; Editing by Richard Pullin)