* Wheat on track to end week up 5 pct
* Black Sea tensions underpin gains
* Corn set for first weekly gain in seven weeks
By Colin Packham
SYDNEY, Aug 8 (Reuters) – U.S. wheat futures fell for a second session on Friday but the grain was poised to record its biggest weekly gain in five months as concerns over escalating tensions in Ukraine underpinned a rise of nearly 5 percent.
Corn fell but was set to finish the week in positive territory for the first time in seven weeks, while soybeans were set to record weekly gains of more than 1 percent.
Chicago Board of Trade September wheat futures fell 0.2 percent to $5.60-1/4 a bushel. Wheat fell for the first time in seven sessions on Thursday when prices closed down 1.1 percent.
Despite edging lower for two sessions, wheat is set to finish the week up almost 5 percent – the biggest weekly rise March 7.
“We’ve seen wheat rally strongly on short covering,” said Paul Deane, senior agricultural economist, ANZ Bank. “You would be pretty nervous if you were short wheat amid the rising tensions in the Black Sea region… we are seeing a bit of support withdrawn from the market.”
NATO said Russia has massed 20,000 troops at the border and may be planning to declare a humanitarian mission as an excuse to invade.
Meanwhile, light-to-moderate rains on Argentina’s Pampas grains belt slowed wheat sowing over the previous seven days, with 94.2 percent of the projected sowing area already planted, the Buenos Aires Grains Exchange said on Thursday.
December corn futures fell 0.4 percent to $3.69-3/4 a bushel, having closed down 0.8 percent.
Analysts said corn was continuing to come under pressure from the U.S. Agriculture Department export data, which pegged new-crop export sales of corn at 758,700 tonnes in the latest week, below trade estimates ranging from 800,000 to 1 million tonnes.
Despite edging lower, corn was set to finish the week up 2 percent, the first weekly gain in seven weeks, drawing support from the strength of wheat.
November soybeans were little changed at $10.77-1/2 a bushel, having closed down 0.19 percent on Thursday.
Soybeans is set to finish the week up 1.8 percent, the first weekly gain in three weeks.
Grains prices at 0232 GMT Contract
Change Pct chg Two-day chg MA 30 RSI CBOT wheat
547.29 64 CBOT corn
385.93 39 CBOT soy
1098.48 63 CBOT rice
$12.82 -$0.02 -0.16%
$13.33 34 WTI crude
$101.65 30 Currencies
$1.336 $0.000 +0.01%
0.925 -0.002 -0.20%
-1.09% 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)