GRAINS-U.S. wheat, corn, soy edge up on supply concerns

* Wheat gains for third day, market eyes Russia
* USDA to update crop estimates on Wednesday
* China's August soy imports fall by quarter

(Adds analyst, updates prices)
By Naveen Thukral and Ivana Sekularac
AMSTERDAM/SINGAPORE, Sept 10 (Reuters) - Chicago Board of Trade wheat, corn
and soy futures edged up on Monday on supply concerns as the market waited for
the U.S. government supply-demand report on Wednesday which could provide an
insight into whether the price rally to record highs this summer will continue.
Wheat rose for a third straight session on expectations Russia, the world's
fourth largest exporter, would soon announce export curbs and as adverse weather
hit crops in Australia, the No. 2 supplier.
"I think people are generally waiting on the sidelines for the (USDA) report
on Wednesday," said Erin FitzPatrick, Rabobank analyst.
"We do expect to see production downgrades, for the Black Sea region and for
Australia."
Chicago Board of Trade new-crop November soy was up 0.2 percent to
$17.39-3/4 a bushel by 1026 GMT, while December wheat added 0.75 percent
to $9.11-1/2 a bushel. December corn gave up 0.69 percent to $8.05 a
bushel.
In Europe, benchmark November milling wheat on the Paris-based
futures market was up one euro or 0.38 percent at 266 euros a tonne, on supply
concerns.
The U.S. Department of Agriculture report will update crop damage from the
worst drought in half a century, and could also help settle debate over whether
rainfall last month helped the soybean crop.
"We believe that a reduction in the crop forecasts for corn and soybeans to
10.4 billion bushels and 2.6 billion bushels respectively is already priced in,"
Germany's Commerzbank said in a daily note.
"If, however, the USDA assesses the soybean situation as being actually
somewhat better following recent rainfall and chooses not to revise its forecast
further downwards, this could weigh on prices."
The market is factoring in lower soybean imports by China, the world's top
importer. China imported 4.42 million tonnes of soybeans in August, the lowest
monthly level in 6 months, as record-high prices and reduced global supplies cut
demand.

BIG IN BRAZIL
A lower-than-expected U.S. production forecast from closely followed
analytical firm Informa Economics lifted soybeans from early lows on Friday, but
the market has remained under pressure ahead of the USDA report. It cut its soy
crop forecast by 5 percent to 2.639 billion bushels.
Private analysts on average expected the USDA to trim its crop forecast to
2.657 billion bushels from 2.692 billion in August, although some expected a
slight increase because of rains in recent weeks across northern and eastern
Midwest.
"Informa's September yield estimate has been very close to the USDA's
forecast, people see it as quite reliable," said Brett Cooper, a senior manager
of markets at FCStone Australia.
There are early forecasts of record-sized soybean output in Brazil, the
world's second largest exporter, with record prices encouraging farmers to plant
more.
"Some private forecasters are coming out with estimates of the largest-ever
South American soybean crop," Cooper said.
CBOT soybeans set a record high of $17.94-3/4 on Sept 4 and were firmly on
the uptrend until brokerage INTL FCStone on Thursday raised its soybean yield
estimate to 36.7 bushels per acre from its August forecast of 36.2
bushels.
The wheat market has been supported by speculation of a likely cut in
Russian exports while dry weather in Australia and a dry pattern in the southern
U.S. Plains wheat belt ahead of autumn planting added support.
"It will be very interesting to study the behaviour of Russian operators in
future tenders," French analyst Agritel said in a daily note.
"At the current pace of shipments, Russia would be unable to offer shipments
after mid-November. Ukraine will then take over but the volumes will also remain
limited to 5 million tonnes for the entire campaign."
CBOT corn futures hit a record high of $8.43-3/4 per bushel during
last month's USDA report, and prices have largely stagnated around the $8 level
since then waiting for fresh evidence of yield loss due to the drought.

* Prices as of 1040 GMT

Product Last Change Pct Move End 2011 Ytd Pct

Paris wheat 266.00 1.00 +0.38 195.25 36.24
London wheat 207.00 1.05 +0.51 153.65 34.72
Paris maize 255.25 0.00 +0.00 197.25 29.40
Paris rape 517.75 0.50 +0.10 421.50 22.84
CBOT wheat 884.75 0.00 +0.00 671.25 31.81
CBOT corn 798.75 3.75 +0.47 654.75 21.99
CBOT soybeans 1731.50 -0.25 -0.01 1207.75 43.37
Crude oil 96.36 -0.06 -0.06 98.83 -2.50
Euro/dlr 1.28 0.07 +5.51 1.30 -1.34
* All grain and oilseed prices for second position. Paris futures prices in
Euros per tonne, London wheat in pounds per tonne and CBOT in cents per bushel.

(Additional reporting by Valerie Parent in Paris, editing by William Hardy)