(Recasts, adds more details from report, background, analyst
comments; adds byline)

By Karl Plume

CHICAGO (Reuters) - U.S. grain exporters sold more
corn last week than in any other week in almost 16 years and
the most wheat in three years as a harsh drought in the Black
Sea region slashed grain shipments from several other
countries, traders and industry analysts said on Thursday.

Weekly combined sales of corn, wheat and soybeans, the
three biggest U.S. agricultural exports, were the largest in at
least two decades, according to U.S. Agricultural Department
data.

Several traders said the combined sales appeared to be the
largest ever for a single week. The USDA data base goes back to
1990.

<^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^

Graphic showing U.S. grain export sales:

http://link.reuters.com/bas95n

^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^>

A drought in the Black Sea region, which includes major
grain suppliers such as Russia and Ukraine, has slashed crop
production there and curtailed exports, sending importers
scrambling for supplies from United States and elsewhere.

Russia, the Black Sea region's top exporter, has banned
grain exports through at least the end of 2010 and analysts
said Thursday that the country may be forced to import as much
as 2.2 million tonnes of grain in the coming year due to the
worst drought on record.

"There was an awakening roused by the embargo news out of
Russia," said Bill Nelson, analyst with Doane Advisory
Services. "It was pretty clear to the grain markets that they
were having problems, and prices were moving up," he said.

But the embargo news "was what drove it to the front pages
and to the nightly news," Nelson added.

Ukraine, the world's top barley exporter and a major corn
and wheat exporter, also was expected to restrict grain
shipments with an export quota system.

RISING PRICES

Wheat prices have nearly doubled since July, helping lift
corn and soybean prices despite forecasts for record-large
crops to be harvested this fall.

"When prices started to rally because of the wheat market,
the overall commodities sector picked up that bullish market
sentiment and that brought buyers into the market," said Shawn
McCambridge, analyst with Prudential Bache Commodities.

Other buying incentives were a weaker dollar, which makes
U.S. grain cheaper overseas, and the belief that U.S. corn and
soybean yields may not meet government forecasts.

Corn export sales were bolstered mostly by large sales to
regular customers.

USDA said on Thursday that net corn sales in the week ended
Aug. 12 totaled nearly 2.9 million tonnes, the largest since
December 1994 when a single week's sales totaled nearly 3.3
million tonnes amid huge sales to China.

Top buyers last week were Japan, Mexico and Egypt with more
than half of the week's total. USDA also reported modest sales
to China and 738,600 tonnes to undisclosed destinations.

Net wheat export sales last week totaled 1.4 million
tonnes, up 6 percent from the previous week and the largest
since September 2007.

The largest buyer last week was Egypt, the world's top
wheat importer, which had been sourcing most of its wheat over
the past year from Russia.

U.S. wheat export sales in the current marketing year,
which began on June 1, are 56 percent higher than at the same
point last year.

Net soybean export sales last week totaled more than 2.2
million tonnes, down 14 percent from the prior week but near
the high end of trade forecasts.

Sales to China, the world's top soybean importer, accounted
for 57 percent of the week's sales. Egypt was also a big buyer,
with 200,000 tonnes in new-crop purchases.
(Reporting by Karl Plume; Editing by Walter Bagley)