*

Corn rises on uptick in demand interest

*

Soy loses ground as South American crop looms

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Wheat gains support on questions over Russian export

volumes

(Updates to market close)

By Heather Schlitz

CHICAGO, Dec 16 (Reuters) - Chicago corn and soybean

futures seesawed on Monday as market players weighed an uptick

in fund buying interest against the prospect of a bumper South

American corn and soy crop, traders said.

Wheat futures fell on weakened export demand, though a hefty

wheat purchase by Saudi Arabia and the Russian government's move

to slow export sales supported the market.

"There's decent demand for corn and beans, and managed money

is buying corn and soy," Jim Gerlach, president of A/C Trading,

said.

Chicago Board of Trade corn settled up 3 cents at

$4.45 a bushel.

Soybeans ended down 6-1/4 cents at $9.82 a bushel

after the National Oilseed Processors Association reported the

U.S. crush declined in November from an all-time high a month

earlier and fell short of most trade estimates.

However, losses in soybeans were limited as the crush was

still the largest November on record and fourth-largest for any

month.

Favorable South American crop conditions and a lack of

weather threats have pressured corn and soy futures, though both

have received support from bargain buying after price falls late

last week.

Corn last week touched its highest level since June after

the U.S. Department of Agriculture cut its estimate for U.S.

end-of-season stocks, but disappointing U.S. corn and soybean

export sales last week caused price weakness on Thursday and

Friday.

Chicago Board of Trade most-active wheat settled down

2-1/4 cents at $5.50 a bushel.

Saudi Arabia purchased 804,000 metric tons of wheat on

Monday, well above the 595,000 tons it sought in the tender.

Though the U.S. is not expected to supply the wheat, a large

purchase takes a hefty chunk of the grain out of the market,

traders said.

"The purchase gave the market a bit of a boost," Austin

Schroeder, analyst at Brugler Marketing, said.