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COVID-19 lockdowns in China hang over commodity markets

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Dollar jump also curbs U.S. grain futures

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Money managers slash long position in CBOT corn

CHICAGO, Nov 21 (Reuters) - Chicago Board of Trade grain futures eased on Monday as a stronger dollar made U.S. commodities look less attractive to importers and traders worried that rising COVID-19 cases in China could dent its commodity demand.

The dollar advanced against most major currencies as China's fresh COVID-19 curbs fuelled worries over the global economic outlook. Beijing warned it was facing its most severe test of the COVID-19 pandemic.

"Corn futures gapped lower as exports continue to be a concern, elevated today by the dollar index gaining," CHS Hedging said in a note.

The most-active CBOT wheat contract was down 4 cents at $8.18 a bushel by 11:10 a.m. CST (1730 GMT), while corn fell 3-1/2 cents to $6.66-1/2 a bushel. Soybeans, meanwhile, were up 4-3/4 cents at $14.33 a bushel.

Crude oil and share prices also fell

"The increase is COVID-19 cases in China is seen as a bearish demand factor for food and energy consumption," market research firm Hightower said in a report.

The stronger dollar underscored a lack of competitiveness for U.S. wheat as Russian exports pick up and a 120-day extension to a grain shipping corridor from Ukraine is set to maintain flows from the war-torn country, analysts said.

Wheat prices in Russia, the world's biggest exporter of the grain, fell last week amid an extension of the Black Sea deal allowing Ukrainian grain shipments, analysts said.

In other news, traders said they were surprised by data issued on Friday that showed funds had reduced their long positions, or bets that prices would rise, in CBOT corn. The decline signals that the fund managers may see little reason to be long corn at this point, brokers said.

Data from the U.S. Commodity Futures Trading Commission showed money managers through Nov. 15 slashed their net long in CBOT corn futures and options to their least bullish stance since mid-August. (Reporting by Tom Polansek in Chicago, Gus Trompiz in Paris and Naveen Thukral in Singapore; Editing by Rashmi Aich, Chizu Nomiyama and Grant McCool)