* Corn falls from 14-month peak

* Wheat falls for third straight session

* Soybeans fall despite supply and demand concerns

* Wider market gloom on lockdown fears weighs

CHICAGO, Oct 28 (Reuters) - U.S. grain futures were trading in negative territory on Wednesday, correcting from recent highs, following a wider sell-off on global markets on concerns about the economic impact of a surge in COVID-19 infections in Europe and United States.

The most active corn futures on the Chicago Board Of Trade fell 11-1/2 cents to $4.04-1/2 a bushel as of 11:06 a.m. CDT (1606 GMT), after hitting a 14-month high of $4.22-1/4 a bushel Tuesday.

The most active soybean futures slid 14-1/4 cents to $10.62-1/4 a bushel, while CBOT wheat was down 6-3/4 cents at $6.09 a bushel.

"Corn and soybeans were trading at prices they were, based on assumptions of future developments," said Arlan Suderman, chief commodities economist at StoneX. "When you’re in a risk-off environment, like we are in the broader markets, that leaves them vulnerable."

Suderman said weather concerns for South America's soybean crop and hopes that China will buy more U.S. corn are fundamentally supportive, but those factors are not a sure bet.

"Corn and soybean prices were overbought and vulnerable to a correction," Suderman said.

Meanwhile, concerns of another COVID-19 shutdown in the United States threatens demand for corn-based ethanol, with usage trying to recover from the first lockdown.

"It looked like we might surpass a year ago," said Jason Ward, managing director of Northstar Commodity. "Then, in the last two weeks, we’ve seen a decline."

In wheat, recent moisture in the Black Sea Region has been spotty, but is enough to add pressure to the market.

"When you combine those showers with the soaking rains we’ve had in the southern plains, which will help, and you’re in a risk off environment, that combination’s going to make it hard for wheat," said Suderman. (Reporting by Christopher Walljasper; additional reporting by Colin Packham and Sybille de La Hamaide Editing by Marguerita Choy)