* Wheat rises on lower-than-expected U.S. crop rating

* Rains expected to benefit global wheat crops

* Traders watch China to buy more U.S. corn, soy

CHICAGO, Oct 27 (Reuters) - Chicago Board of Trade corn futures on Tuesday reached their highest in more than a year on strong export demand, while wheat prices firmed on concerns about crop conditions in the U.S. Plains, traders said.

Soybeans futures were near unchanged after hitting their highest price since July 2016 on Monday.

Traders eyed the condition of wheat crops after the U.S. Department of Agriculture, in a report issued after the markets closed on Monday, said that 41% of U.S. winter wheat was in good/excellent condition. That was below analysts' expectations of 52%.

Dryness has hampered wheat plantings in the U.S. Plains and other key countries such as Russia. However, precipitation is improving the outlook for the crops in producing areas, analysts said.

"We've got moisture ahead," said Don Roose, president of brokerage U.S. Commodities.

CBOT most-active wheat was up 3-1/2 cents at $6.23-1/2 a bushel at 1052 a.m. CDT (1552 GMT). Soybeans were down 1-1/2 cents at $10.82 a bushel. Corn was up 1/2 cent at $4.18-1/4 a bushel, after reaching a session high of $4.22-1/4, its highest price since August 2019.

Corn advanced following a flurry of tenders from countries such as South Korea, Taiwan and Iran.

"Corn is being supported by firm demand, with the U.S. the main supplier in the export market and expected to remain so until into 2021," said Matt Ammermann, StoneX commodity risk manager.

Traders are waiting to see whether China, the world's top soybean importer, buys more U.S. corn and soy following a recent uptick in purchases.

In Brazil, which competes with the United States for sales to China, soy farmers had planted 23% of their estimated crop by Thursday, according to agribusiness consultancy AgRural.

Rain should help Brazilian soybean planting, Ammermann said.

"Soybeans have been supported by demand from China for U.S. beans, and an improved crop outlook in Brazil would give China more buying options," he said. (Reporting by Tom Polansek in Chicago; Additional reporting by Michael Hogan in Hamburg and Naveen Thukral in Singapore; Editing by Jan Harvey and David Evans)