Wheat futures rose on short-covering and worries about drought in Australia, and corn followed wheat higher, shrugging off pressure from bearish weekly US ethanol statistics.
As of 12:46 p.m. CDT (1746 GMT), Chicago Board of Trade November soybeans were down 16 cents at $8.59-1/2 per bushel after dipping to $8.58-1/4, a one-week low.
CBOT December wheat was up 5-1/4 cents at $4.66 a bushel and December corn was up 2 cents at $3.60-1/2 a bushel.
Soybeans firmed in early moves on news that China and the United States agreed to hold high-level talks in early October, raising hopes for a thaw in their trade dispute. China is the world's top soy importer.
But CBOT soy futures turned lower as brokers shifted their focus to ample US supplies and prospects for large harvests in South America, which has ramped up exports to China during the trade war.
Commodity brokerage INTL FCStone late Wednesday raised its forecast of the US 2019 soybean yield to 48.3 bushels per acre, from its Aug. 1 figure of 47.2.
The firm put US soybean production at 3.661 billion bushels, down from 3.743 billion previously, reflecting a smaller harvested acreage figure from last month.
On Thursday, INTL FCStone projected Brazil's 2019/20 soybean crop at 121.41 million tonnes, up from 115.07 million in 2018/19.
The US Department of Agriculture has projected Brazil's 2019/20 crop at 123 million tonnes.
"Without an agreement with China to buy our beans, they (China) are free to buy South American soybeans.
And that is going to hurt our export demand," said Brian Hoops, president of broker Midwest Market Solutions.
Separately, China's customs agency said it has allowed imports of soymeal and other oilseed products from Russia, which so far has been a minor soybean producer.
"We continue to lose market share. And this trade deal between us and China is nowhere close to happening," said Tom Fritz, a partner with EFG Group in Chicago.
CBOT wheat futures climbed, rallying from three-month lows set this week, while K.C. hard red winter wheat futures and Minneapolis Grain Exchange spring wheat futures recovered from 14- and 10-year lows, respectively.
Traders cited wheat prospects in Australia, which is struggling with a third straight year of drought.
"There are concerns about the crop in Australia being hurt, and that could show up in the USDA report next week," said Hoops, referring to the USDA's monthly supply/demand report due on Sept. 12.
Corn futures inched higher as the strength in wheat helped lift corn from life-of-contract lows set a day earlier.
Traders shrugged off bearish weekly ethanol data. The US Energy Information Administration said weekly US output of the corn-based biofuel fell to 1.01 million barrels per day, the lowest since April, while stocks rose to 23.8 million barrels.