U.S. soybeans rose on Wednesday on buying interest after falling 1.5 percent in the previous session but with gains limited by concern about slowing economic growth in China, the world's largest soybean importer.
Corn strengthened from a one-week low touched on Tuesday as harvesting of a near-record crop starts in the United States. Wheat rose for a second session on renewed buying after touching a near four-month low on Monday.
"We are seeing some light buying interest supporting soybeans, wheat and corn today after recent falls but the worry about China's economic growth is still hanging over the market," said Stefan Vogel, head of agricultural commodity markets research at Rabobank.
"I do not see any major new fundamental factors supporting markets today, there is some positioning taking place ahead of the U.S. Department of Agriculture's world supply and demand report on Sept. 11."
Chicago Board of Trade November soybeans were up 0.4 percent at $8.77-1/2 a bushel at 0846 GMT. December corn rose 0.2 percent to $3.69-3/4 a bushel, after falling 1.8 percent on Tuesday.
December wheat added 0.05 percent at $4.86-1/2 a bushel, having also risen on Tuesday from its Monday lows.
Soybeans ended a three-session winning streak on Tuesday, after a report that showed China's manufacturing sector contracted at its fastest pace in three years during August.
"There are still concerns about Chinese demand but exports of U.S. new-crop beans are improving, which is a supportive factor," said Kaname Gokon of brokerage Okato Shoji.
The U.S. Department of Agriculture on Monday said weekly soybean export inspections totalled 184,285 tonnes, near the high end of trade forecasts ranging from 100,000 to 200,000 tonnes.
"U.S. export sales for soybeans were good but currently Brazil and other South American suppliers are looking more competitive," Vogel said.
Commodity brokerage INTL FCStone on Tuesday raised its forecast for the U.S. 2015 corn harvest to 13.457 billion bushels from 13.381 billion in its previous monthly report.
INTL FCStone trimmed its forecast of U.S. 2015 soybean production to 3.791 billion bushels from its August forecast of 3.797 billion bushels.
The USDA's forecast of the U.S. harvests next week will be especially closely watched.
"Regardless of what the USDA says, uncertainly will remain in the market about the U.S. crops. We will have to wait until the harvesters have started widespread work to get a clearer picture of U.S. yields," Vogel said.