Wheat also gained on bargain-buying after also falling steeply this week due to the previous weakness in corn and supply pressure from US and European wheat harvests.

Traders pondered whether a call on Thursday between senior US and Chinese officials would herald progress in ending a trade dispute that has stalled US soybean exports.

They also looked to expected cooler temperatures early next week as a heat wave descended on much of the Midwest.

"I think there some short-covering might be going on," said Brian Basting, analyst with Advance Trading. "The forecast gets extremely important for soybeans at the end of July."

Investor sentiment was buoyed too by growing expectations that the US central bank will cut interest rates later this month.

September corn futures Chicago Board Of Trade (CBOT) were up 5-1/2 cents, or 1.2pc at $4.30 a bushel by 11:31 a.m. (1631 GMT), after holding above Thursday's two-week low of $4.28.

August CBOT soybean futures were up 22-3/4, or 2.5pc cents at $9.04 a bushel, wheat was also up 12-1/2, or 2.9pc cents to $5.06 a bushel.

Last week, grain markets were underpinned by fears that US corn and soybeans, already weakened by soggy planting conditions, could suffer from prolonged hot and dry weather.

But rain this week in the Midwest and forecasts for heat to ease next week created selling pressure this week.

"Normally we can expect some stability after the 4th of July," said Joe Vaclavik, president of Standard Grain. "But the hot and dry weather isn't as good of a sign as it normally is."

Investors are already looking ahead to a US Department of Agriculture (USDA) crop report on Aug. 12, which is expected to include updated planting estimates, for a clearer indication of harvest prospects.

"That's the next big data point," said Vaclavik. "We'll be able to get a slightly more accurate yield reading at that point."