U.S. soybean futures rose 1.6 per cent on Monday due to technical buying after prices fell for four straight sessions last week to their lowest level since mid-November, traders said.
Corn and wheat also edged higher, with bargain buyers stepping into the market with prices near six-month lows.
"If nothing else, the market is oversold," Frank Cholly, a senior commodities broker at RJO Futures, said. "Fundamentally, nothing has really changed."
All three commodities closed last week in technically oversold territory according to the nine-day relative strength index.
Soybeans posted the day's biggest gains after drifting higher and lower during early trade. The wave of technical buying overcame early sluggishness keyed by the impending harvest in South American countries such as Argentina and Brazil.
Investors were reluctant to stake out big positions ahead of a U.S. Agriculture Department supply-and-demand report on Friday.
"Everyone knows they are oversold and due for some sort of bounce... (but) it seems like everyone's conviction is pretty low with the report on the horizon," said Jason Britt, president of Central States Commodities.
The report will provide the final update on 2012 U.S. crop production. Trading has been particularly volatile following the January supply-and-demand report, with corn making limit moves on the day of the release six times in a row.
Chicago Board of Trade (CBOT) March soft red winter wheat futures settled up four cents at $7.51-1/4 a bushel.
Short-covering provided further support to wheat prices. A U.S. Commodity Futures Trading Commission report issued on Friday afternoon showed speculators have built their largest bearish bet on CBOT wheat since mid-May.
CBOT March corn was up 5-1/4 cents at $6.85-1/2 a bushel, its biggest gain in percentage terms since Dec. 21, and CBOT March soybeans were 21-1/4 cents higher at $13.88-1/2 a bushel.
Soybeans found technical support after Friday's decline dropped prices for the March contract to $13.56, matching a mid-November low. Prices have not fallen below that level since June 28.
"We have seen a fair bit of liquidation in beans and now there is some end-user demand, which is resulting in a bounce," said Victor Thianpiriya, an agricultural strategist at ANZ in Singapore.
Investors in the soybean market are watching moves by buyers in China, the world's top importer, which has canceled U.S. cargoes in the last few weeks on an improved supply outlook in rival exporter Brazil.
Dry weather is expected in Argentina for the next seven days followed some light rain, said John Dee, a meteorologist for Global Weather Monitoring.
"Brazil should receive rains off and on for the next 10 days. All in all the forecast looks nearly ideal for South America," Dee said.
-- Mark Weinraub covers the grain futures markets for Reuters from Chicago. Additional reporting for Reuters by Sam Nelson.