US wheat and corn fell for the second day on Tuesday and soya hit a 3-week low, pressured by fresh eurozone fears after Greece's call for a referendum on its bailout package as well as a panicky reaction to futures trader MF Global's bankruptcy fallout.
The dollar soared nearly 2 percent, crude oil fell almost 3 percent and the Dow stock market index plunged over 2 percent as Greek government faced possible collapse on Tuesday.
At 11:30 am CDT (1630 GMT), Chicago Board of Trade December wheat was down 7 cents per bushel at $6.20-1/4, December corn was down 6-1/2 at $6.40-1/2 and January soyabeans were down 21 at $11.96-1/4. Dealers continued to monitor news on MF Global. Trading in Australian grain futures and options was suspended on bourse operator ASX Ltd's futures platform following the collapse of MF Global.