By Paulo Trevisani 



  -- Wheat for September delivery rose 1.3% to $5.34 1/4 a bushel on the Chicago Board of Trade on Wednesday as some traders expect China to buy the grain in the near future, despite tensions with the U.S. 


  -- Corn for December delivery rose 1.2% to $3.34 3/4 a bushel. 


  -- Soybeans for November delivery rose 0.3% to $8.95 1/4 a bushel. 


  HIGHLIGHTS 


  Feeding China's Livestock: Wheat led grain prices as traders expected China to buy old stocks of wheat and rice for livestock feed, AgResource said. Meanwhile, weather remains bad for wheat crops in parts of Russia, and Ukraine's stocks of the grain are at a 10-year low, both price-boosting factors. Short-covering also helped, AgResource says, warning that favorable crop conditions in the U.S. breadbasket will continue to prevent a rally. 


  "A trend reversal does not appear to be in the offing amid improved Central US weather," the broker says. 


  Weather Dampens Prices: Global demand for corn is in a positive trend, but supply remains too high to sustain a rally, said broker Marex Spectron. The firm said its metrics "suggests that a positive short-term demand shock continues to accumulate." 


  But the presence of crop-boosting weather conditions makes the surge in demand coincide "with the surge in supply." 


  Weak global credit markets add to downward pressure on prices, Marex says. "It remains to be determined which side of the S&D equation which will prevail." 


  INSIGHT 


  Dollar Not Weak Enough: A weak dollar could help U.S. food producers to export by giving importers more buying power, but despite the greenback's losses in the past few months there isn't indication that the exchange rate is having an impact, Dan Basse from AgResource said. He pointed out that currencies in key food producers, such as Argentina, Brazil and Russia, are also weak. That could prompt their farmers to produce more even if commodity prices, in dollars, weakened. The FX factor, however, "is something we are watching carefully," Mr. Basse said. If rival currencies strengthened, for example, U.S. farmers could get some tailwind. 


  Traders Glued to the Weather: Good weather for U.S. crops remains the driving force in markets, as traders worry that an oversupply will be hard to sell. 


  Jason Britt, from Central States Commodities, says demand "has been pretty good," while production, which is beefed up by good weather, is the problem. "The biggest thing continues to be weather ... we are working with big supplies," he says. The EIA is scheduled to release its weekly ethanol production report confirming potentially low demand for corn to make fuel. 


  AHEAD 


  -- The USDA is scheduled to release its weekly export sales at 8:30 a.m. EDT Thursday. 


  -- The USDA is due to release the monthly cattle-on-feed report at 3 p.m. EDT Friday. 


  -- The CFTC is scheduled to release its weekly commitments of traders report at 3:30 p.m. EDT Friday. 


  Write to Paulo Trevisani at paulo.trevisani@wsj.com