Corn As WPI readers are well aware, corn prices/basis have risen around the world due to strong demand, most notably Chinese purchases, and tightening supplies. During the past few days, however, world demand has slowed and premiums are reversing their higher trend. For South American origins, premiums seem to have collapsed in the past few days.  In Argentina, November/December corn was offered at 175Z a few weeks ago with bids at 165Z. This week offers are at 155Z with no bids in sight. For Brazil, December corn was offered at 200Z and it was hard to imagine a downside, but now offers stand at 185Z versus bids at 165Z.  Despite the 20-cent reduction in offer-side premiums, it seems that prices in Argentina did not fall as muc...