CHICAGO, Oct 1 (Reuters) - JPMorgan cut its full-year earnings estimate for Archer Daniels Midland Co to$2.29 per share, down from $2.69, in anticipation of lower earnings from biodiesel and lower ethanol prices, the brokerage said on Monday.

JP Morgan maintained its rating of “overweight,” believing that infrastructure investments will boost ethanol demand and improve ethanol economics, said analyst Pablo Zuanic.

ADM shares were up 17 cents, or 0.51 percent, in early morning trading on the New York Stock Exchange. So far this year, ADM’s stock has risen about 4 percent. Its 2008 fiscalyear ends June 30.

ADM is the second largest U.S. ethanol producer behind privately held POET. ADM has 1.070 billion gallons of ethanol capacity with 550 million gallons under construction.

Record corn costs and soft ethanol prices have combined to squeeze the profitability of U.S. biofuel producers and no respite is in sight, analysts said.

U.S. corn futures traded at $3.72-3/4 per bushel on Monday, up more than 35 percent from lows near $2.74 in October 2006. Ethanol prices, meanwhile, are down nearly 40 percent from this year’s peaks