U.S. agricultural processor Archer Daniels Midland Co said on Tuesday quarterly net earnings rose from a year ago, but its profits were squeezed by high corn costs and tight oilseed processing margins.

For the fiscal first quarter that ended September 30, Archer Daniels reported a net profit of $460 million, or 68 cents per share, up from $345 million, or 54 cents a share, in the same quarter a year ago.

Adjusted to exclude inventory gains and one-time items, earnings per share were 58 cents.

Revenue rose to $21.9 billion, from $16.8 billion in the year-ago quarter.

Decatur, Illinois-based ADM, the world's largest corn processor and among the largest ethanol producers in the United States, said soaring corn prices, which more than doubled from last year, dragged down profits in its corn processing segment.

The unit earned a net $179 million, down 48 percent from the same quarter a year earlier despite processing volumes rising 5 percent.

ADM blamed weak crushing margins for a 28 percent decline in oilseed processing profit, which fell to $221 million from $308 million a year earlier.

The company's agricultural services segment, which buys, sells, stores and ships farm products, rebounded from a poor first quarter last year due to the restart of grain exports from the Black Sea region after a drought-related hiatus.

Profit more than doubled to $244 million, from $112 million a year ago, despite lower grain export volumes from the United States.

ADM's other businesses, including cocoa processing and wheat milling, posted a net profit of $55 million, reversing a loss of $16 million a year ago.

Its shares closed on Monday at $28.94 on the New York Stock Exchange, down 4.6 percent.

(Reporting by Karl Plume in Chicago, editing by Gerald E. McCormick and Maureen Bavdek)