DECATUR, ILL. — Strong results from all business units and especially oilseeds and corn processing led to a 37% gain in earnings at Archer Daniels Midland Co. in the third quarter ended March 31. Net income in the third quarter was $578 million, equal to 86c per share on the common stock, up from $421 million, or 65c per share, in the third quarter of fiscal 2010. ADM said the $157 million increase reflected a $310 million pre-tax increase in segment operating profit, which was offset partially by changes in LIFO inventory valuations, caused by higher agricultural commodity prices.

Net sales were $20,077 million, up 33% from $15,145 million.

“The ADM team performed very well,” said Patricia A. Woertz, chairman and chief executive officer. “Against a backdrop of volatile commodity prices, a challenging margin environment and geopolitical instability in the Middle East, North Africa and Cote d’Ivoire, our team worked smart and hard and delivered strong results.

“As we look ahead, we are monitoring the planting and growing season in North America and Europe. Overall, global demand for crops and agricultural products remains relatively strong.”

Within its processing businesses, the widest improvement was in the Corn Processing operating segments. Operating profits were $204 million, up 96% from $104 million in the third quarter of fiscal 2010.

ADM said processed volumes were up 13%, reflecting increased production at the company’s corn processing plants, including two new ethanol dry mills.

The sweeteners and starches business accounted for $46 million of the $104 million profit in the quarter, but it was virtually flat year over year, as higher net corn costs mostly offset higher average selling prices and volumes. Export demand for sweetener remained strong, and U.S. demand for industrial starches improved.

Operating profit of the Oilseeds Processing segment was $512 million, up 26% from $405 million in the same quarter in the last fiscal year.

Crushing and origination operating profit increased $133 million to $405 million for the quarter. Favorable ownership and strong North American results offset a decline from South America, ADM said, while European results increased significantly, principally on the reversal of mark-to-market timing effects.

ADM’s Other segment, which includes flour milling and cocoa processing, had operating income of $119 million, up sharply from $22 million in the third quarter last year.

ADM said the increase reflected improved results from its wheat milling and cocoa operations, which rose $87 million year over year. During the third quarter, cocoa operations in the Ivory Coast were suspended, and ADM said it met customer needs through its global cocoa processing network.

Operating profit in the Agricultural Services segment rose 4% to $171 million.

For the nine months ended March 31, ADM net income was $1,655 million, or $2.55 per share, up 12% from $1,484 million, or $2.30 per share, in the same period a year ago. Sales were $57,806 million, up 26% from $45,979 million.