Deere & Co. posted higher-than-expected earnings this morning, sending its shares up more than 8 percent as wider margins at its farm equipment and finance units helped it overcome weak economic conditions, Reuters reported.

Deere, the world’s largest maker of agricultural equipment, reported a net profit of $243.2 million, or 57 cents a share for its first fiscal quarter, which ended Jan. 31. That’s up from $203.9 million, or 48 cents a share, a year earlier. Revenue fell 6 percent to $4.84 billion. Analysts, on average, expected the Moline, Ill.-based company to earn 19 cents a share on sales of $4.12 billion, according to Thomson Reuters. Net income at the company’s financial services arm nearly doubled to $85.1 million, from $46.8 million last year, as the spread between Deere’s borrowing costs and the interest it charges customers widened.

The company also raised its outlook for fiscal 2010 machinery sales growth to a range of 6 percent to 8 percent, from a previous estimate that sales would fall 1 percent.

Profitability in the unit that makes Deere’s tractors and harvesters was especially impressive, reporting margins of nearly 10 percent — three times what investors had expected, according to Eli Lustgarten, an analyst at Longbow Securities.

“It looks like brilliant profitability in ag in a relatively weak market,” Lustgarten said. “It’s a combination of restructuring, it’s a combination of operating efficiency, it’s execution, and brilliant ag margins.”