Global agribusiness company Monsanto Co said on Wednesday that net income surged nearly 80 percent in the third quarter due to strong sales in its core seeds and genetic traits businesses.

Shares rose 3 percent in premarket trade as the market applauded the company's sales strength in the United States and Latin America. Total sales of Monsanto's specialized corn, soybean, cotton and other seeds and traits rose 12 percent to $2.6 billion in the quarter.

Monsanto, the world's largest seed company, said new corn and soybean products were well received by farmers this spring, helping push earnings for the third quarter ending May 31 to $680 million, up from $384 million in the same period a year earlier.

Earnings per share were $1.26, compared with 70 cents a share a year ago, or 81 cents a share on an ongoing basis. Analysts had expected $1.11.

The company raised its full-year earnings guidance, with full-year 2011 ongoing earnings now seen in the range of $2.84 to $2.88, up from $2.72-$2.82. Full-year 2011 EPS guidance on an as-reported basis is expected in the range of $2.82-$2.86, up from $2.66-$2.79.

Monsanto also said it was raising its expectations for free cash flow for 2011 to $1.1 billion-$1.3 billion from $900 million-$1.1 billion

The quarterly results were clouded partially by Monsanto's announcement that it was under investigation by the Securities and Exchange Commission regarding Monsanto's customer incentive programs related to its glyphosate products for fiscal years 2009 and 2010.

The company said investigators have subpoenaed documents related to the programs and company officials are cooperating.

Glyphosate, the key ingredient in Monsanto's Roundup herbicide, was once a key driver of revenues. But the company has been struggling with stiff competition and implementing programs as well as rolling out new products to try to boost sales even as it has shifted its focus to the seeds side of the company.

For this most recent quarter, the agricultural productivity segment, which includes herbicide products, saw sales rise 57 percent to $943 million. Segment earnings rose to 76 million from a loss a year ago of $175 million.

(Reporting by Carey Gillam, editing by Gerald E. McCormick, Dave Zimmerman)