Monsanto said it has bought Agroeste Sementes for just over $100m, financing the transaction in cash.
The acquisition includes all of Agroeste's businesses, as well as the firm's corn seed brands, which currently make up 10 percent of the corn planted in Brazil.
Monsanto's corn seed products, sold locally through the Dekalb and Agroceres seed brands, are currently used on approximately 30 percent of corn acres in Brazil.
"Agroeste will serve as an important complement to our existing national brand approach in Brazil," said Brett Begemann, Monsanto's executive vice president of global commercial.
The acquisition of Agroeste, which focuses on hybrid corn seed production , is expected to enhance Monsanto's existing corn germplasm portfolio, enabling it to develop new higher-yielding seed varieties.
"The acquisition will allow our companies to provide new and innovative higher yielding seed offerings through multiple brands and will bolster our genetics platform for the introduction of our trait technologies longer term," said Begemann.
Monsanto also said that the combination of each company's germplasm portfolios is expected to support the introduction of biotech trait offerings in Brazil longer term.
Brazil is currently the world's third largest corn production area.
In the 2006-2007 growing season, Brazilian farmers planted approximately 30 million acres of corn.
Monsanto said it estimates that the Brazilian hybrid corn seed market is 23 million acres.
Last month, the Brazilian National Biosafety Technical Committee(CTNBio) approved Monsanto's MON 810 insect protection event, known in the United States as YieldGard Corn Borer, for future commercial use in corn in Brazil.
According to Monsanto, the CTNBio approval may be followed by a review from the National Biosafety Council (CNBS) to examine social and economic factors.
The seeds will be available for planting following a favorable review by CNBS, and approvals of the individual MON 810 events in specific hybrid varieties.