Global chemical manufacturer BASF plans to acquire Ames-based Becker Underwood Inc. for $1.02 billion, the companies announced Thursday.

Becker Underwood, which operates 10 production sites worldwide, is one of the leading global providers of biological seed treatment and related technologies.

Founded in 1982, Becker Underwood has grown into a multinational company with 14 locations on five continents. Norwest Equity Partners has owned a majority stake in the company since 2004.   

The acquisition will strengthen BASF’s crop protection division in rapidly growing seed treatment market, BASF officials said in a release.The deal is expected to close by the end of the year. 

Upon receiving the necessary legal approvals, the majority of Becker Underwood’s business will be integrated into BASF’s Crop Protection division.

“Becker Underwood has a strong position in North America. We will continue to expand this core business as we expand globally,” said Markus Heldt, President of BASF’s Crop Protection division. “We are thrilled at the prospect of working with the highly-qualified employees at Becker Underwood as we continue to develop our combined businesses.”

Becker Underwood is expected to achieve sales of $240 million for fiscal year 2012, which ends Sept. 30.

As part of the acquisition, BASF’s Crop Protection division will create a strategic global business unit called Functional Crop Care. The unit will merge BASF’s existing research, development and marketing activities in the areas of seed treatment, biological crop protection, plant health, as well as water and resource management with those of Becker Underwood. Becker Underwood’s animal nutrition business will be integrated into BASF’s Nutrition & Health division.