LONDON — The Canadian auto parts maker Magna International said on Thursday that it had agreed to acquire one of the world’s largest suppliers of automotive transmissions, the Getrag Group, for 1.75 billion euros, or about $1.9 billion.

The deal will bolster Magna’s powertrain and transmission business and increase its growth potential in the Chinese market.

Getrag is a joint venture partner with Ford and its customers include BMW, Daimler, Renault and Volvo. It also has joint venture relationships with Chinese automakers Jiangling and Dongfeng.

“As part of our ongoing product portfolio review, we have identified the expansion of our powertrain business as a strategic priority,” Donald J. Walker, the Magna chief executive, said in a news release.