The Monsanto company name, which has become synonymous with the genetically modified food business, is to be ditched, the company revealed last night.

The beleaguered American biotech company is merging with the US-Swiss drugs group Pharmacia & Upjohn and the $50bn corporation will in future be known as Pharmacia.

"We have chosen a name with power and global relevance," said Robert Shapiro, chairman of Monsanto, who will lead the new company. "This name and logo will create a strong new identity for our 60,000 employees and will build value with our existing customers worldwide."

Mr Shapiro, who championed GM food, was once regarded as a visionary who would mix nutrition, biotechnology, crop protection and medicine in one commercial venture. But the Monsanto name became tainted last year as the consumer backlash against GM food spread from Europe to the US.

In addition to food safety and environmental fears there were concerns that farmers in developing countries would never be able to afford the new Monsanto seeds.

Last month a shareholder campaign in the US unveiled a plan to target 24 companies, including Monsanto, demanding a moratorium on the use of GM food until independent testing had been completed. The campaign is being coordinated by 275 religious and other groups which claim to control $100bn of shares in US companies.

Monsanto, which had been a high-flying pharmaceutical stock and darling of Wall Street, fell swiftly from grace when its crop technology business, which little over a year ago was regarded as a world beater, turned into an albatross. Shareholders watched as their investments lost a third of their value.

The newly merged Pharmacia Corporation will use the names Searle, Pharmacia and Upjohn for its three sales divisions. Only an autonomous agricultural subsidiary will continue to use the Monsanto name.