Monsanto, the controversial GM food giant, is undergoing a bit of a name change.

Plans are to discreetly drop the M-word from letterheads as part of the US firm's merger with drugs group Pharmacia and Upjohn.

The combined company will go by the name of Pharmacia, although "Monsanto" will be retained for its autonomous agricultural subsidiary.

Despite this important concession, the move has prompted speculation that bosses are trying to downplay the Monsanto name.

If so, it certainly wouldn't be the first time marketing managers had dreamed such a wheeze.

One of the best examples is that of High Street jeweller Ratners.

In 1991 it took just two words - "total crap" - from then chairman Gerald Ratner, who was describing one of the company's products, to torpedo consumer confidence and bring it to the brink of bankruptcy.

"Consumers would have been totally embarrassed and humiliated to have bought its product. It just became impossible," says Tom Blackett, group deputy chairman of London-based branding consultancy Interbrand.

The firm parted company with Mr Ratner, threw the focus on to its "trusted brands" H Samuel and Ernest Jones, and renamed itself Signet.

At the start of this year it produced a strong trading statement and confirmed rocketing pre-Christmas sales.

Mr Blackett reckons it takes about 10 to 15 years for such a brand gaffe to be forgiven and forgotten.

But sometimes memories take much longer to fade.

After a serious fire at the Windscale atomic works in 1957, in which massive amounts of radioactive energy were released, the Cumbria site was rebranded Sellafield.

Although the name of the site has never officially been changed, the operators were clearly trying to put distance between the disaster and the nuclear plant as a whole.

However, the new epithet has failed to generate goodwill on a large scale.

Julian Gorham, creative head of the Brand Naming Company, blames the fact the name change was not matched by significant organisational changes.

"Windscale, Sellafield, it's the same thing, isn't it? Nothing has changed."

And consider the exotic sounding Sea River Mediterranean, which is more likely to conjure up visions of long balmy holiday evenings, than an horrendous oil slick.

It is actually the new name of the Exxon Valdez, the supertanker which leaked hundreds of thousands of gallons of oil off the coast of Alaska in 1989, devastating 25,000sq km of eco-system in its wake.

Still barred from the Prince William Sound, where the disaster happened, it has since been seen merrily sailing around the Firth of Forth.

Cynical investors

Exxon itself, however, did not change its name post disaster with good reason.

"The interesting thing about the Exxon Valdez affair was that it had virtually no impact on Exxon's share price," says Mr Blackett.

"Which possibly shows just how cynical investors are."

The public, though, are more judgmental, and many people would be glad to see the back of the name "Monsanto".

Brand experts however, praised bosses for keeping the controversial name for Pharmacia's agricultural output.

"Monsanto is doing exactly the right thing," says Mr Blackett. "It remains totally committed to GM as a business, so a name change would be pointless."

Mr Gorham agrees: "Changing a brand name is usually a bad idea, even after a real crisis.

"Firms have so much positive equity tied up in brands. People still know what Monsanto is, for instance. Changing the name would mean delivering a whole new identity - and that costs a lot of money."

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