Monsanto, the world's largest genetically modified seed company, has been awarded patents on the wheat used for making chapati - the flat bread staple of northern India.

The patents give the US multinational exclusive ownership over Nap Hal, a strain of wheat whose gene sequence makes it particularly suited to producing crisp breads.

Another patent, filed in Europe, gives Monsanto rights over the use of Nap Hal wheat to make chapatis, which consist of flour, water and salt.

Environmentalists say Nap Hal's qualities are the result of generations of farmers in India who spent years crossbreeding crops and collective, not corporate, efforts should be recognised.

Monsanto, activists claim, is simply out to make "monopoly profits" from food on which millions depend. Monsanto inherited a patent application when it bought the cereals division of the Anglo-Dutch food giant Unilever in 1998, and the patent has been granted to the new owner.

Unilever acquired Nap Hal seeds from a publicly funded British plant gene bank. Its scientists identified the wheat's combination of genes and patented them as an "invention".

Greenpeace is attempting to block Monsanto's patent, accusing the company of "bio-piracy".

"It is theft of the results of the work in cultivation made by Indian farmers," said Dr Christoph Then, Greenpeace's patent expert after a meeting with the European Commission in Delhi.

"We want the European Patent Office to reverse its decision. Under European law patents cannot be issued on plants that are normally cultivated, but there are loopholes in the legislation."

A spokesperson for Monsanto in India denied that the company had any plan to exploit the patent, saying that it was in fact pulling out of cereals in some markets.  "This patent was Unilever's. We got it when we bought the company. Really this is all academic as we are exiting from the cereal business in the UK and Europe," said Ranjana Smetacek, Monsanto's public affairs director in India.

Campaigners in India say that there are concerns that people might end up paying royalties to Monsanto for making or selling chapatis.

"The commercial interest is that Monsanto can charge people for using the wheat or take a cut from its sale," said Devinder Sharma, who runs the Forum for Biotechnology and Food Security in Delhi.

The potential market in developing countries is huge. Rice production in India alone exceeds that of the American maize market.

The number of patents relating to rice issued every year in the US has risen from less than 100 in the mid-1990s to more than 600 in 2000.

Mr Sharma says there is little hope of the Indian government intervening to prevent the chapati being patented by Monsanto.

It simply cannot afford the legal fees, having spent hundreds of thousands of dollars fighting a US decision to grant a Texan company a patent on basmati rice in 1997.

That case became a cause celebre for the anti-globalisation protests of the 1990s, and was only settled when the patent was watered down.

"The ministry of commerce sent a circular out last year which said that there is no money to fund these cases any more," said Mr Sharma.