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"Millions served" - the GM sweet potato

The virus-resistant sweet potato has been the ultimate GM showcase project for Africa, generating a vast amount of global media coverage. The Monsanto-trained scientist fronting the project has been proclaimed an African heroine and the saviour of millions, based on her claims about the GM sweet potato doubling output in Kenya. Forbes magazine even declared her one of a tiny handful of people around the globe who would "reinvent the future". It eventually emerged, however, that the claims being made for the GM sweet potato were bogus, with field trial results showing the GM crop to be a dud.

"Millions served," ran the headline in the US magazine Forbes over an article that declared, "While the West debates the ethics of genetically modified food, Florence Wambugu is using it to feed her country."[1]

Florence Wambugu is the Monsanto-trained scientist who headed up a project to create a genetically engineered virus-resistant sweet potato for farmers in Kenya. It was a showcase project intended to position GM as the saviour of Africa, and Florence Wambugu travelled the world promoting it.

"In Africa GM food could almost literally weed out poverty," she told New Scientist.[2] In the journal Nature she wrote, "There is urgent need for the development and use of agricultural biotechnology in Africa to help to counter famine, environmental degradation and poverty. Africa must enthusiastically join the biotechnology revolution."[3] Such a revolution, she told a Canadian newspaper, could pull "the African continent out of decades of economic and social despair".[4] She was also invited to contribute to the New York Times, and to appear on CNN as well as several American TV shows.

Her media popularity was understandable. The results of sub-Saharan Africa's first GM crop were "astonishing", according to the article in Forbes magazine.[5] Yields were "double that of the regular plant", with "potatoes bigger and richer in colour", indicating they'd retained more nutritional value. For hungry Africa, we were told, "Wambugu's modified sweet potato offers tangible hope".

In a report published in January 2004, the Nuffield Council on Bio-ethics said the project "could prevent dramatic and frequent reductions in yield of one of the major food crops of many poor people in Africa."[6]

Contrast such claims with the actual results of the 3-year trials - quietly published at the end of January 2004. Under the headline "GM technology fails local potatoes", Kenya's Daily Nation reported, "Trials to develop a virus resistant sweet potato through biotechnology have failed. US biotechnology, imported three years ago, has failed to improve Kenya's sweet potato."[7]

In fact, far from dramatically out-yielding the non-GM sweet potatoes, the exact opposite was the case: "The report indicates that during the trials non-transgenic crops used as a control yielded much more tuber compared to the transgenic". The GM crop was also found to be susceptible to viral attack - the very thing it had been created to resist.

New Scientist also reported the GM crop's failure ("Monsanto's showcase project in Africa fails"),[8] as did an article in the British daily paper, The Guardian. The success of the GM sweet potato had previously been reported in literally hundreds of articles, even generating headlines like Transgenic sweet potato could end Kenyan famine.[9]

Even before the results were announced, Aaron deGrassi of the Institute of Development Studies had revealed how people had been seriously misled about the GM sweet potato project. According to a piece in the Toronto Globe & Mail, "Dr. Wambugu's modified sweet potato... can increase yields from four tonnes per hectare to 10 tonnes."[10] A piece in Canada's National Post repeats exactly the same figures: "Dr. Wambugu... said the modified sweet potato seeds should be able to produce 10 tonnes of vegetables per hectare compared with a natural Kenyan crop that yields four tonnes per hectare."[11] But deGrassi examined all the available data and discovered, "Accounts of the transgenic sweet potato have used low figures on average yields in Kenya to paint a picture of stagnation... FAO statistics indicate 9.7 tons, and official statistics report 10.4."[12]

In other words, Wambugu's figures on average non-GM yields understate the reality by as much as 60%. So if, as Wambugu claimed, her GM sweet potato were producing 10 tonnes per hectare, then rather than roughly doubling normal yields, the GM sweet potato would be performing no better than the conventional crop.

Aaron deGrassi also drew attention to the contrast between the unproven GM sweet potato variety and a successful conventional breeding programme in Uganda which had already produced a new high-yielding variety which was virus-resistant and "raised yields by roughly 100%". The Ugandan project achieved success at a small cost and in just a few years. The GM sweet potato, in contrast, in over 12 years in the making, consumed funding from Monsanto, the World Bank and USAID to the tune of 6 million dollars.

Nothing could better illustrate deGrassi's point that "the excitement over certain genetic engineering procedures can divert financial, human, and intellectual resources from focusing on productive research that meets the needs of poor farmers."


1. Lynn J. Cook, "Millions served", Forbes magazine, 23 December 2002, accessed 10 June 2009

2. Fred Pearce and Florence Wambugu, "Feeding Africa", New Scientist, 27 May 2000, accessed in the Gentech archive, 10 June 2009

3. Florence Wambugu, "Commentary: Why Africa needs agricultural biotech", Nature 400, 15-16, 1 July 1999, abstract here, full article reprinted here, both accessed 10 June 2009

4. Chris Lackner, "GM crops touted to fight poverty", National Post, 28 June 2003, accessed 10 June 2009

5. Lynn J. Cook, "Millions served", Forbes magazine, 23 December 2002, accessed 10 June 2009

6. "The use of GM crops in developing countries", Nuffield Council on Bioethics, January 2004, p. 43, accessed 10 June 2009

7. Gatonye Gathura, "GM technology fails local potatoes", The Daily Nation (Kenya), 29 January 2004, accessed 10 June 2009

8. "Monsanto's showcase project in Africa fails", New Scientist, Vol. 181, No. 2433, 7 February 2004, accessed 10 June 2009

9. Naftali Mungai, "Transgenic sweet potato could end Kenyan famine", ENS, 15 September 2000, accessed 10 June 2009

10. Margaret Wente, "Breaking the food chains", Globe & Mail, 5 July 2003, accessed 10 June 2009

11. Chris Lackner, "GM crops touted to fight poverty", National Post, 28 June 2003, accessed 10 June 2009

12. Aaron deGrassi, "Genetically modified crops and sustainable poverty alleviation in sub-Saharan Africa: An assessment of current evidence", Third World Network-Africa, June 2003, accessed 10 June 2009