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[CAPE TOWN] The promise that genetically modified (GM) cotton would boost yields and profits for small-scale farmers in South Africa is already coming true, according to new research.

A study of cotton grown by more than 2,000 farmers showed that those that planted Bt cotton — which has been genetically engineered to resist the bollworm pest — benefited by US$86 to US$93 per hectare more than those that planted conventional strains.

This is the first time that Bt cotton in Africa has been assessed on the basis of farmers' own practice, rather than on the results of controlled field trials. The results could be significant for Africa's agricultural economy: cotton is grown on 2.5 million hectares of the continent, most of it on small plots of less than 10 hectares.

A team of scientists from Reading University, United Kingdom, analysed three seasons of records from farmers leasing state land in the Makhathini Flats on northeast coast of South Africa. They also carried out interviews and in-depth case studies with farmers.

Writing in this month's Nature Biotechnology, the researchers say that Bt cotton gave better yields in each of the three seasons studied, and that the results were particularly striking "in the poor, wet growing season of 1999-2000, which favoured the bollworm".

In fact, farmers who did not use the GM cotton seed "had a negative gross margin, which resulted in them having difficulty paying back credit that they had borrowed".

The consistently higher yields with GM cotton over several years appears to contradict claims by the Cape Town environmental organisation Biowatch that floods late in the 2000/2001 season distorted the results because the GM cotton was an early-maturing variety.

Charles Louw, an independent consultant commissioned by Biowatch to conduct socioeconomic research among about 40 farming families in the Makhathini Flats, expressed surprise at the results. "Climate is an overwhelming factor, bigger than either GM or non-GM factors," he says.

Louw adds that, owing to bad weather over the past three years, only two small-scale farmers in his research reported successful seasons. Both farmers attributed their progress to external factors that had nothing to do with genetic modification. He also says that his research, which will be published later this year, suggests that farmers and government agricultural advisors do not understand the concept of genetic engineering.

Bt cotton seeds are more expensive than conventional ones. But according to the research in Nature Biotechnology, this is more than compensated for by lower pesticide costs, both in terms of buying the product and the cost of hiring labour to apply it.

Carl Reynolds, chief technical officer of Vunisa, a company that sells farmers seeds on credit and then buys their harvests, confirms that farmers that plant Bt cotton have to pay a considerable 'technology fee' up front, equivalent to the savings in one hectare. "It's an additional cost of about 700 rands (US$105) per bag of seed, although you can plant two or three hectares with that bag," he says.

Vunisa sells both unmodified and GM seeds. But Reynolds estimates that at least 80 per cent of their seed sales is now of the bollworm-resistant variety.

The reduction in pesticide spraying costs that Bt cotton provides is a significant factor, according to GM advocate Jocelyn Webster of the AfricaBio biotechnology association and the University of Pretoria's Forestry and Agricultural Biotechnology Institute. She says that in each growing season, labourers have to walk as much as 400 kilometres with heavy knapsacks on their backs to spray a four-hectare plot up to eight times.

Andrew Bennett of Monsanto South Africa, which distributes the Bt cotton seeds, says that the GM strains actually give the poorer farmers, often women, a bit of an advantage. "There was no evidence that wealthier farmers gained more than the less affluent: indeed, income inequality was slightly reduced," he says.

Link to full article in Nature Biotechnology

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