British ministers, having given the go-ahead for the experimental planting of GM crops, ought to be able to look to Argentina for inspiration. This is the country that has embraced GM technology most wholeheartedly. Today, more than half of its arable land is covered with GM soya, which was developed by Monsanto and is sold as Roundup Ready (RR) because it has been engineered to be resistant to Roundup, the company's trademarked glyphosate herbicide.
Yet something has gone wrong. Argen-tina's main agricultural research institute has warned that, unless the move into RR soya monoculture is reversed, "a decline in agricultural production will be inevi-table". And in January Monsanto abruptly halted the sale of its GM soya seeds.
At first, GM technology seemed like a gift for farmers. The pampas, an area of rich land that fans out for roughly 600 kilometres around Buenos Aires, were suffering from serious soil erosion, caused partly by repeated ploughing. RR soya seemed the solution: it allowed farmers to control weeds by spraying glyphosate during the growing season and thus farm without ploughing. The proliferation of weeds had earlier made such no-till farming unsuccessful.
Driven by the huge demand on the world market for soya meal as cattle fodder, farmers enthusiastically adopted the technology. At the time, with encouragement from the IMF, Argentina had adopted free-market economics. Soya looked like an ideal export product where the country had "comparative advantage". Monsanto sold Roundup at a special cheap price and exempted farmers from royalty payments. The area under soya cultivation increased by 60 per cent in the second half of the 1990s; output more than doubled.
After a currency collapse in December 2001, only export crops remained profitable. Quick-witted businessmen set up investment trusts that scoured the country in search of land to plant with soya. Soya spread beyond the pampas into more environmentally fragile areas in the north, joining fields in Brazil and Paraguay to form a vast "soya republic".
About 150,000 small farmers, who had cultivated rice, maize, lentils, potatoes, fruit and other food crops, were driven off the land, hit both by low prices for their products and by herbicide contamination from soya farmers' spraying. Land ownership in Argentina is more concentrated today than at any time in history. Moreover, new weeds, probably naturally resistant to glyphosate and opportunistically occupying the new ecological niche, are proliferating. RR soya, sprouting inconveniently from seeds dropped during harvesting, is also becoming a nuisance. Farmers tried upping the frequency and strength of Roundup applications. Sales of glypho-sate rose from 5.4 million litres in 1994 to 59.2 million litres in 1998, and probably to well over 100 million litres now.
Even so, the farmers have been losing the battle. So biotechnology companies have come up with a new technical fix. Syngenta's advert proclaims that "soya is a weed" and advises farmers to spray their fields, prior to planting, with two notoriously damaging herbicides - Gramoxone (paraquat) and Gesaprim (atrazine).
These are exacerbating the damage to neighbouring farms. I recently visited a peasant hamlet near the border with Paraguay. The families' small subsistence plots have become islands in a sea of soya. One day last year, soya farmers sprayed one of the new mixtures on a nearby farm. "The wind was in the north, so the toxic cloud got blown on to our plots and into our houses," recalled Sandoval Filemon. "Our eyes immediately started smarting." Over the next few days chickens, pigs and goats died. Sows gave birth to deformed or dead piglets. And almost all the crops were badly damaged, said Eugenia, Sandoval's wife. Even today, the banana trees produce stunted fruit.
Because of their heavy use of herbicides, soya farmers also kill off bacteria in the soil, leading to more snails, slugs and fungi. As the normal process of decomposition is interrupted, some farmers have to brush dead vegetation off the land prior to planting. Charles Benbrook, a US agricultural economics consultant who has studied GM farming in Argentina, told me that without big changes in farming practice, Argentinian agriculture will not be sustainable for longer than another two years.
Even Monsanto appears to have qualms. In response to my queries about the sustainability of RR soya, it said it "strongly supports crop rotation", something that it has not encouraged in practice. It is also trying belatedly to regain control over the soya sector by charging royalties. But the farmers are resisting, either by saving seeds at harvest time to plant the following year or by buying RR seeds on the black market. Monsanto suspended seed sales in January and could introduce an extra "terminator" gene into other GM crops to sterilise seeds and stop hoarding.
The case of Argentina shows that genetic modification of crops, by its very nature, permits farmers to indulge in irresponsible practices such as deluging the soil with glyphosate, something that would be impossible in conventional farming. In less than a decade the rush into soya farming has driven thousands of families off the land, created serious ecological and agronomic imbalances, destroyed food security and led to dependence on a technology controlled by a handful of multinational companies. GM technology, though not wholly responsible, has played a part while contributing only a temporary increase in yields and a short-lived solution to the problem of soil erosion.
Sue Branford is co-author of Cutting the Wire: the story of the landless movement in Brazil (Latin America Bureau, 2002)