Gm Crops

Genetically modified crops are now grown in more than 16 countries. In 2002, farmers around the world planted 60 million hectares of land with dozens of varieties of GM crops. Yet in the UK, the decision to approve or reject the technology could hinge on the results, out on Thursday, of four-year trials involving 280 fields of three GM crops.

Although these farm-scale evaluations are being portrayed as a test of the environmental credentials of GM crops, it is really the weedkillers to which they are resistant that are on trial.

The studies looked only at the effect that these herbicides had on "wildlife" in fields, in the form of weeds and insects. But if the aim of the exercise really is to save farmland wildlife, banning any of the GM crops tested is unlikely to make much difference.

That is because herbicide use in the UK is soaring even before any GM crops are introduced. And in the long term, farmers denied GM crops may instead turn to non-GM crops bred to be resistant to herbicides. That might seem like a good thing to those who oppose GM technology, but like GM crops, the conventionally bred strains allow farmers to splash on the herbicide.

Their impact on farmland wildlife in Europe could be worse than that of the weedkiller-resistant GM crops, because many allow the use of more noxious herbicides than GM strains. And as with GM crops, the herbicide-resistance could spread to other crops and wild relatives.