The risks of genetically modified crops still outweigh the benefits

The technology of genetically-modified crops as it has been developed so far fails to provide sufficient benefits to outweigh the risks; unless other evidence is forthcoming that is very different, the Government must not license these crops.

The results of the farm trials of genetically-modified crops are surprisingly definite. On the evidence of the findings so far, there is simply no case for the Government to endorse the widespread commercial growing of such crops.

In two of the three cases, the effect of using the different weedkillers suitable to the genetically-modified crop adversely affected wildlife. That may not seem surprising: one of the purposes of this kind of biotechnology is to allow more effective herbicides and pesticides to be used to control weeds and pests without harming the crop itself. Fewer weeds means fewer - and fewer varieties of - insects, and that in turns means fewer corn buntings, skylarks and yellowhammers.

In fact, the proponents of genetic modification claimed this would not be so. They said that their new crops would allow more effective, targeted herbicides to be used instead of the present cocktail of different chemicals, and would therefore be kinder to wildlife. That claim has now been refuted.

In the case of sugar beet and spring-sown oilseed rape, the cultivation of genetically-modified varieties reduced the biodiversity of the immediate environment. In the third case, that of maize, it improved it, but this might only have been because the conventional maize was treated with a harsh weedkiller that is being phased out before being banned.

Of course, these were limited trials of a narrow issue, that of the effect on biodiversity. There are three other issues. One is whether it is dangerous to eat food from genetically-modified crops. On that, no one has suggested a plausible reason why it should be. The second is whether such crops could cross-pollinate with other plants, including weeds, with "unpredictable" results that have in fact already been predicted, including the creation of herbicide-resistant super-weeds. On that, the jury is still out.

The last issue is whether biotechnology can significantly raise yields. So far, it has only been able to do that by allowing more effective control of weeds and pests - which has the effect on biodiversity that was assessed in the trials reported yesterday.

To simplify, therefore, the choice comes down to enhanced yields versus reduced biodiversity. Broadly, that is the same choice that has been offered by intensive farming since the Industrial Revolution. And there has been a growing recognition in recent decades that farming policy should be tending in the opposite direction to that offered by today's genetically-modified crops. The movement should be away from intensive farming and towards the preservation of biodiversity. You do not have to be a fully-subscribed 100 per cent organic enthusiast to appreciate that the environmental costs of modern farming methods are too high.

The priority should not be the further intensification of single-crop and single-livestock farms. Instead, it should be the ending of subsidies and tariffs, the protection and restoration of ancient habitats and the promotion of animal welfare.

That does not mean, as Greenpeace urged yesterday, that the Government should "shut the door" on genetic technology. Science is part of the solution to the problems of global sustainability, not an obstacle.

It may yet be that genetic engineering could produce huge benefits to humankind, helping to feed the multitudes and cure them of all manner of diseases. Those were the promises that lured a technocratic Prime Minister into uncritical support for Britain's biotechnology industry. And it must be suspected that there is a political imperative driving this Government towards a favourable verdict on the farm trials of crops.

But yesterday's findings strongly suggest that the technology as it has been developed so far fails to provide sufficient benefits to outweigh the risks. Unless other evidence is forthcoming that is very different, the Government must not license these crops.