The Prince of Wales is a man of social conscience who acts with complete propriety in intervening in public debate. And his concern for the environment is scrupulously politically disinterested. Unfortunately, his apocalyptic predictions of the effect of genetically modified crops do not enhance public debate, but degrade it.

He maintains that GM crops augur environmental catastrophe. He fears that food will run out owing to damage to the world's soil through scientific research. His views are worse than wrong. They would not deserve a place beyond the fringe of political debate if they came from a pressure group. Coming from the heir to the throne, they encourage one of the most corrosive aspects of popular culture: a suspicion of science as an amoral and anti-humanist force, allied to big business.

Not every criticism of this particular innovation is groundless. Multinational companies play an important role in scientific research and development, as they do in economic development. But if the technology of genetic modification of plants is left solely to large corporations, then the great promise of new crops - feeding the hungry and improving the living standards of the desperately poor - might not be fully realised.

There is a market for GM crops in the advanced industrial economies, in particular in providing cheaper food when prices are high and rising. And there is also a desperate need for GM crops in the poor world. A greater public sector effort in plant breeding and research might mitigate the risk that the technology will be skewed to more affluent consumers. The irony is that where anti-GM campaigners win popular sympathy, then the greater is the likelihood that public finance for research will stagnate or decline.

GM developments carry risks; but that is a truism rather than an objection. Complete certainty about the consequences of technological advance is never available. Some genetic modification might have ill effects in some circumstances. But there is literally no evidence that GM crops carry special risks - let alone the “guarantee”, in the Prince's words, of the world's biggest environmental disaster ever.

It is indeed a matter of wonder among US commentators that in Europe this is a contentious issue. Americans have consumed food derived from GM crops for the past decade, with no obvious ill effect on public health. The US is a society with a reputation for litigiousness, by and against government agencies. If there were a latent public health scandal, it is hardly credible that it would as yet be undiscovered.

GM crops are not a panacea, and the scientists who work on them are not soulless technocrats. Genetic modification is a technology that can provide benefits to the poorest on Earth. It offers the potential for crops that can resist viruses and pests, and tolerate hot, saline or otherwise inhospitable conditions. It is no more “against nature” than are horticulture, animal domestication or medical vaccines.

There lies the most ominous aspect of the royal critique. The Prince's alarmism about GM crops goes beyond aesthetic appreciation of the rural. It is more akin to his enthusiasm for “alternative medicine” (an enterprise best regarded as alternative to medicine). But whereas the costs of homoeopathy are limited - the purported medicines at least do no active harm - the costs of agitation against GM crops may be measured in penury and starvation.

The Prince is not, on this issue, defending the environment against human destructiveness. He is speaking for obscurantism, reaction and superstition. There is quite enough nonsense in public debate without its having a Royal Warrant.