Living and working near Mexico City and about to celebrate his ninetieth birthday is someone who in the past century, by personal intervention, saved more lives than anyone else in human history — about a thousand million people.

The green lobby hates his achievements. And you? If you belong to the 99 per cent of our countrymen who have never heard of Dr Norman Borlaug, you are as ignorant as I was about him before I went to Mexico to meet this man and make a television documentary about him for BBC Four.

Our discussions have helped me to make up my mind about biotechnology and GM food. A month ago I would have been alarmed by the leak that shows the British Government is about to give the go-ahead for the use of genetically modified crops. I used to view the intervention of science in agriculture with doubt. Now I see it as a reason for hope.

Dr Borlaug has been a key transitional figure in his field. He has spent his life on the cusp between traditional farming and biotechnology. He has concluded that only by the responsible application of science to agriculture can we save the world from famine. Since he won the Nobel Peace Prize 33 years ago, Dr Borlaug has stood at the centre of one of the greatest and, in its way, the most dramatic success stories in the history of farming.

Borlaug’s work saved the Indian sub-continent from mass starvation. In his 90 years on this planet its human population has grown from about one billion to more than six billion. Without the hybrid wheats it was Borlaug’s life’s mission to develop and promote among the world’s poorest farmers, few believe that this population could have been sustained.

It is as simple as that. Yet in the fog of mysticism, pseudo-science and sentimentality that fashion has blown in upon the rich, leisured and fat — that is, us — we forget our own history. Interfering in nature is what has put us where we are today. It is the reason you are reading this, the reason you can read, the reason you have time to read, the reason nine tenths of us are alive.

Let me begin in the single-room school in Iowa where one teacher taught children aged from age 5 to 17, and where Norman Borlaug began an education which took him into university, forestry, then agronomy. He remembers the abuse of monoculture in farming, the dustbowls of the Thirties, the disappearance from the environment of deer and wild turkeys, and the corn in his boyhood, standing As high/ As an elephant’s eye. The corn is lower today, he says: more productive hybrids have been developed. Crop yields are up; marginal land has been taken out of production; wild areas have been reclaimed for nature; and the deer and wild turkeys are back in force.

When he was a young scientist in the 1940s he was sent by the Rockefeller Foundation to run a project in Mexico. The country’s wheat harvests were being devastated by stem rust. As they shuttled between the climates of the highlands and the plains so that they could plant two generations each year and test results in both environments, Borlaug and his colleagues developed a drought-hardy, rust-resistant strain of wheat, then crossed it with a dwarf Japanese strain to produce a hybrid short enough to survive the wind and channel growth into grain.

Borlaug did not invent hybridisation. Mankind had started to do that a few thousand years ago when hybrid grasses thrown up by nature were gathered from the wild and developed under unnatural (ie, weeded) conditions in a wheatfield (ie, monoculture) and fertilised artificially (ie, with gathered dung). The dung was collected from genetically modified (ie, domesticated) beasts.

Borlaug built on what was known. He concluded that better hybrids could be produced in a more systematic way, and faster, and promoted among peasant farmers more successfully, than the world had yet realised.

He proved to be not only an effective scientist but also a charismatic salesman. Farming folk are the same the world over, he says: they want to see for themselves results produced on their own soil. Don’t tell them, show them; and do it on farms such as theirs.

From total dependence on wheat imports, Mexico had within a few years shifted to being to a net exporter of wheat. Though skilful, Borlaug had also been lucky. Maize is Mexico’s principal crop; he had been able to use the wheat sector as a sort of pilot for his approach.

The Indian sub-continent was different. Here there was huge dependence on wheat, and the population was rocketing. When Borlaug began work there in the 1960s massive starvation looked unavoidable. To widespread scepticism, he imported his new seed and began his missionary science.

He knew that fertilising exhausted soil was a key to increasing yields. Dung and compost were insufficient. “Use all the organic materials you can,” says Borlaug, “but don’t come to Third World nations and tell them they can solve their problems with organic fertiliser alone.” He points to the environment wrecking sixfold increase in cattle numbers which would be needed.

His Indian experiment succeeded beyond the wildest hopes. Wheat production quadrupled in a decade; by today that increase is tenfold. The region’s population has more than doubled, yet its people are better fed than they have been in more than half a century. For Dr Borlaug the Nobel Peace Prize followed in 1970.

Later, his hybrid wheat reached China. In China population growth is now coming under control. This is one of three observations worth holding on to if you are to follow me to a conclusion which (against the tenor of our times) is optimistic. First, world population is not — contrary to widespread belief — spiralling out of control. Though still our planet’s biggest worry, the rate of growth shows signs of reducing. Most projections see a gradual flattening of the increase until a point after the middle of this century when the world population may stabilise at about double its present level.

Second, starvation is not an effective form of birth control. In fact, the more secure and well fed people become, the fewer children they have. The harsh but seemingly plausible argument that producing more food is pointless because extra food will be met by more hungry mouths to feed is wrong.

Third, better crop yields do not add to the pressure on rainforests or on wild or marginal land: they reduce it. To hack into hillsides, swamps and woodland is often the resort of agriculturalists who are desperate. Without the extra millions of tons of cereals which work such as that of Borlaug now produces from existing ancient farmlands, hungry populations in Asia would be higher up the mountainsides and deeper into former forests in search of land to till. Intensive farming allows us to limit the land under the plough.

In short, this is a battle mankind can win. Norman Borlaug sees his life’s work as part of a holding operation until a time he will not live to see: when population stabilises. He persuaded me that the challenge, though immense, is finite: to feed another six billion people in the half century ahead.

He believes this is possible. His dream, he told me, is that biotechnology will find a way to impart to other cereals the famous hardiness of the rice family. This may achiev able by genetic modification.

Borlaug’s work has not been, properly speaking, in GM. He has used “natural” methods (if you are prepared to call a pekingese or boxer dog “natural”) of breeding. His genius strikes me as having lain in systematisation, acceleration, evangelism and hunch.

This has not prevented many in the green movement from vilifying what in its day was called Dr Borlaug’s “Green Revolution”. Greens hate the Green Revolution. Their case (if I can understand it at all) is that “traditional” crops and methods are best; but the term “traditional” defies useful definition, ignoring the damage that traditional low- intensity farming (for instance in Africa) can do to the environment.

Though he was initially sceptical about GM as applied science, Borlaug is now persuaded of its promise. He is wary of the patent-hogging multinationals but he nevertheless believes that by driving GM scientists out of universities and public institutions we are in danger of helping profit-making interests to corner science.

I put it to him that if he really thinks knowledge must triumph, then he should have no fear of the pseudo science of the green lobby. He replied that by distortion and intimidation Lysenko wrecked research right across Russia and set back Soviet science by 30 years.

I had forgotten about the lunatic plant science of the Stalinist Trofim Lysenko. But I recognise in the green lobby Borlaug’s warning about distortion and intimidation. How shaming that to sound a warning we must turn for moral authority to a 90-year-old hero of 20th-century science.

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