The small plant in my hand is a miracle. The potential saviour of millions of lives. This is one extraordinary sprout of lifesaving shrubbery, and the strange thing is that if I were to walk out of this sealed laboratory in Norfolk with this totally harmless sprig of wheat in my hand and take it into the open air, I could be arrested.  Welcome to the crazy world of genetic hysteria - an irrational terror that is threatening the ability of our species to feed itself as it peers into a demographic abyss.  Just after midnight tonight, the world's human population passes a milestone. Somewhere, perhaps in an african or Punjabi slum, a child will be born and arbitrarily designated by the United Nations as the 7 billionth human alive. The growth in population in the past century has been astounding, perhaps the defining statistic of the modern world. Humanity has added a whole billion to its number since 1999, when a Bosnian baby, adnan Nevic, was identified as the 6 billionth person.  The growth in human population is, arguably, the biggest problem facing our species and our planet. It is hard to imagine any current issue, from food security to habitat loss, climate change or energy shortages, that would not be alleviated by fewer people. and of course humanity will not stop growing at 7 billion: depending on which estimate you believe, the total will peak some time in mid-to-late century at about 8 billion (the most optimistic scenario) or, alternatively, continue to swell well beyond 10 billion and still be growing in the 2100s.  The big question is - even if the optimists are right - how are we going to feed, water and power the equivalent of between one and two extra Chinas in just a generation or two? Nearly all of these extra people will be in africa and southwest asia - places where crop yields are a pitiful sixth of what they are here, and that are faced with periodic droughts and riddled with disease and pests. Even here in Britain the population is expected to grow by about 5m a decade, hitting 70m in 2027, an increase largely fuelled by immigration.  Britain is rich, but africa, in particular, cannot feed itself right now. One billion people are permanently hungry and dependent on food aid, and food prices are at an all-time high. If we are not to see famine and food insecurity on an unprecedented scale, something drastic is going to have to be done.  Of course, the sceptics will say, we have been here before. In 1798 the economist and cleric Thomas Malthus predicted famine as population growth outstripped food supply. Then, in the 1960s, we had a new demographic panic when the american ecologist Paul Ehrlich claimed that the world faced a population timebomb. By the late 1990s, he predicted, american supermarkets would be empty.  So-called cornucopians mock Malthus and Ehrlich for producing some of the most inaccurate forecasts in history. Both failed to take into account improvements in agriculture and the "demographic transition", when population growth rates begin to fall as greater prosperity and female emancipation drive down birth rates.  But as we pass the 7 billion barrier the world enters a dangerous new phase, at risk of what the British government's chief scientific adviser, John Beddington, has called the "perfect storm" of food, water and energy shortages. Now, finally, the Malthusians may be proved right.  What the optimists sometimes ignore is the often precarious role of technology in keeping humanity fed. Since Malthus made his grim predictions, we have had three agricultural revolutions: the advent of technologies in the 18th and 19th centuries such as Jethro Tull's seed drill; the advances resulting from Gregor Mendel's 19th-century insights into inheritance; and finally the "green revolution" of the post-war decades - the development of new strains using systematic artificial selection and husbandry.  The brilliant, Nobel peace prize-winning work of Norman Borlaug and others in creating new varieties of short-stem wheat (less likely to blow over in a storm and rot) and "miracle rice" averted mass famines in asia in the 1960s.  The brutal reality is that, were it not for the green revolution, 2 billion people would be starving today. To feed another 2-3 billion on top of what we have now, we need a doubling in productivity. and this means, say scientists and even a growing number of renegade environmentalists, we are going to have to jettison our squeamishness about genetic manipulation.  at the John Innes Centre for plant research, near Norwich, Brande Wulff and his colleagues have been working on a new strain of wheat that is resistant to what has been called the "polio of agriculture". Stem rust is a nasty fungus that kills wheat and has been responsible for many famines. So feared was it, the Romans prayed to the god Robigus and sacrificed a red-furred animal every year to keep the plague at bay.  One of the triumphs of Borlaug's green revolution was to develop, using conventional hybridisation techniques, a stem-rust-resistant strain of wheat. For 40 years this kept southwest asia and much of africa fed. But in 1999 a new variety of stem rust emerged, in Uganda, to which the new strains have no resistance.  The Ug99 fungus has been sweeping across africa, north through Kenya and Somalia, and in 2005 crossed the Red Sea into Yemen.  "If it reaches the Punjab, which grows 19% of the world's wheat, we face a looming humanitarian crisis. It has been calculated that 200m people could die," explains Wulff.  To date, african farmers have tackled the threat with vast quantities of expensive and environmentally damaging fungicide, but this approach is not sustainable. What is needed is a variety of wheat that is immune to the disease, and here in Norwich they have made one.  It gets better: the wheat I am holding is not only immune to stem rust; it also happens to be highly drought-resistant - and africa is subject to often apocalyptic droughts. Could this be grown in africa? asia? "absolutely," everyone tells me.  The technology takes protective genes isolated in existing wheat varieties, cultivates them in bacteria and then inserts them into the DNa of the target plants. Here, they are also growing transgenic, blightresistant potatoes and nitrogenfixing wheat that would remove the need for costly fertilisers.  NGOs, aid agencies and Third World governments ought to be beating a path to the genetic engineers' doors. But they are not.  The reason is the continuing global resistance to GM technology, a hatred fuelled largely by NGOs such as Greenpeace, Friends of the Earth and GeneWatch UK. So successful have these campaigns been that in recent years both Kenya and Zambia have turned away food aid because it contained GM products.  "The argument of the NGOs is that it is better to let people die of starvation than eat GM," says Professor Giles Oldroyd, an executive at the John Innes Centre. "I think these NGOs are responsible for thousands of deaths."  Mainstream greens detest what they persist in calling "Frankenfoods".  "This is inherently uncertain and risky technology," says Lord Melchett, policy director of the Soil association and veteran anti-GM campaigner. There is no way, he says, he will ever embrace GM. activists claim transgenic crops carry unquantifiable risks, such as the possible transfer of herbicide resistance to the wild plant population, creating an army of "superweeds".  The genetic engineers counter that these fears, while legitimate, have been addressed, and in any case conventional agriculture with its reliance on huge quantities of chemicals is hardly "natural".  In fact, there are signs that the anti-GM movement may be running out of steam. Here at John Innes they are in the second year of a GM field trial of blight-resistant potatoes, and despite substantial media coverage there have been no significant protests; certainly the days of shrieking white-suited activists tearing through experimental crops in the dead of night with scythes and strimmers see