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There’s a continuing gap betweenattitudes towards geneticallymodified (GM) crops in Europeand elsewhere. While the US,Canada, China, India and manyother countries are adopting themwith gusto, most Europeancountries remain at best cautiousand at worst completely hostile totheir introduction.

The reasons for Europe’sapparent Luddism are many andcomplex. In some countries thereis a general abhorrence of anygenetic manipulation. There isalso a distrust of the food industryand official regulators, followingnumerous scares from salmonella,

through Escherichia coli, to bovinespongiform encephalopathy (BSEor mad cow disease). Opponentsargue that, although consumersmay be taking risks by eatinggenetically modified food, all ofthe benefits go into the pockets ofbiotech companies. And there aregenuine differences betweenfarming practices in the US andEurope, where many farms are stillrelatively small and wildlife isdependent on particular farmingtechniques that critics fear will bechanged by the new crops.

Britain’s science academy, theRoyal Society, held an openmeeting last month to try to tackle

these issues and present thescientific assessment of GMcrops. To open, the meetinghighlighted just how much changehad resulted from increasinglyintensive but conventionalagriculture in Europe. Forexample, changes from spring toautumn-sown cereals has had amajor impact on many species,especially birds. Eschewingideological and theoreticalarguments, the meeting focusedon the practical issuessurrounding the potential benefitsand risks of GM crops.

The vehemence of opposition toGM crops is surprising in the viewof Europe’s willingness to embracebiotechnology for medical andother uses. There has, forexample, been little ethicalconcern about the introduction of

News focus

Seeking balance in the GM crop debate

Genetically modified crops are finding economic and environmentalfavour in many countries but in Europe people remain deeplysuspicious about them. A recent meeting in London aimed toencourage scientific debate. Nigel Williams reports.

Fields of contention: trials are still under way in Europe on the potential impact of several genetically modified crops includingoilseed rape, shown above. But in other parts of the world such crops are in full-scale production and appear to be delivering botheconomic and environmental advantages over conventional crop varieties. (Picture: Science Photo Library.)

genetically engineered insulin fortreating diabetes, or a geneticallyengineered version of the enzymechymosin for cheesemaking.Ironically, because chymosin istraditionally extracted from calves’stomachs, the innovation hasmade cheese more acceptable formany vegetarians. “Because thesecheeses contain no GMingredients, and therefore are notusually labeled as GM, few peopleappear to appreciate how muchtheir production depends on GMtechnology,” says Lord May,president of the Royal society.

“The public should be allowed tohear about the potential benefits ofGM crops, as well as the possiblerisks,” says May. “Much of thedebate so far has been skewedtowards the risks and many peoplemay have gained the mistakenimpression that GM offers little orno advantage.” He believes thatthis has been partly because thosewho are ideologically opposed toGM have run a very effectivecampaign, partly because thosewho are developing applications ofGM technology have not perhapsengaged the public as much asthey might have, and partlybecause stories about the risks ofa new technology sell morenewspapers than stories about itsbenefits.

“We are now beginning to hearmore about the potential benefitsof applying GM technology to theproduction of crops. There havebeen recent scientific papersabout the possible benefits towildlife of growing GM sugar beet,and earlier this year researchersreported that GM cotton in Indiacould deliver spectacularincreases in yield and cuts inpesticide use. More work isneeded to explore these and otherpossible benefits,” he argues.“But further research also needsto be carried out into the potentialrisks that may be associated withGM crops. Much of this work willneed to focus on the impact onthe diversity of plant and animallife, and assessed against theproblems associated with theintensification of agriculturalpractices,” he says.

The meeting heard about someresults of studies on GM oil-seedrape now widely grown by

Canadian farmers. Around 85% ofof the crop is now herbicide-resistant GM varieties, said LindaHall, of the University of Alberta.Studies suggest that farmersusing the new varieties benefittedon average by $14.32 per hectare,herbicide use was reduced by6,000 tons and 32 million litres offuel needed for conventional cropspraying were saved.

Concerns about the potentialinvasiveness of GM crop varietieswere also allayed, although non-native species can wreak havoc.Britain has three species fromEastern Asia introduced as gardenplants that present a hugeenvironmental and economicchallenge. Rhododendrons insome parts of western Britainhave invaded and overtakennative ecosystems; Japaneseknotweed and buddleia havethrived in urban, semi-disturbedhabitats causing major structuralproblems. But, says MikeCrawley, of Imperial CollegeLondon, these species do notpresent a good model for lookingat transgenic crops. “Most majorcrop species are annuals and areunable to survive long inuncultivated ground,” he says.“Field trials have shown that it isimportant to study different GMcrops at different sites and underdifferent conditions to determinethe risks and benefits,” he said.

“We are now entering a newphase of the debate, focusing onspecific applications of GMtechnology and weighing up thepotential risks and benefits ineach case. In some instances therisks will be judged to beunacceptable,” says May.

“In other cases, the risksassociated with GM technologywill be judged to be non-existentor negligibly small andoutweighed by the likely benefits,such as with GM vegetariancheeses. As a result, those whoare only interested in portrayingGM technology as eitherinherently dangerous or entirelyproblem-free will be left on themargins, alone with theirideologies and vested interests,whilst everybody else engages ininformed discussion about howwe might use GM technology tocreate the kind of world we want.”

One area remains implacablyopposed to GMOs – organicagriculture. Demand for organicproducts has risen dramatically inrecent years. In France, saleshave increased by 25 per centover recent years as BSE caseshave been confirmed in thatcountry. BSE is widely seen as awatershed. “For the first timepeople realised that merelyattempting to ensure a culinaryend product was safe to eat wasnot a good enough approach. Wehad to look at the entire processby which food is produced,” saysa spokesperson for Britain’s SoilAssociation, which licensesorganic growers. Both Swedenand Austria have more that 10 percent of their agricultural land usedfor organic growing and the figureis rising in most countries.

Any assessment of GM cropsincreasingly needs to take suchconcerns on board. Again, thesituation varies from crop to cropbut it may be possible to segregateGM crops from organic plantingsby sufficient distance to ensureany potential cross-pollination isnegligible — particularly if labellingof GM products is enforced. Suchprospects may present hugechallenges but as Alan Gray, at theCentre for Ecology and Hydrologyin Dorset. pointed out: “We arestarting from scratch with thistechnology and isolation andseparation is a real option.” Themain likely problem comes with thepotential contamination of seed, headded.

But with the now clear potentialfor reductions in pesticide useand less disturbance to arablecrop fields from sprayingherbicide-resistant varieties, themeeting emphasised the need toassess practical risks and benefitsof all aspects of potential GMtechnology for crop species.

“This is a golden age for plantscience,’ says Chris Lamb at theJohn Innes Centre in Norwich.Conventional breeding is‘scramble and sort’ he saidcompared with the potential of‘cut and paste’ with GMtechnology. The prospect ofdeveloping novel crops andfighting the continuing battleagainst plant pests and diseasesis enormous, he said.

Current Biology Vol 13 No 5R164