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1、洛基英语，中国在线英语教育领导品牌Ifyouwanttosparkaheateddebateatadinnerparty,bringupthetopicaboutgeneticallymodifiedfoods.Formanypeople,theconceptofgeneticallyaltered,high-techcropproductionraisesallkindsofenvironmental,health,safetyandethicalquestions.Particularlyincou
2、ntrieswithlongagrariantraditions--andvocalgreenlobbies--theideaseemsagainstnature.Infact,geneticallymodifiedfoodsarealreadyyewmuchapartofourlives.AthirdofthecornandmorethanhalfthesoybeansandcottongrownintheUSlastyearweretheproductofbiotechnology,accordin
3、gtotheDepartmentofAgriculture.Morethan65millionacresofgeneticallymodifiedcropswillbeplantedintheUSthisyear.Thegeneticisoutofthebottle.Yetthereareclearlysomeveryrealissuesthat,needtoberesolved,lakeanynewproductenteringthefoodchain,geneticallymodifiedfoods
4、mustbesubjectedtorigoroustesting.Inwealthycount,des,thedebateaboutbiotechistemperedbythefactthatwehavearicharrayoffoodstochoosefrom--andasupplythatfarexceedsourneeds.Indevelopingcountriesdesperatetofeedfast-growingandunderfedpopulations。theissueissimpler
5、andmuchmoreurgent:Dothebenefitsofbiotechoutweightherisks?Thestatisticsonpopulationgrowthandhungeraredisturbing.Lastyeartheworld'spopulationreached6billion.Andby2050,theUNestimates,itwillbeprobablynear9billion.Almostallthatgrowthwilloccurindevelopingcount
6、ries.Atthesametime,theworld'savailablecultivablelandperpersonisdeclining.Arablelandhasdeclinedsteadilysince1960andwilldecreasebyhalfoverthenext50years,accordingtotheInternationalServicefortheAcquisitionofAgri-BiotechApplications(ISAAA).Howcanbiotechhelp?
7、Biotechnologistshavedevelopedgeneticallymodifiedricethatisfortifiedwithbeta-carotene(β-胡萝卜素)—whichthebodyconvertsintovitaminA--andadditionaliron,midtheyareworkingonotherkindsofnutritionallyimprovedcrops.Biotechcanalsoimprovefarmingproductivityinplaceswhe
8、refoodshortagesarecausedbycropdamageattributiontopests,drought,poorsoilandcropviruses,bacteriaorfungi(真菌).Damagecausedbypestsisincredible.TheEuropeancornborer,forexample,destroys40milliontonsoftheworld'scorncropsannual]y,a
