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ID:39554800
大小:39.50 KB
页数:5页
时间:2019-07-06
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1、WhataresomeoftheadvantagesofGMfoods?Theworldpopulationhastopped6billionpeopleandispredictedtodoubleinthenext50years.Ensuringanadequatefoodsupplyforthisboomingpopulationisgoingtobeamajorchallengeintheyearstocome.GMfoodspromisetomeetthisneedinanumberofways:PestresistanceCroplossesfrominsectpe
2、stscanbestaggering,resultingindevastatingfinanciallossforfarmersandstarvationindevelopingcountries.Farmerstypicallyusemanytonsofchemicalpesticidesannually.Consumersdonotwishtoeatfoodthathasbeentreatedwithpesticidesbecauseofpotentialhealthhazards,andrun-offofagriculturalwastesfromexcessiveus
3、eofpesticidesandfertilizerscanpoisonthewatersupplyandcauseharmtotheenvironment.GrowingGMfoodssuchasB.t.corncanhelpeliminatetheapplicationofchemicalpesticidesandreducethecostofbringingacroptomarket4,5.HerbicidetoleranceForsomecrops,itisnotcost-effectivetoremoveweedsbyphysicalmeanssuchastilli
4、ng,sofarmerswilloftenspraylargequantitiesofdifferentherbicides(weed-killer)todestroyweeds,atime-consumingandexpensiveprocess,thatrequirescaresothattheherbicidedoesn'tharmthecropplantortheenvironment.Cropplantsgenetically-engineeredtoberesistanttooneverypowerfulherbicidecouldhelppreventenvir
5、onmentaldamagebyreducingtheamountofherbicidesneeded.Forexample,MonsantohascreatedastrainofsoybeansgeneticallymodifiedtobenotaffectedbytheirherbicideproductRoundup®6.Afarmergrowsthesesoybeanswhichthenonlyrequireoneapplicationofweed-killerinsteadofmultipleapplications,reducingproductioncostan
6、dlimitingthedangersofagriculturalwasterun-off7.DiseaseresistanceTherearemanyviruses,fungiandbacteriathatcauseplantdiseases.Plantbiologistsareworkingtocreateplantswithgenetically-engineeredresistancetothesediseases8,9.ColdtoleranceUnexpectedfrostcandestroysensitiveseedlings.Anantifreezegenef
7、romcoldwaterfishhasbeenintroducedintoplantssuchastobaccoandpotato.Withthisantifreezegene,theseplantsareabletotoleratecoldtemperaturesthatnormallywouldkillunmodifiedseedlings10.(Note:Ihavenotbeenabletofindanyjournalarticlesorpatentsthatinvolvefishantifree
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