[史地自然型阅读理解(一)](限时:25分钟)(一)BeesaddanestimatedeighteenbilliondollarsayeartothevalueofAmericancrops
Theypollinate(授粉)flowersthatbecomefruits,nutsandvegetables
But,inrecentyears,honeybeecoloniesintheUnitedStatesandEuropehavebeenshrinking
Scientistshaveproposeddifferenttheoriestoexplainwhatisknownascolonycollapsedisorder
Newresearchsuggeststhatacommonlyusedgroupofinsecticide(杀虫剂)couldcausebeestohaveahardtimefindingtheirwaybacktotheirhive
Thenewresearchlooksattheuseofpesticidescalledneonicotinoids
Theywerefirstusedinthe1990s
Theyarenowputontheseedsofmanymajorcropsaroundtheworld
Theseedlingsabsorbthechemicalsastheygrow
Thatmeansfarmersdonotneedtosprayawholefield
Insteadthereisalittlebitofinsecticideinsideeachplant—includingthepollen(花粉)andthenectar(花蜜)thatthebeeswant
Thereisnotenoughpesticidetoki