新sat官方指南阅读第十五篇全解析

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1、官网网站：imzsat.genshuixue.com________________________________________________________________新SAT官方指南阅读第十五篇全解析ThispassageisadaptedfromRichardJ.SharpeandLisaHeyden,“HoneyBeeColonyCollapseDisorderisPossiblyCausedbyaDietaryPyrethrumDeficiency.”©2009byElsevie

2、rLtd.Colonycollapsedisorderischaracterizedbythedisappearanceofadultworkerbeesfromhives.HoneybeesarehoststothepathogeniclargeectoparasiticmiteVarroadestructor(Varroamites).Thesemitesfeedonbeehemolymph(blood)andcankillbeesdirectlyorbyincreasingtheirsusce

3、ptibilitytosecondaryinfectionwithfungi,bacteriaorviruses.Littleisknownaboutthenaturaldefensesthatkeepthemiteinfectionsundercontrol.5PyrethrumsareagroupoffloweringplantswhichincludeChrysanthemumcoccineum,Chrysanthemumcinerariifolium,Chrysanthemummarscha

4、lli,andrelatedspecies.Theseplantsproducepotentinsecticideswithanti-miteactivity.Thenaturallyoccurringinsecticidesareknownaspyrethrums.Asynonymforthenaturallyoccurringpyrethrumsispyrethrinandsyntheticanaloguesofpyrethrumsareknownaspyrethroids.Infact,the

5、humanmiteinfestationknownas10scabies(Sarcoptesscabiei)istreatedwithatopicalpyrethrumcream.Wesuspectthatthebeesofcommercialbeecolonieswhicharefedmono-cropsarenutritionallydeficient.Inparticular,wepostulatethattheproblemisadietdeficientinanti-mitetoxins:

6、pyrethrums,andpossiblyothernutrientswhichareinherentinsuchplants.Without,atleast,intermittentfeedingonthepyrethrumproducingplants,beecoloniesaresusceptibletomite15infestationswhichcanbecomefataleitherdirectlyorduetoasecondaryinfectionof1官网网站：imzsat.gen

7、shuixue.com________________________________________________________________immunocompromisedornutritionallydeficientbeesThissecondaryinfectioncanbeviral,bacterialorfungalandmaybeduetooneormorepathogens.Inaddition,immunocompromisedornutritionallydeficie

8、ntbeesmaybefurtherweakenedwhencommerciallyproducedinsecticidesareintroducedintotheirhivesbybeekeepersinanefforttofightmiteinfestation.Wefurther20postulatethattheproperdosagenecessarytopreventmiteinfestationmaybebetterlefttothebees,whoma