简介:本文以中季稻区稻田主要害虫稻飞虱、稻纵卷叶螟和捕食天敌蜘蛛的田间系统调查资料为基础,以害虫—天敌—农药系统为研究对象,应用害虫管理系统工程的原理,处理害虫、捕食天敌与农药三者之间的关系。建立了稻纵叶螟—蜘蛛—甲胺磷和稻飞虱—蜘蛛—甲胺磷两系统优化管理模型,绘制了它们的优化反馈控制策略图,利用微机对系统进行最优监控。使用时输入当前田间害虫与天敌数量,就可对系统作出即时的预测和最优决策。该策略确立的控制害虫的最优性能指标,是使害虫对农作物的为害所造成的损失与防治费用之和最小,并且使害虫和天敌的数量处于系统平衡状态。文中比较分析了该策略与基于经济阈值的常规害虫管理策略,指出了新策略在害虫综合治理中对天敌数量进行控制和管理的作用及其意义。
简介:【背景】米尔顿姬小蜂是一种入侵我国台湾地区的植食性小蜂,能够严重影响水果的产量和食用价值。目前在我国大陆没有分布,由于其个体微小,与近似种区别较小,通过传统的形态学分类方法难以鉴定,因此有必要研究其基因片段序列,探讨分子鉴定方法。【方法】利用PCR方法扩增并测定了米尔顿姬小蜂线粒体16SrRNA和COⅠ基因的部分序列,并对各序列的碱基组成进行了分析。然后根据COⅠ基因部分序列,利用DNAMAN的MaximumLikelihood方法构建了米尔顿姬小蜂与膜翅目其他科的系统发育树。【结果】16SrRNA基因的PCR扩增产物为426bp,COⅠ基因的PCR扩增产物为488bp。通过测序获得米尔顿姬小蜂16SrRNA和COⅠ基因部分序列,序列分析表明,16SrRNA和COⅠ基因的A+T含量均较高,存在较强的A+T偏向性。系统发育树显示,米尔顿姬小蜂与蚜小蜂科的Encarsiaberlesei亲缘关系最近,与姬小蜂科的Chrysocharisnautius、C.eurynota亲缘关系较远。【结论与意义】本研究为米尔顿姬小蜂的分子鉴定提供了依据。
简介:【背景】螺旋粉虱是新入侵海南省的严重为害经济作物及园林苗木的害虫。目前,植物源杀虫剂因具有高效和环境友好等特性而被广泛用于害虫防治中。【方法】采用喷雾法和药膜接触法分别测定了9种植物性杀虫剂对螺旋粉虱的毒力。【结果】在供试的9种植物性杀虫剂中,除虫菊素和鱼藤酮对螺旋粉虱成虫的毒力最强,24h的LC50分别为2.56和34.15mg·L-1;印楝素和苦瓜叶提取物的毒力次之,LC50分别为158.36和311.02mg·L-1。除虫菊素对螺旋粉虱若虫和卵也有一定的触杀作用,LC50分别为61.42和77.39mg·L-1。将印楝素和鱼藤酮分别与除虫菊素以1:1的比例混合,对螺旋粉虱成虫的毒力表现出明显的增效作用,其共毒系数(CTC)分别为193.11和224.35。【结论与意义】除虫菊素、鱼藤酮、印楝素和苦瓜叶提取物对螺旋粉虱均具有较强的毒性;印楝素或鱼藤酮与除虫菊素(1:1)的混合物不仅能增强触杀效果,而且能延缓害虫抗药性的产生。
简介:Highlydiversifiedcolorationsamongspringtails(Collembola)havebeenwidelyusedforspeciesdiagnosis,buttheirphylogeneticsignificanceispoorlyknown.WeaddressedthisissueinthelargestEntomobryinaegenusEntomobrya,whichpossessesvariablecolorpatternsamongspecies.Therelationshipswithinthegenusandtoothergenerahavealsorarelybeenstudied.BasedonmaterialmainlyfromChina,wehaveconductedamultilocusphylogenyandtopologytestswithlikelihoodandBayesianalgorithms,andaccordinglydemonstratedthenon-monophylyofChineseEntomobrya.Thedivisionoffiveclades,includingEntomobryaandseveralrelatedgenera,coincidedwellwithfivetypesofcolorations,respectively.FurtheranalysesofdivergencetimeandhistoricalbiogeographyrevealedthatChineseEntomobryaoriginatedmainlyfromPalearctic(northernandwestern)ChinainthePaleoceneandEocene.Thisstudyhighlightsthegreatphylo?geneticvaluesaswellastaxonomicusesofcolorationinChineseEntomobrya.MultiplephylogeneticandbiogeographicoriginsofEntomobryaimplyitscomplicatedrelationshipswithbothscaledandunsealedgeneraofEntomobryinae.
简介:Investigatinghowcropdomesticationandearlyfarmingmediatedcropattributes,distributions,andinteractionswithantagonistsmayshedlightontoday'sagriculturalpestproblems.Cropdomesticationgenerallyinvolvedartificialselectionfortraitsdesirabletoearlyfarmers,forexample,increasedproductivityoryield,andenhancedqualities,thoughinvariablyitalteredtheinteractionsbetweencropsandinsects,andexpandedthegeographicalrangesofcrops.Thus,somestudiessuggestthatwithcropdomesticationandspread,insectpopulationsonwildcropancestorsgaverisetopestiferousinsectpopulationsoncrops.Here,weaddressedwhethertheemergenceofcornleafhopper(Dalbulusmaidis)asanagriculturalpestmaybeassociatedwithdomesticationandearlyspreadofmaize(Zeamaysmays).WeusedAFLPmarkersandmitochondrialCOIsequencestoassesspopulationgeneticstructuringandhaplotyperelationshipsamongcornleafhoppersamplesfrommaizeanditswildrelativeZeadiploperennisfrommultiplelocationsinMexicoandArgentina.Weuncoveredsevencornleafhopperhaplotypescontainedwithintwohaplogroups,onehaplogroupcontaininghaplotypesassociatedwithmaizeandtheothercontaininghaplotypesassociatedwithZ.diploperennisinamountainoushabitat.Withinthefirsthaplogroup,onehaplotypewaspredominantacrossMexicanlocations,andanotheracrossArgentineanlocations;bothwereconsideredpestiferous.Wesuggestedthatthedivergencetimesofthemaize-associatedhaplogroupandofthe"pestiferous"haplotypesarecorrelatedwiththechronologyofmaizespreadfollowingitsdomestication.Overall,ourresultssupportahypothesispositingthatmaizedomesticationfavoredcornleafhoppergenotypespreadaptedforexploitingmaizesothattheybecamepestiferous,andthatwiththegeographicalexpansionofmaizefarming,cornleafhoppercolonizedZ.diploperennis,ahostexclusivetosecludedhabitatsthatservesasarefugeforarchaiccornleafhoppergenotypicdiversity.B
简介:Interactionsbetweenecologicalcommunitiesofherbivoresandmicrobesarecommonlymediatedbyasharedplant.Atripartiteinteractionbetweenapathogenicfungus-hostplant-herbivorousinsectisanexampleofsuchmutualinfluences.Insuchasystemafungalpathogencommonlyhasanegativeinfluenceonthemorphologyandbiochemistryofthehostplant,withconsequencesforinsectherbivoreperformance.HerewestudiedwhetherthebiotrophicfbngusPodosphaeraferruginea,attackingthegreatburnetSanguisorbaofficinalis,affectscaterpillarperformanceoftheendangeredscarcelargebluebutterflyPhengaristeleius.Ourresultsshowedthatthepathogenicftmgusaffectedthenumberandsizeofinflorescencesproducedbyfood-plantsand,moreimportantly,hadindirect,plant-mediatedeffectsontheabundance,bodymassandimmuneresponseofcaterpillars.Specifically,wefoundtherelationshipbetweencaterpillarabundanceandvariabilityininflorescencesizeonaplanttobepositiveamonghealthyfood-plants,andnegativeamonginfectedfood-plants.Caterpillarsthatfedonhealthyfood-plantsweresmallerthanthosethatfedoninfectedfood-plantsinonestudiedseason,whiletherewasnosuchdifferenceintheotherseason.Weobservedtherelationshipbetweencaterpillarimmuneresponseandtheproportionofinfectedgreatburnetswithinahabitatpatchtobepositivewhencaterpillarsfedonhealthyfood-plants,andnegativewhencaterpillarsfedoninfectedfood-plants.OurresultssuggestthatthisbiotrophicfungalinfectionofthegreatburnetmayimposeasignificantindirectinfluenceonP.teleiuscaterpillarperformancewithpotentialconsequencesforthepopulationdynamicsandstructureofthisendangeredbutterfly.
简介:Humankinddrawsimportantbenefitsfromlarge-scaleecologicalprocessestermedecosystemservices,yetthestatusofseveralofthemisdeclining.Reliablemonitoringmethodsareessentialfortrackingthestatusofecosystemservices.Predationisthemainstayofnaturalpestcontrol,akeyecosystemservice.Weusedgreenplasticinecaterpillarstomonitorpredationpressure,andtoobtainbaselinedataonpredatoractivityintransgenicBtversusnon-BtmaizefieldsinOldandNewWorldcountries.Predationpressurewasmeasuredatgroundandcanopylevelsusinganidentical,small-plotexperimentaldesigninfourEuropeancountries(Denmark,Slovakia,RomaniaandItaly)andArgentina.Totalpredationrateinmaizewasll.7%d^-1(min.7.2%d^-1inArgentina,max.29.0%d^-1inRomania).Artificialcaterpillarswereattackedbothbyinvertebrates(mostlychewinginsectswith42.0%oftheattackmarks,andantswith7.1%,butalsopredatoryandparasitoidwasps,spidersandslugs),andvertebrates(smallmammals25.5%,andbirds20.2%).Totalpredationatgroundlevel(15.7%d^-1)wassignificantlyhigherthaninmaizecanopies(6.0%d^-1)inallcountries,exceptArgentina.WefoundnosignificantdifferencesbetweenpredatorpressureinBtversusnon-Btmaizeplots.Theartificialcaterpillarmethodprovidedcomparable,quantitativedataonpredationintensity,andprovedtobesuitableformonitoringnaturalpestcontrol.Thismethodusefullyexpandstheexistingtoolkitbydirectlymeasuringecologicalfunctionratherthanstructure.
简介:Thebrownstinkbug(BSB),Euschistusservus(Say)(Hemiptera:Pentatomidae),isaseriouseconomicpestofcornproductioninthesoutheasternUnitedStates.TheBSBpopulationdynamicswasmonitoredfor17weeksfromtasselingtopreharvestofcornplants(i.e.,lateMaytomid-September)usingpheromonetrapsinthreecornfieldsfrom2005to2009.ThetrapdatashowedtwopeaksinearlyJuneandmid-August,respectively.Therelationshipbetweentrapcatchandpregrowingseasonweatherdatawasexaminedusingcorrelationandstepwisemultiplefactorregressionanalyses.Weatherindicesusedfortheanalyseswereaccumulatedgrowingdegreeday(AGDD),numberofdayswithminimumtemperaturebelow0℃(Subz),accumulateddailymaximum(AMaxT)andminimumtemperatures(AMinT)andrainfall(ARain).Theweatherindiceswerecalculatedwithlower(10℃)andupper(35℃)asbiologicalthresholds.Theparametersusedinregressionanalysiswereseasonalabundance(oroverallmeanofBSBadultcatch)(BSBm),numberofBSBadultscaughtatapeak(PeakBSB),andpeakweek(Peakwk).TheBSBmwasnegativelyrelatedtohightemperature(AmaxTorAGDD)consistently,whereasIstPeakBSBwaspositivelycorrelatedtobothARainandSubz,irrespectiveofweatherdatadurations(thefirst4,4.5,and5months).Incontrast,the7-monthweatherdata(AGDD7)werenegativelycorrelatedtotheBSBmonly,butnotcorrelatedtothesecondPeakBSB.The5-yearmonitoringstudydemonstratedthatweatherdatacanbeusedtopredicttheBSBabundanceatitsfirstpeakintasselingcornfieldsinthesoutheasternU.S.states.
简介:Thewheatmidge,Sitodiplosismosellana,isaseriouspestofwheatworldwide.InNorthAmerica,managementofS.mosellanainspringwheatreliesonthetimelyapplicationofpesticides,basedonmidgeadultslevelscaughtinpheromonetrapsorseenviafieldscoutingduringwheatheading.Inthiscontext,biopesticidescanbeaneffectivealternativetopesticidesforcontrollingS.mosellanawithinanIntegratedPestManagementprogram.AfieldstudyusinginsectpathogenicfungusBeauveriabassianaGHA,nematodeSteinernemaJeltiaewithBarricadepolymergel1%,pyrethrin,combinedformulationsofB.bassianaGHAandpyrethrin,Jasmonicacid(JA)andchlorpyrifos(chemicalcheck)wasperformedtodeterminetowhichextenttheyaffectmidgelarvalpopulations,kerneldamagelevels,grainyield,andquality,andtheimpactsonadultparasitoidMacroglenespenetranspopulations.TheresultsindicatedthatbiopesticidesJAandS.Jeltiaewerethemosteffectiveinreducinglarvalpopulationsandkerneldamagelevels,andproducedahigherspringwheatyieldwhencomparedtothewatercontrolatbothstudylocations(EastValierandNorthValier,Montana,USA).IncreasedtestweightinwheathadbeenrecordedwithtwopreviousbiopesticidesatEastValierbutnotforNorthValier,whencomparedoverwatercontrol.Theseresultswerecomparableinefficacytothechlorpyrifos.ThisstudyalsosuggestedthatB.bassianaandpyrethrinmayworksynergistically,asexemplifiedbylowertotallarvalpopulationsandkerneldamagelevelswhenappliedtogether.ThisstudydidnotdemonstratetheeffectofanytreatmentsonM.penetranspopulations.
简介:Thepealeafminer(Liriomyzahuidobrensis)isanotoriouspestofvegetablesandornamentalplantsworldwide.Despitealargenumberofstudiesonitsbiologyandecology,thecourtshipbehaviorandsexualcommunicationofthisspeciesremainunclear.Here,westudiedvibrationalcommunicationinthesexualinteractionofthepealeafminer.Onhostplantleaves,femalesandmalesbehaviorallydisplayedthebobbing-quiveringalternation,whichfinallyledtocopulation.Moreover,recordsoflaservibrometryrevealedthreesignalduetsunderlyingthebehavioralalternation.Sexuallymaturemalesspontaneouslyemittedcalls(MCs)toinitiatetheduets.ThefemalesrapidlyrespondedtoMCsbyemittingreplies(FRs)thatarelongerinduration.TheFRsfurthertriggeredmalereplies(MRs)intheirsearchforpotentialpartners.Leafminer-producedvibrationalsignalsconveyefficientinformationtopartnersandgeneratepairformationonstretchedsubstrates,suchasplantleavesandnylonmesh,butcannotelicitresponsesondensesubstrates,suchasglassandplastic.VibrationalplaybacksofbothMCsandFRscanelicitrepliesinfemalesandmales,respectively.Thisstudycompletelycharacterizessubstrate-bornevibrationalduetsinadipteraninsect.Thediscoveryofvibrationalsexsignalsinthepealeafminerprovidesnewinsightsforthedevelopmentofnovelapproachestocontrolthepestanditsrelativespecies.
简介:Honeybees(Apismellifera)havehaplodiploidsexdetermination:malesdevelopfromunfertilizedeggsandfemalesdevelopfromfertilizedones.Thedifferencesinlarvalfoodalsodeterminethedevelopmentoffemales.Herewecomparedthetotalsomaticgeneexpressionprofilesof2-dayand4-day-olddrone,queenandworkerlarvaebyRNASeq.Theresultsfromaco-expressionnetworkanalysisonallexpressedgenesshowedthat2-day-olddroneandworkerlarvaewerecloseringeneexpressionprofilesthan2-day-oldqueenlarvae.Thisindicatedthatforyounglarvae(2-day-old)environmentalfactorssuchaslarvaldiethaveagreatereffectongeneexpressionprofilesthanploidyorsexdetermination.Droneshadthemostdistinctgeneexpressionprofilesatthe4-daylarvalstage,suggestingthathaploidy,orsexdramaticallyaffectsthegeneexpressionofhoneybeelarvae.Dronelarvaeshowedfewerdifferencesingeneexpressionprofilesatthe2-dayand4-daytimepointsthantheworkerandqueenlarvalcomparisons(598against1190and1181),suggestingadifferentpatternofgeneexpressionregulationduringthelarvaldevelopmentofhaploidmalescomparedtodiploidfemales.Thisstudyindicatesthatearlyindevelopmentthequeencastehasthemostdistinctgeneexpressionprofile,perhapsreflectingtheveryrapidgrowthandmorphologicalspecializationofthiscastecomparedtoworkersanddrones.Laterindevelopmentthehaploidmaledroneshavethemostdistinctgeneexpressionprofile,perhapsreflectingtheinfluenceofploidyorsexdeterminationongeneexpression.
简介:MultitoxinBt-cropsexpressinginsecticidaltoxinswithdifferentmodesofaction,forexample,CryandVip,areexpectedtoimproveresistancemanagementintargetpests.WhileCry1Aresistancehasbeenrelativelywellcharacterizedinsomeinsectspecies,thisisnotthecaseforVip3A,forwhichnomechanismofresistancehasyetbeenidentified.HereweappliedHT-SuperSAGEtoanalyzethetranscriptomeoftheguttissueoftobaccobudwormHeliothisvirescens(F.)laboratory-selectedforVip3Aaresistance.Fromatotalof1324252sequencereads,5895126-bptagswereobtainedrepresenting17751nonsingletonuniquetranscripts(UniTags)fromgeneticallysimilarVip3Aa-resistant(Vip-Sel)andsusceptiblecontrol(Vip-Unsel)strains.Differentialexpressionwassignificant(≥2.5foldor≤0.4;P<0.05)for1989sequences(11.2%oftotalUniTags),where420representedoverexpressed(OE)and1569underexpressed(UE)genesinVip-Sel.BLASTNsearchesmapped419UniTagstoH.virescenssequencecontigs,ofwhich,416(106OEand310UE)wereunambiguouslyannotatedtoproteinsinNCBInonredundantproteindatabases.GeneOntologydistributed345ofannotatedUniTagsin14functionalcategorieswithmetabolism(includingserine-typehydrolases)andtranslation/ribosomebiogenesisbeingthemostprevalent.AUniTaghomologoustoaparticularmemberoftheREsponsetoPAThogen(REPAT)familywasfoundamongmostoverexpressed,whileUniTagsrelatedtotheputativeVip3Aa-bindingribosomalproteinS2(RpS2)wereunderexpressed.qRT-PCRofasubsetofUniTagsvalidatedtheHT-SuperSAGEdata.ThisstudyisthefirstprovidinglepidopteranguttranscriptomeassociatedwithVip3Aaresistanceandafoundationforfutureattemptstoelucidatetheresistancemechanism.
简介:Diversityandcompositionoflepidopteranmicrobiotasarepoorlyinvestigated,especiallyacrossthedifferentdevelopmentalstages.Toimprovethisknowledge,wecharacterizethemicrobiotaamongdifferentdevelopmentalstagesoftheIndianmealmoth,Plodiainterpunctella,whichisconsideredoneofthemajorpestofcommoditiesworld-wide.Usingculture-independentapproachbasedonIllumina16SrRNAgenesequencingwecharacterizedthemicrobiotaoffourdevelopmentalstages:eggs,first-,andlast-instarlarvae,andadult.Atotalof1022bacterialOTUswereobtained,showingaquitediversifiedmicrobiotaassociatedtoalltheanalyzedstages.ThemicrobiotasassociatedwithP.interpunctellaresultedalmostconstantthroughoutthedevelopmentalstages,withapproximately77%ofbacterialOTUsbelongingtothephylumofProteobacteria.ThedominantbacterialgenusisrepresentedbyBurkholderia(?64%),followedbyPropionibacterium,Delftia,Pseudomonas,andStenotrophomonas.Acorebacterialcommunity,composedof139OTUs,wasdetectedinallthedevelopmentalstages,amongwhich112OTUswereassignedtothegenusBurkholderia.Aphylogeneticreconstruction,basedonthe16SrRNA,revealedthatourBurkholderiaOTUsclusteredwithBurkholderiacepaciacomplex,inthesamegroupofthoseisolatedfromthehemipteransGossypariaspuriaandAcanthococcusaceris.Thefunctionalprofiling,predictedonthebaseofthebacterial16SrRNA,indicatesdifferencesinthemetabolicpathwaysrelatedtometabolismofaminoacidsbetweenpreimaginalandadultstages.Wecanhypothesizethatbacteriamaysupporttheinsecthostduringpreimaginalstages.
简介:InsectshavealargefamilyofC-typelectinsinvolvedincelladhesion,pathogenrecognitionandactivationofimmuneresponses.Inthisstudy,32transcriptsencodingC-typelectindomainproteins(CTLDPs)wereidentifiedfromtheThitarodesxiaojinensistranscriptome.Accordingtotheirdomainstructures,sixCTLDPswithonecarbohydraterecognitiondomain(CRD)wereclassifiedintotheCTL-Ssubfamily.Theother23CTLDPswithtwoCRDsweregroupedintotheimmulectin(IML)subfamily.TheremainingthreewithextraregulatorydomainsweresortedintotheCTL-Xsubfamily.PhylogeneticanalysisshowedthatCTL-SandCTL-Xmembersfromdifferentinsectscouldformorthologousgroups.Incontrast,noT.xiaojinensisIMLorthologueswerefoundinotherinsects.Remarkablelineage-specificexpansioninthissubfamilywasobservedreflectingthattheseCTLDPs,asimportantreceptors,haveevolveddiversifiedmembersinresponsetoavarietyofmicrobes.PredictionofbindingligandsrevealedthatT.xiaojinensis,acoldadaptedspecies,conservedtheabilityofCRDstocombinewithCa^2+tokeepitsreceptorsfromfreezing.ComparativeanalysisofinductionofCTLDPgenesafterdifferentimmunechallengesindicatedthatIMLsmightplaycriticalrolesinimmunedefenses.ThisstudyexaminedT.xiaojinensisCTLDPsandprovidesabasisforfurtherstudiesoftheircharacteristics.
简介:Ininsects,thegustatorysystemplaysacrucialroleinmultiplephysiologicalbehaviors,includingfeeding,toxinavoidance,courtship,matingandoviposition.Gustatorystimulifromtheenvironmentarerecognizedbygustatoryreceptors.Todate,littleisknownaboutthefunctionofgustatoryreceptorsinagriculturalpestinsects.Inthisstudy,weclonedasugargustatoryreceptorgene,N/Gr11,fromthebrownplanthopper(BPH),Nilaparvatalugens(Stal),aseriouspestofriceinAsia;wethenidentifieditsligands,namely,fructose,galactoseandarabinose,bycalciumimagingassay.AfterinjectionofN/Gr11doublestrandedRNA,wefoundthatthenumberofeggslaidbyBPHdecreased.Moreover,wefoundthatN/Gr11inhibitedthephosphorylationofadenosinemonophosphate-activatedproteinkinase(AMPK)andpromotedthephosphorylationofproteinkinaseB(AKT).ThesefindingsdemonstratedthatN/Gr11couldacceleratethefecundityofBPHthroughAMPK-andAKT-mediatedsignalingpathways.Thisisthefirstreporttoindicatethatagustatoryreceptormodulatesthefecundityofinsectsandthatthereceptorcouldbeapotentialtargetforpestcontrol.
简介:Theinsectmidgutepitheliumiscomposedofcolumnar,goblet,andregenerativecells.Columnarepithelialcellsarethemostabundantandhavemembraneprotrusionsthatformthebrushbordermembrane(BBM)ontheirapicalside.Theseincreasesurfaceareaavailableforthetransportofnutrients,butalsoprovideopportunitiesforinteractionwithxenobioticssuchaspathogens,toxinsandhostplantallelochemicals.RecentimprovementsinproteomicandbioinfbrmaticstoolsprovidedanopportunitytodeterminetheproteomeoftheT.niBBMinunprecedenteddetail.ThisstudyreportstheidentificationofproteinsfromBBMvesicles(BBMVs)usingsingledimensionpolyacrylamidegelelec?trophoresiscoupledwithmulti-dimensionalproteinidentificationtechnology.Morethan3000proteinswereassociatedwiththeBBMVofwhich697werepredictedtopossesseitherasignalpeptide,atleastonetransmembranedomainoraGPI-anchorsignal.Ofthese,bioinfbrmaticsanalysisandmanualcurationpredictedthat185maybeassociatedwiththeBBMVorepithelialcellplasmamembrane.Thesearediscussedwithrespecttotheirpredictedfunctions,namelydigestion,nutrientuptake,cellsignaling,development,cell-cellinteractions,andotherfunctions.Webelievethistobethemostdetailedproteomicanalysisofthelepidopteranmidgutepitheliummembranetodate,whichwillprovideinformationtobetterunderstandthebiochemical,physiologicalandpathologicalprocessestakingplaceinthelarvalmidgut.