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: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:Adistinctivepatternofovipositionlesionsoccursonaginkgoaleanseed,Yimaiacapituliformis,whichlikelywasinflictedbyakalligrammatidlacewingwithalong,sword-like,plant-piercingovipositor.Thisnewlyrecordedovipositiontype,DT272,occursinthe165million-year-oldJiulongshanFormation,ofMiddleJurassicage,inNortheasternChina.DT272consistsfromthreetoseven,approximatelyequallyspacedlesionswithsurroundingcallustissue,thefabricatorofwhichtargetedfleshyouterandinnertissuesofaginkgophytefruit.Thisdistinctivedamagealsoisknownfromthefleshyattachmentpadsurfacesofbasalbennettitaleanbracts.Examinationofthelifehistoryofthisprobableginkgoalean-kalligrammatidovipositioninteractionindicatesthatthespacingoftheeggsinsubstratetissuesdisfavoredinter-larvalcontact,butlittlecartbesaidofdefenseandcounterdefensestrategiesbetweentheplanthostandthenewlyhatchedimrnatures.
简介:Highlydiversifiedcolorationsamongspringtails(Collembola)havebeenwidelyusedforspeciesdiagnosis,buttheirphylogeneticsignificanceispoorlyknown.WeaddressedthisissueinthelargestEntomobryinaegenusEntomobrya,whichpossessesvariablecolorpatternsamongspecies.Therelationshipswithinthegenusandtoothergenerahavealsorarelybeenstudied.BasedonmaterialmainlyfromChina,wehaveconductedamultilocusphylogenyandtopologytestswithlikelihoodandBayesianalgorithms,andaccordinglydemonstratedthenon-monophylyofChineseEntomobrya.Thedivisionoffiveclades,includingEntomobryaandseveralrelatedgenera,coincidedwellwithfivetypesofcolorations,respectively.FurtheranalysesofdivergencetimeandhistoricalbiogeographyrevealedthatChineseEntomobryaoriginatedmainlyfromPalearctic(northernandwestern)ChinainthePaleoceneandEocene.Thisstudyhighlightsthegreatphylo?geneticvaluesaswellastaxonomicusesofcolorationinChineseEntomobrya.MultiplephylogeneticandbiogeographicoriginsofEntomobryaimplyitscomplicatedrelationshipswithbothscaledandunsealedgeneraofEntomobryinae.