简介：Theobjectivesofthisstudyweretooptimizeinstrumentalparametersandconditionsforanalysisofselectedorganophosphoruspesticides(OPPs)bygaschromatography(GC)withnitrogen-phosphorusdetection(NPD)(GC-NPD);toselectanappropriatesolventsystem;toconductacomparisonofsonicationandshakingextractions;andtoselectanappropriateprocedureforextractingorganophosphoruspesticidesfromsoils.ProcedureⅠconsistedofn-hexaneorpetroleumethertogetherwithacetoneusedassolvents,whileProcedureⅡcontainedseveralsolventsincludingacetone,methanol,dichloromethane,andn-hexaneorpetroleumether.Experimentalresultsindicatedthatamixtureofpetroleumether/acetone(2:1,v/v)couldbeusedinplaceofn-hexane/acetone(2:1,v/v)asitwasalessexpensivesolventsystem.Inaddition,shakingunderawaterbathat20℃wasmoreeffectivethansonication.Also,ProcedureⅠwasmoreeffective,safer,andmoretimesavingthanProcedureⅡ.ProcedureIwasappliedtothreesoiltypesofdifferentorganicmattercontent,withrecoveriesoftheOPPsfromtheyellow-brownsoils,whichhadahigherorganicmattercontent,beinglowerthanthosefromtheyellowandredsoils.

简介：Thenewly-hatchednymphsofthesmallbrownplanthopper(SBPH),Laodelphaxstriatellus,includingfieldandsensitivepopulations,weresubjectedtothehigh-temperature(35°C)treatment.Thenumberofyeast-likeendosymbiotesinSBPHreducedby23.47%-34.23%,57.86%-61.51%and88.96%-90.71%afterthehigh-temperaturetreatmentfor1d,2d,and3d,respectively.However,thesizeofyeast-likeendosymbioteswasnotobviouslyaffected.ResistanceofSBPHtothreeinsecticides(imidacloprid,chlorpyrifosandfipronil)decreasedwiththeincreaseoftreatmenttime.