简介：Basedonthestrongchelatingpropertyofbathophenanthrolinedisulfonicacid(BPDS)withFe(Ⅱ),rootFe(Ⅲ)chelatereductaseactivityisusuallymeasuredwithaspectrophotometerusingMES(2-morpholinoethanesulfonicacid)orHEPES(2-(4-(2-Hydroxyethyl)-1-piperazinyl)ethanesulfonicacid)bufferinthedarkbecauseofhighautoreductionrateofFe(Ⅲ)inthepresenceoflight.However,theexclusionoflightisinconvenient,especiallywhenanalyzingalargenumberofsamples.TheobjectiveofthisstudywastodevelopanewmethodfordeterminationofrootreductaseactivityundernormallaboratoryconditionsusingasuitablebuffercompositionandFe(Ⅲ)concentrationtoeliminatetheautoreductionofFe(Ⅲ).AmodifiedmethodusingaTris(2-amino-2-hydroxymethyl-1,3-propanediol)bufferatpH7.5insteadofMESorHEPESbufferandadecreasedFeEDTA(Feethylenediaminetetraaceticacid)concentrationof50μmolL-1wasdeveloped.TheautoreductionofFe(Ⅲ)usingtheTrisbufferwasundetectablefortemperaturesat4and28℃andwasalsomuchlowerthanthatusingtheotherbuffersevenwithsunlightduringmeasurementofFe(Ⅲ)reduction.Furthermore,thedifferencesinFe(Ⅲ)reductaseactivityamong5plantspeciesand14redclovercultivars(TrifoliumpratenseL.)couldbeeasilydetectedwiththemodifiedmethod.ThemethoddevelopedinthisstudytomeasurerootFechelatereductaseactivitywasnotonlyeffectiveandreliablebutalsoeasilymanagedundernormallaboratorylightconditions.

简介：Microbecommunitiesinrhizosphereecosystemsareimportantforplanthealthbutthereislimitedknowledgeofthemintherhizospheresofgeneticallymodified(GM)plants,especialfortreespecies.WeusedtheamplitudesequencingmethodtoanalyzetheV4regionsofthe16SrRNAgenetoidentifychangesinbacterialdiversityandcommunitystructureintwoGMlines(D520andD521),onenon-geneticallymodified(nonGM)lineandinuncultivatedsoil.Afterchimerafiltering,468.133sequencesinthedomainBacteriaremained.Thereweretendominanttaxonomicgroups(with[1%ofallsequences)acrossthesamples.241of551genera(representingaratioof97.33%)werecommontoallsamples.AVenndiagramshowedthat1.926operationaltaxonomicunits(OTUs)weresharedbyallsamples.Wefoundaspecificchange,areductioninChloroflexi,inthemicroorganismsintherhizospheresoilplantedwithpoplars.Takentogether,theresultsshowedfewstatisticaldifferencesinthebacterialdiversityandcommunitystructurebetweentheGMlineandnon-GMline,thissuggeststhattherewasnoorverylimitedimpactofthisgeneticmodificationonthebacterialcommunitiesintherhizosphere.

简介：Thetransgenicrice,Zhongda2,whichwasgeneticallymodifiedfromanindicaricelineZhuxianBbyricechitinasegene(RC24),hadhighresistancetoricesheathblight(Rhizoctoniasolam)inlaboratoryandatwo-yearfieldexperiment.ThepathogencouldinvadesheathofZhongda2andinducesymptomsofthedisease.NodifferencewasnotedintimeofpenetrationorincubationperiodbetweenZhongda2andnon-transgenicricecontrol,ZhuxianB,butthehyphaelysatecouldbeobservedeadierthancontrol.Itsresistanceexpressedastoinhibitthegrowthofmyceliuminhosttissue.F1sfromZhongda2(♂)crossedwithotherfivenon-transgenicricelinesshowedhigherresistancethandonornon-transgenicparents,buttheresistancewasdifferentalongwiththedifferentmaternalparents.